Bump version to 3.6.2

This reverts commit 2d58118d7c.

.gitignore

@@ -28,6 +28,7 @@
 /WindowsInstaller/Install Files/qortal.jar
 /*.7z
 /tmp
+/wallets
 /data*
 /src/test/resources/arbitrary/*/.qortal/cache
 apikey.txt

WindowsInstaller/Qortal.aip

@@ -17,10 +17,10 @@
     <ROW Property="Manufacturer" Value="Qortal"/>
     <ROW Property="MsiLogging" MultiBuildValue="DefaultBuild:vp"/>
     <ROW Property="NTP_GOOD" Value="false"/>
-    <ROW Property="ProductCode" Value="1033:{DEA09B3D-AFFA-409F-B208-E148E9A9005D} 1049:{79180B3D-8A6B-4DED-BD60-1A58F941E1DE} 2052:{90F65B96-22CD-41FA-82B0-E65183EA1EF9} 2057:{AB4872AC-E794-42BD-9305-8DFD06243A88} " Type="16"/>
+    <ROW Property="ProductCode" Value="1033:{E5597539-098E-4BA6-99DF-4D22018BC0D3} 1049:{2B5E55A2-142A-4BED-B3B9-5657162282B7} 2052:{6F19171F-4743-4127-B191-AAFA3FA885D2} 2057:{A1B3108D-EC5D-47A1-AEE4-DBD956E682FB} " Type="16"/>
     <ROW Property="ProductLanguage" Value="2057"/>
     <ROW Property="ProductName" Value="Qortal"/>
-    <ROW Property="ProductVersion" Value="3.2.3" Type="32"/>
+    <ROW Property="ProductVersion" Value="3.4.3" Type="32"/>
     <ROW Property="RECONFIG_NTP" Value="true"/>
     <ROW Property="REMOVE_BLOCKCHAIN" Value="YES" Type="4"/>
     <ROW Property="REPAIR_BLOCKCHAIN" Value="YES" Type="4"/>
@@ -212,7 +212,7 @@
     <ROW Component="ADDITIONAL_LICENSE_INFO_71" ComponentId="{12A3ADBE-BB7A-496C-8869-410681E6232F}" Directory_="jdk.zipfs_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_71" Type="0"/>
     <ROW Component="ADDITIONAL_LICENSE_INFO_8" ComponentId="{D53AD95E-CF96-4999-80FC-5812277A7456}" Directory_="java.naming_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_8" Type="0"/>
     <ROW Component="ADDITIONAL_LICENSE_INFO_9" ComponentId="{6B7EA9B0-5D17-47A8-B78C-FACE86D15E01}" Directory_="java.net.http_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_9" Type="0"/>
-    <ROW Component="AI_CustomARPName" ComponentId="{63FD92A7-4AE2-46A0-9B83-EB27DA636C65}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
+    <ROW Component="AI_CustomARPName" ComponentId="{F17029E8-CCC4-456D-B4AC-1854C81C46B6}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
     <ROW Component="AI_ExePath" ComponentId="{3644948D-AE0B-41BB-9FAF-A79E70490A08}" Directory_="APPDIR" Attributes="260" KeyPath="AI_ExePath"/>
     <ROW Component="APPDIR" ComponentId="{680DFDDE-3FB4-47A5-8FF5-934F576C6F91}" Directory_="APPDIR" Attributes="0"/>
     <ROW Component="AccessBridgeCallbacks.h" ComponentId="{288055D1-1062-47A3-AA44-5601B4E38AED}" Directory_="bridge_Dir" Attributes="0" KeyPath="AccessBridgeCallbacks.h" Type="0"/>

pom.xml

@@ -3,13 +3,13 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.qortal</groupId>
 	<artifactId>qortal</artifactId>
-	<version>3.2.3</version>
+	<version>3.6.2</version>
 	<packaging>jar</packaging>
 	<properties>
 		<skipTests>true</skipTests>
-		<altcoinj.version>6628cfd</altcoinj.version>
+		<altcoinj.version>7dc8c6f</altcoinj.version>
 		<bitcoinj.version>0.15.10</bitcoinj.version>
-		<bouncycastle.version>1.64</bouncycastle.version>
+		<bouncycastle.version>1.69</bouncycastle.version>
 		<build.timestamp>${maven.build.timestamp}</build.timestamp>
 		<ciyam-at.version>1.3.8</ciyam-at.version>
 		<commons-net.version>3.6</commons-net.version>
@@ -34,6 +34,8 @@
 		<package-info-maven-plugin.version>1.1.0</package-info-maven-plugin.version>
 		<jsoup.version>1.13.1</jsoup.version>
 		<java-diff-utils.version>4.10</java-diff-utils.version>
+		<grpc.version>1.45.1</grpc.version>
+		<protobuf.version>3.19.4</protobuf.version>
 	</properties>
 	<build>
 		<sourceDirectory>src/main/java</sourceDirectory>
@@ -705,5 +707,25 @@
 			<artifactId>java-diff-utils</artifactId>
 			<version>${java-diff-utils.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>io.grpc</groupId>
+			<artifactId>grpc-netty</artifactId>
+			<version>${grpc.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>io.grpc</groupId>
+			<artifactId>grpc-protobuf</artifactId>
+			<version>${grpc.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>io.grpc</groupId>
+			<artifactId>grpc-stub</artifactId>
+			<version>${grpc.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>com.google.protobuf</groupId>
+			<artifactId>protobuf-java</artifactId>
+			<version>${protobuf.version}</version>
+		</dependency>
 	</dependencies>
 </project>

src/main/java/com/rust/litewalletjni/LiteWalletJni.java

@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * LiteWalletJni code based on https://github.com/PirateNetwork/cordova-plugin-litewallet
+ *
+ * MIT License
+ *
+ * Copyright (c) 2020 Zero Currency Coin
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.rust.litewalletjni;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.controller.PirateChainWalletController;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+public class LiteWalletJni {
+
+    protected static final Logger LOGGER = LogManager.getLogger(LiteWalletJni.class);
+
+    public static native String initlogging();
+    public static native String initnew(final String serveruri, final String params, final String saplingOutputb64, final String saplingSpendb64);
+    public static native String initfromseed(final String serveruri, final String params, final String seed, final String birthday, final String saplingOutputb64, final String saplingSpendb64);
+    public static native String initfromb64(final String serveruri, final String params, final String datab64, final String saplingOutputb64, final String saplingSpendb64);
+    public static native String save();
+
+    public static native String execute(final String cmd, final String args);
+    public static native String getseedphrase();
+    public static native String getseedphrasefromentropyb64(final String entropy64);
+    public static native String checkseedphrase(final String input);
+
+
+    private static boolean loaded = false;
+
+    public static void loadLibrary() {
+        if (loaded) {
+            return;
+        }
+        String osName = System.getProperty("os.name");
+        String osArchitecture = System.getProperty("os.arch");
+
+        LOGGER.info("OS Name: {}", osName);
+        LOGGER.info("OS Architecture: {}", osArchitecture);
+
+        try {
+            String libFileName = PirateChainWalletController.getRustLibFilename();
+            if (libFileName == null) {
+                LOGGER.info("Library not found for OS: {}, arch: {}", osName, osArchitecture);
+                return;
+            }
+
+            Path libPath = Paths.get(PirateChainWalletController.getRustLibOuterDirectory().toString(), libFileName);
+            System.load(libPath.toAbsolutePath().toString());
+            loaded = true;
+        }
+        catch (UnsatisfiedLinkError e) {
+            LOGGER.info("Unable to load library");
+        }
+    }
+
+    public static boolean isLoaded() {
+        return loaded;
+    }
+
+}

src/main/java/org/qortal/ApplyUpdate.java

@@ -8,6 +8,7 @@ import java.nio.file.Paths;
 import java.nio.file.StandardCopyOption;
 import java.security.Security;
 import java.util.*;
+import java.util.stream.Collectors;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -18,6 +19,8 @@ import org.qortal.api.ApiRequest;
 import org.qortal.controller.AutoUpdate;
 import org.qortal.settings.Settings;
 
+import static org.qortal.controller.AutoUpdate.AGENTLIB_JVM_HOLDER_ARG;
+
 public class ApplyUpdate {
 
 	static {
@@ -37,7 +40,7 @@ public class ApplyUpdate {
 	private static final String JAVA_TOOL_OPTIONS_NAME = "JAVA_TOOL_OPTIONS";
 	private static final String JAVA_TOOL_OPTIONS_VALUE = "-XX:MaxRAMFraction=4";
 
-	private static final long CHECK_INTERVAL = 10 * 1000L; // ms
+	private static final long CHECK_INTERVAL = 30 * 1000L; // ms
 	private static final int MAX_ATTEMPTS = 12;
 
 	public static void main(String[] args) {
@@ -197,6 +200,11 @@ public class ApplyUpdate {
 			// JVM arguments
 			javaCmd.addAll(ManagementFactory.getRuntimeMXBean().getInputArguments());
 
+			// Reapply any retained, but disabled, -agentlib JVM arg
+			javaCmd = javaCmd.stream()
+					.map(arg -> arg.replace(AGENTLIB_JVM_HOLDER_ARG, "-agentlib"))
+					.collect(Collectors.toList());
+
 			// Call mainClass in JAR
 			javaCmd.addAll(Arrays.asList("-jar", JAR_FILENAME));
 
@@ -205,7 +213,7 @@ public class ApplyUpdate {
 		}
 
 		try {
-			LOGGER.info(() -> String.format("Restarting node with: %s", String.join(" ", javaCmd)));
+			LOGGER.info(String.format("Restarting node with: %s", String.join(" ", javaCmd)));
 
 			ProcessBuilder processBuilder = new ProcessBuilder(javaCmd);
 
@@ -214,8 +222,15 @@ public class ApplyUpdate {
 				processBuilder.environment().put(JAVA_TOOL_OPTIONS_NAME, JAVA_TOOL_OPTIONS_VALUE);
 			}
 
-			processBuilder.start();
-		} catch (IOException e) {
+			// New process will inherit our stdout and stderr
+			processBuilder.redirectOutput(ProcessBuilder.Redirect.INHERIT);
+			processBuilder.redirectError(ProcessBuilder.Redirect.INHERIT);
+
+			Process process = processBuilder.start();
+
+			// Nothing to pipe to new process, so close output stream (process's stdin)
+			process.getOutputStream().close();
+		} catch (Exception e) {
 			LOGGER.error(String.format("Failed to restart node (BAD): %s", e.getMessage()));
 		}
 	}

src/main/java/org/qortal/account/Account.java

@@ -8,11 +8,13 @@ import javax.xml.bind.annotation.XmlAccessorType;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.block.BlockChain;
+import org.qortal.controller.LiteNode;
 import org.qortal.data.account.AccountBalanceData;
 import org.qortal.data.account.AccountData;
 import org.qortal.data.account.RewardShareData;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
+import org.qortal.settings.Settings;
 import org.qortal.utils.Base58;
 
 @XmlAccessorType(XmlAccessType.NONE) // Stops JAX-RS errors when unmarshalling blockchain config
@@ -59,7 +61,17 @@ public class Account {
 	// Balance manipulations - assetId is 0 for QORT
 
 	public long getConfirmedBalance(long assetId) throws DataException {
-		AccountBalanceData accountBalanceData = this.repository.getAccountRepository().getBalance(this.address, assetId);
+		AccountBalanceData accountBalanceData;
+
+		if (Settings.getInstance().isLite()) {
+			// Lite nodes request data from peers instead of the local db
+			accountBalanceData = LiteNode.getInstance().fetchAccountBalance(this.address, assetId);
+		}
+		else {
+			// All other node types fetch from the local db
+			accountBalanceData = this.repository.getAccountRepository().getBalance(this.address, assetId);
+		}
+
 		if (accountBalanceData == null)
 			return 0;
 

src/main/java/org/qortal/account/PrivateKeyAccount.java

@@ -11,15 +11,15 @@ public class PrivateKeyAccount extends PublicKeyAccount {
 	private final Ed25519PrivateKeyParameters edPrivateKeyParams;
 
 	/**
-	 * Create PrivateKeyAccount using byte[32] seed.
+	 * Create PrivateKeyAccount using byte[32] private key.
 	 * 
-	 * @param seed
+	 * @param privateKey
 	 *            byte[32] used to create private/public key pair
 	 * @throws IllegalArgumentException
-	 *             if passed invalid seed
+	 *             if passed invalid privateKey
 	 */
-	public PrivateKeyAccount(Repository repository, byte[] seed) {
-		this(repository, new Ed25519PrivateKeyParameters(seed, 0));
+	public PrivateKeyAccount(Repository repository, byte[] privateKey) {
+		this(repository, new Ed25519PrivateKeyParameters(privateKey, 0));
 	}
 
 	private PrivateKeyAccount(Repository repository, Ed25519PrivateKeyParameters edPrivateKeyParams) {
@@ -37,10 +37,6 @@ public class PrivateKeyAccount extends PublicKeyAccount {
 		return this.privateKey;
 	}
 
-	public static byte[] toPublicKey(byte[] seed) {
-		return new Ed25519PrivateKeyParameters(seed, 0).generatePublicKey().getEncoded();
-	}
-
 	public byte[] sign(byte[] message) {
 		return Crypto.sign(this.edPrivateKeyParams, message);
 	}

src/main/java/org/qortal/api/model/ConnectedPeer.java

@@ -1,7 +1,7 @@
 package org.qortal.api.model;
 
 import io.swagger.v3.oas.annotations.media.Schema;
-import org.qortal.data.network.PeerChainTipData;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.network.PeerData;
 import org.qortal.network.Handshake;
 import org.qortal.network.Peer;
@@ -63,11 +63,11 @@ public class ConnectedPeer {
             this.age = "connecting...";
         }
 
-        PeerChainTipData peerChainTipData = peer.getChainTipData();
+        BlockSummaryData peerChainTipData = peer.getChainTipData();
         if (peerChainTipData != null) {
-            this.lastHeight = peerChainTipData.getLastHeight();
-            this.lastBlockSignature = peerChainTipData.getLastBlockSignature();
-            this.lastBlockTimestamp = peerChainTipData.getLastBlockTimestamp();
+            this.lastHeight = peerChainTipData.getHeight();
+            this.lastBlockSignature = peerChainTipData.getSignature();
+            this.lastBlockTimestamp = peerChainTipData.getTimestamp();
         }
     }
 

src/main/java/org/qortal/api/model/NodeInfo.java

@@ -12,6 +12,7 @@ public class NodeInfo {
 	public long buildTimestamp;
 	public String nodeId;
 	public boolean isTestNet;
+	public String type;
 
 	public NodeInfo() {
 	}

src/main/java/org/qortal/api/model/NodeStatus.java

@@ -4,6 +4,7 @@ import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 
 import org.qortal.controller.Controller;
+import org.qortal.controller.OnlineAccountsManager;
 import org.qortal.controller.Synchronizer;
 import org.qortal.network.Network;
 
@@ -21,7 +22,7 @@ public class NodeStatus {
 	public final int height;
 
 	public NodeStatus() {
-		this.isMintingPossible = Controller.getInstance().isMintingPossible();
+		this.isMintingPossible = OnlineAccountsManager.getInstance().hasActiveOnlineAccountSignatures();
 
 		this.syncPercent = Synchronizer.getInstance().getSyncPercent();
 		this.isSynchronizing = Synchronizer.getInstance().isSynchronizing();

src/main/java/org/qortal/api/model/crosschain/DigibyteSendRequest.java

@@ -0,0 +1,29 @@
+package org.qortal.api.model.crosschain;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class DigibyteSendRequest {
+
+	@Schema(description = "Digibyte BIP32 extended private key", example = "tprv___________________________________________________________________________________________________________")
+	public String xprv58;
+
+	@Schema(description = "Recipient's Digibyte address ('legacy' P2PKH only)", example = "1DigByteEaterAddressDontSendf59kuE")
+	public String receivingAddress;
+
+	@Schema(description = "Amount of DGB to send", type = "number")
+	@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
+	public long digibyteAmount;
+
+	@Schema(description = "Transaction fee per byte (optional). Default is 0.00000100 DGB (100 sats) per byte", example = "0.00000100", type = "number")
+	@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
+	public Long feePerByte;
+
+	public DigibyteSendRequest() {
+	}
+
+}

src/main/java/org/qortal/api/model/crosschain/PirateChainSendRequest.java

@@ -0,0 +1,32 @@
+package org.qortal.api.model.crosschain;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class PirateChainSendRequest {
+
+	@Schema(description = "32 bytes of entropy, Base58 encoded", example = "5oSXF53qENtdUyKhqSxYzP57m6RhVFP9BJKRr9E5kRGV")
+	public String entropy58;
+
+	@Schema(description = "Recipient's Pirate Chain address", example = "zc...")
+	public String receivingAddress;
+
+	@Schema(description = "Amount of ARRR to send", type = "number")
+	@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
+	public long arrrAmount;
+
+	@Schema(description = "Transaction fee per byte (optional). Default is 0.00000100 ARRR (100 sats) per byte", example = "0.00000100", type = "number")
+	@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
+	public Long feePerByte;
+
+	@Schema(description = "Optional memo to include information for the recipient", example = "zc...")
+	public String memo;
+
+	public PirateChainSendRequest() {
+	}
+
+}

src/main/java/org/qortal/api/resource/AddressesResource.java

@@ -30,6 +30,7 @@ import org.qortal.api.Security;
 import org.qortal.api.model.ApiOnlineAccount;
 import org.qortal.api.model.RewardShareKeyRequest;
 import org.qortal.asset.Asset;
+import org.qortal.controller.LiteNode;
 import org.qortal.controller.OnlineAccountsManager;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.account.AccountData;
@@ -109,18 +110,26 @@ public class AddressesResource {
 		if (!Crypto.isValidAddress(address))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
 
-		byte[] lastReference = null;
+		AccountData accountData;
 
-		try (final Repository repository = RepositoryManager.getRepository()) {
-			AccountData accountData = repository.getAccountRepository().getAccount(address);
-			// Not found?
-			if (accountData == null)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.ADDRESS_UNKNOWN);
-
-			lastReference = accountData.getReference();
-		} catch (DataException e) {
-			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		if (Settings.getInstance().isLite()) {
+			// Lite nodes request data from peers instead of the local db
+			accountData = LiteNode.getInstance().fetchAccountData(address);
 		}
+		else {
+			// All other node types request data from local db
+			try (final Repository repository = RepositoryManager.getRepository()) {
+				accountData = repository.getAccountRepository().getAccount(address);
+			} catch (DataException e) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+			}
+		}
+
+		// Not found?
+		if (accountData == null)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.ADDRESS_UNKNOWN);
+
+		byte[] lastReference = accountData.getReference();
 
 		if (lastReference == null || lastReference.length == 0)
 			return "false";
@@ -196,6 +205,10 @@ public class AddressesResource {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			List<OnlineAccountLevel> onlineAccountLevels = new ArrayList<>();
 
+			// Prepopulate all levels
+			for (int i=0; i<=10; i++)
+				onlineAccountLevels.add(new OnlineAccountLevel(i, 0));
+
 			for (OnlineAccountData onlineAccountData : onlineAccounts) {
 				try {
 					final int minterLevel = Account.getRewardShareEffectiveMintingLevelIncludingLevelZero(repository, onlineAccountData.getPublicKey());

src/main/java/org/qortal/api/resource/AdminResource.java

@@ -119,10 +119,23 @@ public class AdminResource {
 		nodeInfo.buildTimestamp = Controller.getInstance().getBuildTimestamp();
 		nodeInfo.nodeId = Network.getInstance().getOurNodeId();
 		nodeInfo.isTestNet = Settings.getInstance().isTestNet();
+		nodeInfo.type = getNodeType();
 
 		return nodeInfo;
 	}
 
+	private String getNodeType() {
+		if (Settings.getInstance().isLite()) {
+			return "lite";
+		}
+		else if (Settings.getInstance().isTopOnly()) {
+			return "topOnly";
+		}
+		else {
+			return "full";
+		}
+	}
+
 	@GET
 	@Path("/status")
 	@Operation(
@@ -381,6 +394,10 @@ public class AdminResource {
 			) @QueryParam("limit") Integer limit, @Parameter(
 				ref = "offset"
 			) @QueryParam("offset") Integer offset, @Parameter(
+				name = "tail",
+				description = "Fetch most recent log lines",
+				schema = @Schema(type = "boolean")
+			) @QueryParam("tail") Boolean tail, @Parameter(
 				ref = "reverse"
 			) @QueryParam("reverse") Boolean reverse) {
 		LoggerContext loggerContext = (LoggerContext) LogManager.getContext();
@@ -396,6 +413,13 @@ public class AdminResource {
 			if (reverse != null && reverse)
 				logLines = Lists.reverse(logLines);
 
+			// Tail mode - return the last X lines (where X = limit)
+			if (tail != null && tail) {
+				if (limit != null && limit > 0) {
+					offset = logLines.size() - limit;
+				}
+			}
+
 			// offset out of bounds?
 			if (offset != null && (offset < 0 || offset >= logLines.size()))
 				return "";
@@ -416,7 +440,7 @@ public class AdminResource {
 
 			limit = Math.min(limit, logLines.size());
 
-			logLines.subList(limit - 1, logLines.size()).clear();
+			logLines.subList(limit, logLines.size()).clear();
 
 			return String.join("\n", logLines);
 		} catch (IOException e) {
@@ -704,6 +728,49 @@ public class AdminResource {
 		}
 	}
 
+	@POST
+	@Path("/repository/importarchivedtrades")
+	@Operation(
+			summary = "Imports archived trades from TradeBotStatesArchive.json",
+			description = "This can be used to recover trades that exist in the archive only, which may be needed if a<br />" +
+					"problem occurred during the proof-of-work computation stage of a buy request.",
+			responses = {
+					@ApiResponse(
+							content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "boolean"))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public boolean importArchivedTrades(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+		Security.checkApiCallAllowed(request);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+
+			blockchainLock.lockInterruptibly();
+
+			try {
+				repository.importDataFromFile("qortal-backup/TradeBotStatesArchive.json");
+				repository.saveChanges();
+
+				return true;
+
+			} catch (IOException e) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA, e);
+
+			} finally {
+				blockchainLock.unlock();
+			}
+		} catch (InterruptedException e) {
+			// We couldn't lock blockchain to perform import
+			return false;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+
 
 	@POST
 	@Path("/apikey/generate")

src/main/java/org/qortal/api/resource/ArbitraryResource.java

@@ -12,10 +12,10 @@ import io.swagger.v3.oas.annotations.security.SecurityRequirement;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
 import java.io.*;
-import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 
 import javax.servlet.ServletContext;
@@ -45,6 +45,7 @@ import org.qortal.data.arbitrary.*;
 import org.qortal.data.naming.NameData;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.TransactionData;
+import org.qortal.list.ResourceListManager;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
@@ -56,7 +57,9 @@ import org.qortal.transaction.Transaction.ValidationResult;
 import org.qortal.transform.TransformationException;
 import org.qortal.transform.transaction.ArbitraryTransactionTransformer;
 import org.qortal.transform.transaction.TransactionTransformer;
+import org.qortal.utils.ArbitraryTransactionUtils;
 import org.qortal.utils.Base58;
+import org.qortal.utils.NTP;
 import org.qortal.utils.ZipUtils;
 
 @Path("/arbitrary")
@@ -90,6 +93,7 @@ public class ArbitraryResource {
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
+			@Parameter(description = "Filter names by list") @QueryParam("namefilter") String nameFilter,
 			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
 			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata) {
 
@@ -106,8 +110,18 @@ public class ArbitraryResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "identifier cannot be specified when requesting a default resource");
 			}
 
+			// Load filter from list if needed
+			List<String> names = null;
+			if (nameFilter != null) {
+				names = ResourceListManager.getInstance().getStringsInList(nameFilter);
+				if (names.isEmpty()) {
+					// List doesn't exist or is empty - so there will be no matches
+					return new ArrayList<>();
+				}
+			}
+
 			List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-					.getArbitraryResources(service, identifier, null, defaultRes, limit, offset, reverse);
+					.getArbitraryResources(service, identifier, names, defaultRes, limit, offset, reverse);
 
 			if (resources == null) {
 				return new ArrayList<>();
@@ -215,7 +229,7 @@ public class ArbitraryResource {
 				String name = creatorName.name;
 				if (name != null) {
 					List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-							.getArbitraryResources(service, identifier, name, defaultRes, null, null, reverse);
+							.getArbitraryResources(service, identifier, Arrays.asList(name), defaultRes, null, null, reverse);
 
 					if (includeStatus != null && includeStatus) {
 						resources = this.addStatusToResources(resources);
@@ -253,7 +267,7 @@ public class ArbitraryResource {
 															@QueryParam("build") Boolean build) {
 
 		Security.requirePriorAuthorizationOrApiKey(request, name, service, null);
-		return this.getStatus(service, name, null, build);
+		return ArbitraryTransactionUtils.getStatus(service, name, null, build);
 	}
 
 	@GET
@@ -275,7 +289,7 @@ public class ArbitraryResource {
 													 @QueryParam("build") Boolean build) {
 
 		Security.requirePriorAuthorizationOrApiKey(request, name, service, identifier);
-		return this.getStatus(service, name, identifier, build);
+		return ArbitraryTransactionUtils.getStatus(service, name, identifier, build);
 	}
 
 
@@ -1099,7 +1113,8 @@ public class ArbitraryResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, error);
 			}
 
-			if (!Controller.getInstance().isUpToDate()) {
+			final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
+			if (!Controller.getInstance().isUpToDate(minLatestBlockTimestamp)) {
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCKCHAIN_NEEDS_SYNC);
 			}
 
@@ -1245,24 +1260,6 @@ public class ArbitraryResource {
 	}
 
 
-	private ArbitraryResourceStatus getStatus(Service service, String name, String identifier, Boolean build) {
-
-		// If "build=true" has been specified in the query string, build the resource before returning its status
-		if (build != null && build == true) {
-			ArbitraryDataReader reader = new ArbitraryDataReader(name, ArbitraryDataFile.ResourceIdType.NAME, service, null);
-			try {
-				if (!reader.isBuilding()) {
-					reader.loadSynchronously(false);
-				}
-			} catch (Exception e) {
-				// No need to handle exception, as it will be reflected in the status
-			}
-		}
-
-		ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
-		return resource.getStatus(false);
-	}
-
 	private List<ArbitraryResourceInfo> addStatusToResources(List<ArbitraryResourceInfo> resources) {
 		// Determine and add the status of each resource
 		List<ArbitraryResourceInfo> updatedResources = new ArrayList<>();

src/main/java/org/qortal/api/resource/BlocksResource.java

@@ -114,7 +114,7 @@ public class BlocksResource {
 	@Path("/signature/{signature}/data")
 	@Operation(
 			summary = "Fetch serialized, base58 encoded block data using base58 signature",
-			description = "Returns serialized data for the block that matches the given signature",
+			description = "Returns serialized data for the block that matches the given signature, and an optional block serialization version",
 			responses = {
 					@ApiResponse(
 							description = "the block data",
@@ -125,7 +125,7 @@ public class BlocksResource {
 	@ApiErrors({
 			ApiError.INVALID_SIGNATURE, ApiError.BLOCK_UNKNOWN, ApiError.INVALID_DATA, ApiError.REPOSITORY_ISSUE
 	})
-	public String getSerializedBlockData(@PathParam("signature") String signature58) {
+	public String getSerializedBlockData(@PathParam("signature") String signature58, @QueryParam("version") Integer version) {
 		// Decode signature
 		byte[] signature;
 		try {
@@ -136,20 +136,41 @@ public class BlocksResource {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 
+			// Default to version 1
+			if (version == null) {
+				version = 1;
+			}
+
             // Check the database first
 			BlockData blockData = repository.getBlockRepository().fromSignature(signature);
 			if (blockData != null) {
                 Block block = new Block(repository, blockData);
                 ByteArrayOutputStream bytes = new ByteArrayOutputStream();
                 bytes.write(Ints.toByteArray(block.getBlockData().getHeight()));
-                bytes.write(BlockTransformer.toBytes(block));
+
+				switch (version) {
+					case 1:
+						bytes.write(BlockTransformer.toBytes(block));
+						break;
+
+					case 2:
+						bytes.write(BlockTransformer.toBytesV2(block));
+						break;
+
+					default:
+						throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+				}
+
                 return Base58.encode(bytes.toByteArray());
             }
 
             // Not found, so try the block archive
             byte[] bytes = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, false, repository);
             if (bytes != null) {
-                return Base58.encode(bytes);
+				if (version != 1) {
+					throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Archived blocks require version 1");
+				}
+				return Base58.encode(bytes);
             }
 
             throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCK_UNKNOWN);

src/main/java/org/qortal/api/resource/ChatResource.java

@@ -69,6 +69,7 @@ public class ChatResource {
 	public List<ChatMessage> searchChat(@QueryParam("before") Long before, @QueryParam("after") Long after,
 			@QueryParam("txGroupId") Integer txGroupId,
 			@QueryParam("involving") List<String> involvingAddresses,
+			@QueryParam("reference") String reference,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
@@ -87,11 +88,16 @@ public class ChatResource {
 		if (after != null && after < 1500000000000L)
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
+		byte[] referenceBytes = null;
+		if (reference != null)
+			referenceBytes = Base58.decode(reference);
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			return repository.getChatRepository().getMessagesMatchingCriteria(
 					before,
 					after,
 					txGroupId,
+					referenceBytes,
 					involvingAddresses,
 					limit, offset, reverse);
 		} catch (DataException e) {
@@ -99,6 +105,38 @@ public class ChatResource {
 		}
 	}
 
+	@GET
+	@Path("/message/{signature}")
+	@Operation(
+			summary = "Find chat message by signature",
+			responses = {
+					@ApiResponse(
+							description = "CHAT message",
+							content = @Content(
+										schema = @Schema(
+												implementation = ChatMessage.class
+										)
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public ChatMessage getMessageBySignature(@PathParam("signature") String signature58) {
+		byte[] signature = Base58.decode(signature58);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			ChatTransactionData chatTransactionData = (ChatTransactionData) repository.getTransactionRepository().fromSignature(signature);
+			if (chatTransactionData == null) {
+				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Message not found");
+			}
+
+			return repository.getChatRepository().toChatMessage(chatTransactionData);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@GET
 	@Path("/active/{address}")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainDigibyteResource.java

@@ -0,0 +1,177 @@
+package org.qortal.api.resource;
+
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.media.ArraySchema;
+import io.swagger.v3.oas.annotations.media.Content;
+import io.swagger.v3.oas.annotations.media.Schema;
+import io.swagger.v3.oas.annotations.parameters.RequestBody;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+import io.swagger.v3.oas.annotations.security.SecurityRequirement;
+import io.swagger.v3.oas.annotations.tags.Tag;
+
+import java.util.List;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.HeaderParam;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+
+import org.bitcoinj.core.Transaction;
+import org.qortal.api.ApiError;
+import org.qortal.api.ApiErrors;
+import org.qortal.api.ApiExceptionFactory;
+import org.qortal.api.Security;
+import org.qortal.api.model.crosschain.DigibyteSendRequest;
+import org.qortal.crosschain.Digibyte;
+import org.qortal.crosschain.ForeignBlockchainException;
+import org.qortal.crosschain.SimpleTransaction;
+
+@Path("/crosschain/dgb")
+@Tag(name = "Cross-Chain (Digibyte)")
+public class CrossChainDigibyteResource {
+
+	@Context
+	HttpServletRequest request;
+
+	@POST
+	@Path("/walletbalance")
+	@Operation(
+		summary = "Returns DGB balance for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string", description = "balance (satoshis)"))
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getDigibyteWalletBalance(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Digibyte digibyte = Digibyte.getInstance();
+
+		if (!digibyte.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			Long balance = digibyte.getWalletBalanceFromTransactions(key58);
+			if (balance == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return balance.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
+	@POST
+	@Path("/wallettransactions")
+	@Operation(
+		summary = "Returns transactions for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public List<SimpleTransaction> getDigibyteWalletTransactions(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Digibyte digibyte = Digibyte.getInstance();
+
+		if (!digibyte.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return digibyte.getWalletTransactions(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
+	@POST
+	@Path("/send")
+	@Operation(
+		summary = "Sends DGB from hierarchical, deterministic BIP32 wallet to specific address",
+		description = "Currently supports 'legacy' P2PKH Digibyte addresses and Native SegWit (P2WPKH) addresses. Supply BIP32 'm' private key in base58, starting with 'xprv' for mainnet, 'tprv' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.APPLICATION_JSON,
+				schema = @Schema(
+					implementation = DigibyteSendRequest.class
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string", description = "transaction hash"))
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.FOREIGN_BLOCKCHAIN_BALANCE_ISSUE, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String sendBitcoin(@HeaderParam(Security.API_KEY_HEADER) String apiKey, DigibyteSendRequest digibyteSendRequest) {
+		Security.checkApiCallAllowed(request);
+
+		if (digibyteSendRequest.digibyteAmount <= 0)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		if (digibyteSendRequest.feePerByte != null && digibyteSendRequest.feePerByte <= 0)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		Digibyte digibyte = Digibyte.getInstance();
+
+		if (!digibyte.isValidAddress(digibyteSendRequest.receivingAddress))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
+
+		if (!digibyte.isValidDeterministicKey(digibyteSendRequest.xprv58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		Transaction spendTransaction = digibyte.buildSpend(digibyteSendRequest.xprv58,
+				digibyteSendRequest.receivingAddress,
+				digibyteSendRequest.digibyteAmount,
+				digibyteSendRequest.feePerByte);
+
+		if (spendTransaction == null)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_BALANCE_ISSUE);
+
+		try {
+			digibyte.broadcastTransaction(spendTransaction);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+
+		return spendTransaction.getTxId().toString();
+	}
+
+}

src/main/java/org/qortal/api/resource/CrossChainHtlcResource.java

@@ -1,5 +1,6 @@
 package org.qortal.api.resource;
 
+import com.google.common.hash.HashCode;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.media.Content;
 import io.swagger.v3.oas.annotations.media.Schema;
@@ -7,8 +8,11 @@ import io.swagger.v3.oas.annotations.responses.ApiResponse;
 import io.swagger.v3.oas.annotations.security.SecurityRequirement;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
+import java.io.IOException;
 import java.math.BigDecimal;
 import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.locks.ReentrantLock;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.*;
@@ -21,6 +25,7 @@ import org.bitcoinj.core.*;
 import org.bitcoinj.script.Script;
 import org.qortal.api.*;
 import org.qortal.api.model.CrossChainBitcoinyHTLCStatus;
+import org.qortal.controller.Controller;
 import org.qortal.crosschain.*;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.at.ATData;
@@ -284,6 +289,12 @@ public class CrossChainHtlcResource {
 					continue;
 				}
 
+				Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
+				if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+					LOGGER.info("Skipping AT {} because ARRR is currently unsupported", atAddress);
+					continue;
+				}
+
 				CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atData);
 				if (crossChainTradeData == null) {
 					LOGGER.info("Couldn't find crosschain trade data for AT {}", atAddress);
@@ -363,10 +374,6 @@ public class CrossChainHtlcResource {
 			// Use secret-A to redeem P2SH-A
 
 			Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
-			if (bitcoiny.getClass() == Bitcoin.class) {
-				LOGGER.info("Redeeming a Bitcoin HTLC is not yet supported");
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
-			}
 
 			int lockTime = crossChainTradeData.lockTimeA;
 			byte[] redeemScriptA = BitcoinyHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTime, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
@@ -574,7 +581,7 @@ public class CrossChainHtlcResource {
 			// If the AT is "finished" then it will have a zero balance
 			// In these cases we should avoid HTLC refunds if tbe QORT haven't been returned to the seller
 			if (atData.getIsFinished() && crossChainTradeData.mode != AcctMode.REFUNDED && crossChainTradeData.mode != AcctMode.CANCELLED) {
-				LOGGER.info(String.format("Skipping AT %s because the QORT has already been redemed", atAddress));
+				LOGGER.info(String.format("Skipping AT %s because the QORT has already been redeemed by the buyer", atAddress));
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 			}
 
@@ -584,11 +591,6 @@ public class CrossChainHtlcResource {
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
 			Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
-			if (bitcoiny.getClass() == Bitcoin.class) {
-				LOGGER.info("Refunding a Bitcoin HTLC is not yet supported");
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
-			}
-
 			int lockTime = tradeBotData.getLockTimeA();
 
 			// We can't refund P2SH-A until lockTime-A has passed
@@ -600,15 +602,26 @@ public class CrossChainHtlcResource {
 			if (medianBlockTime <= lockTime)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
 
-			byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-			String p2shAddressA = bitcoiny.deriveP2shAddress(redeemScriptA);
-			LOGGER.info(String.format("Refunding P2SH address: %s", p2shAddressA));
-
 			// Fee for redeem/refund is subtracted from P2SH-A balance.
 			long feeTimestamp = calcFeeTimestamp(lockTime, crossChainTradeData.tradeTimeout);
 			long p2shFee = bitcoiny.getP2shFee(feeTimestamp);
 			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+
+			// Create redeem script based on destination chain
+			byte[] redeemScriptA;
+			String p2shAddressA;
+			BitcoinyHTLC.Status htlcStatusA;
+			if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+				redeemScriptA = PirateChainHTLC.buildScript(tradeBotData.getTradeForeignPublicKey(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+				p2shAddressA = PirateChain.getInstance().deriveP2shAddressBPrefix(redeemScriptA);
+				htlcStatusA = PirateChainHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+			}
+			else {
+				redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+				p2shAddressA = bitcoiny.deriveP2shAddress(redeemScriptA);
+				htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+			}
+			LOGGER.info(String.format("Refunding P2SH address: %s", p2shAddressA));
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -625,18 +638,45 @@ public class CrossChainHtlcResource {
 
 				case FUNDED:{
 					Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-					ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-					List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
 
-					// Validate the destination foreign blockchain address
-					Address receiving = Address.fromString(bitcoiny.getNetworkParameters(), receiveAddress);
-					if (receiving.getOutputScriptType() != Script.ScriptType.P2PKH)
-						throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+					if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+						// Pirate Chain custom integration
 
-					Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
-							fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
+						PirateChain pirateChain = PirateChain.getInstance();
+						String p2shAddressT3 = pirateChain.deriveP2shAddress(redeemScriptA);
+
+						// Get funding txid
+						String fundingTxidHex = PirateChainHTLC.getUnspentFundingTxid(pirateChain.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+						if (fundingTxidHex == null) {
+							throw new ForeignBlockchainException("Missing funding txid when refunding P2SH");
+						}
+						String fundingTxid58 = Base58.encode(HashCode.fromString(fundingTxidHex).asBytes());
+
+						byte[] privateKey = tradeBotData.getTradePrivateKey();
+						String privateKey58 = Base58.encode(privateKey);
+						String redeemScript58 = Base58.encode(redeemScriptA);
+
+						String txid = PirateChain.getInstance().refundP2sh(p2shAddressT3,
+								receiveAddress, refundAmount.value, redeemScript58, fundingTxid58, lockTime, privateKey58);
+						LOGGER.info("Refund txid: {}", txid);
+					}
+					else {
+						// ElectrumX coins
+
+						ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
+						List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
+
+						// Validate the destination foreign blockchain address
+						Address receiving = Address.fromString(bitcoiny.getNetworkParameters(), receiveAddress);
+						if (receiving.getOutputScriptType() != Script.ScriptType.P2PKH)
+							throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+						Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
+								fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
+
+						bitcoiny.broadcastTransaction(p2shRefundTransaction);
+					}
 
-					bitcoiny.broadcastTransaction(p2shRefundTransaction);
 					return true;
 				}
 			}

src/main/java/org/qortal/api/resource/CrossChainPirateChainResource.java

@@ -0,0 +1,229 @@
+package org.qortal.api.resource;
+
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.media.ArraySchema;
+import io.swagger.v3.oas.annotations.media.Content;
+import io.swagger.v3.oas.annotations.media.Schema;
+import io.swagger.v3.oas.annotations.parameters.RequestBody;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+import io.swagger.v3.oas.annotations.security.SecurityRequirement;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import org.qortal.api.ApiError;
+import org.qortal.api.ApiErrors;
+import org.qortal.api.ApiExceptionFactory;
+import org.qortal.api.Security;
+import org.qortal.api.model.crosschain.PirateChainSendRequest;
+import org.qortal.crosschain.ForeignBlockchainException;
+import org.qortal.crosschain.PirateChain;
+import org.qortal.crosschain.SimpleTransaction;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.HeaderParam;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+import java.util.List;
+
+@Path("/crosschain/arrr")
+@Tag(name = "Cross-Chain (Pirate Chain)")
+public class CrossChainPirateChainResource {
+
+	@Context
+	HttpServletRequest request;
+
+	@POST
+	@Path("/walletbalance")
+	@Operation(
+		summary = "Returns ARRR balance",
+		description = "Supply 32 bytes of entropy, Base58 encoded",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+						type = "string",
+						description = "32 bytes of entropy, Base58 encoded",
+						example = "5oSXF53qENtdUyKhqSxYzP57m6RhVFP9BJKRr9E5kRGV"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string", description = "balance (satoshis)"))
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getPirateChainWalletBalance(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String entropy58) {
+		Security.checkApiCallAllowed(request);
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			Long balance = pirateChain.getWalletBalance(entropy58);
+			if (balance == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return balance.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE, e.getMessage());
+		}
+	}
+
+	@POST
+	@Path("/wallettransactions")
+	@Operation(
+		summary = "Returns transactions",
+		description = "Supply 32 bytes of entropy, Base58 encoded",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+						type = "string",
+						description = "32 bytes of entropy, Base58 encoded",
+						example = "5oSXF53qENtdUyKhqSxYzP57m6RhVFP9BJKRr9E5kRGV"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public List<SimpleTransaction> getPirateChainWalletTransactions(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String entropy58) {
+		Security.checkApiCallAllowed(request);
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			return pirateChain.getWalletTransactions(entropy58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE, e.getMessage());
+		}
+	}
+
+	@POST
+	@Path("/send")
+	@Operation(
+		summary = "Sends ARRR from wallet",
+		description = "Currently supports 'legacy' P2PKH PirateChain addresses and Native SegWit (P2WPKH) addresses. Supply BIP32 'm' private key in base58, starting with 'xprv' for mainnet, 'tprv' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+						type = "string",
+						description = "32 bytes of entropy, Base58 encoded",
+						example = "5oSXF53qENtdUyKhqSxYzP57m6RhVFP9BJKRr9E5kRGV"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string", description = "transaction hash"))
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.FOREIGN_BLOCKCHAIN_BALANCE_ISSUE, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String sendBitcoin(@HeaderParam(Security.API_KEY_HEADER) String apiKey, PirateChainSendRequest pirateChainSendRequest) {
+		Security.checkApiCallAllowed(request);
+
+		if (pirateChainSendRequest.arrrAmount <= 0)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		if (pirateChainSendRequest.feePerByte != null && pirateChainSendRequest.feePerByte <= 0)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			return pirateChain.sendCoins(pirateChainSendRequest);
+
+		} catch (ForeignBlockchainException e) {
+			// TODO
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE, e.getMessage());
+		}
+	}
+
+
+	@POST
+	@Path("/walletaddress")
+	@Operation(
+			summary = "Returns main wallet address",
+			description = "Supply 32 bytes of entropy, Base58 encoded",
+			requestBody = @RequestBody(
+					required = true,
+					content = @Content(
+							mediaType = MediaType.TEXT_PLAIN,
+							schema = @Schema(
+									type = "string",
+									description = "32 bytes of entropy, Base58 encoded",
+									example = "5oSXF53qENtdUyKhqSxYzP57m6RhVFP9BJKRr9E5kRGV"
+							)
+					)
+			),
+			responses = {
+					@ApiResponse(
+							content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getPirateChainWalletAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String entropy58) {
+		Security.checkApiCallAllowed(request);
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			return pirateChain.getWalletAddress(entropy58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE, e.getMessage());
+		}
+	}
+
+
+	@POST
+	@Path("/syncstatus")
+	@Operation(
+			summary = "Returns synchronization status",
+			description = "Supply 32 bytes of entropy, Base58 encoded",
+			requestBody = @RequestBody(
+					required = true,
+					content = @Content(
+							mediaType = MediaType.TEXT_PLAIN,
+							schema = @Schema(
+									type = "string",
+									description = "32 bytes of entropy, Base58 encoded",
+									example = "5oSXF53qENtdUyKhqSxYzP57m6RhVFP9BJKRr9E5kRGV"
+							)
+					)
+			),
+			responses = {
+					@ApiResponse(
+							content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getPirateChainSyncStatus(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String entropy58) {
+		Security.checkApiCallAllowed(request);
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			return pirateChain.getSyncStatus(entropy58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE, e.getMessage());
+		}
+	}
+}

src/main/java/org/qortal/api/resource/CrossChainTradeBotResource.java

@@ -42,6 +42,7 @@ import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 import org.qortal.utils.Base58;
+import org.qortal.utils.NTP;
 
 @Path("/crosschain/tradebot")
 @Tag(name = "Cross-Chain (Trade-Bot)")
@@ -137,7 +138,8 @@ public class CrossChainTradeBotResource {
 		if (tradeBotCreateRequest.qortAmount <= 0 || tradeBotCreateRequest.fundingQortAmount <= 0)
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.ORDER_SIZE_TOO_SMALL);
 
-		if (!Controller.getInstance().isUpToDate())
+		final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
+		if (!Controller.getInstance().isUpToDate(minLatestBlockTimestamp))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCKCHAIN_NEEDS_SYNC);
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
@@ -153,7 +155,7 @@ public class CrossChainTradeBotResource {
 
 			return Base58.encode(unsignedBytes);
 		} catch (DataException e) {
-			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
 		}
 	}
 
@@ -198,7 +200,8 @@ public class CrossChainTradeBotResource {
 		if (tradeBotRespondRequest.receivingAddress == null || !Crypto.isValidAddress(tradeBotRespondRequest.receivingAddress))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
 
-		if (!Controller.getInstance().isUpToDate())
+		final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
+		if (!Controller.getInstance().isUpToDate(minLatestBlockTimestamp))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCKCHAIN_NEEDS_SYNC);
 
 		// Extract data from cross-chain trading AT
@@ -237,7 +240,7 @@ public class CrossChainTradeBotResource {
 					return "false";
 			}
 		} catch (DataException e) {
-			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
 		}
 	}
 

src/main/java/org/qortal/api/resource/NamesResource.java

@@ -26,6 +26,7 @@ import org.qortal.api.ApiErrors;
 import org.qortal.api.ApiException;
 import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.model.NameSummary;
+import org.qortal.controller.LiteNode;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.naming.NameData;
 import org.qortal.data.transaction.BuyNameTransactionData;
@@ -101,7 +102,14 @@ public class NamesResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			List<NameData> names = repository.getNameRepository().getNamesByOwner(address, limit, offset, reverse);
+			List<NameData> names;
+
+			if (Settings.getInstance().isLite()) {
+				names = LiteNode.getInstance().fetchAccountNames(address);
+			}
+			else {
+				names = repository.getNameRepository().getNamesByOwner(address, limit, offset, reverse);
+			}
 
 			return names.stream().map(NameSummary::new).collect(Collectors.toList());
 		} catch (DataException e) {
@@ -126,10 +134,18 @@ public class NamesResource {
 	@ApiErrors({ApiError.NAME_UNKNOWN, ApiError.REPOSITORY_ISSUE})
 	public NameData getName(@PathParam("name") String name) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			NameData nameData = repository.getNameRepository().fromName(name);
+			NameData nameData;
 
-			if (nameData == null)
+			if (Settings.getInstance().isLite()) {
+				nameData = LiteNode.getInstance().fetchNameData(name);
+			}
+			else {
+				nameData = repository.getNameRepository().fromName(name);
+			}
+
+			if (nameData == null) {
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.NAME_UNKNOWN);
+			}
 
 			return nameData;
 		} catch (ApiException e) {

src/main/java/org/qortal/api/resource/PeersResource.java

@@ -20,6 +20,11 @@ import javax.ws.rs.*;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.core.config.Configuration;
+import org.apache.logging.log4j.core.config.LoggerConfig;
+import org.apache.logging.log4j.core.LoggerContext;
 import org.qortal.api.*;
 import org.qortal.api.model.ConnectedPeer;
 import org.qortal.api.model.PeersSummary;
@@ -127,9 +132,29 @@ public class PeersResource {
 		}
 	)
 	@SecurityRequirement(name = "apiKey")
-	public ExecuteProduceConsume.StatsSnapshot getEngineStats(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+	public ExecuteProduceConsume.StatsSnapshot getEngineStats(@HeaderParam(Security.API_KEY_HEADER) String apiKey, @QueryParam("newLoggingLevel") Level newLoggingLevel) {
 		Security.checkApiCallAllowed(request);
 
+		if (newLoggingLevel != null) {
+			final LoggerContext ctx = (LoggerContext) LogManager.getContext(false);
+			final Configuration config = ctx.getConfiguration();
+
+			String epcClassName = "org.qortal.network.Network.NetworkProcessor";
+			LoggerConfig loggerConfig = config.getLoggerConfig(epcClassName);
+			LoggerConfig specificConfig = loggerConfig;
+
+			// We need a specific configuration for this logger,
+			// otherwise we would change the level of all other loggers
+			// having the original configuration as parent as well
+			if (!loggerConfig.getName().equals(epcClassName)) {
+				specificConfig = new LoggerConfig(epcClassName, newLoggingLevel, true);
+				specificConfig.setParent(loggerConfig);
+				config.addLogger(epcClassName, specificConfig);
+			}
+			specificConfig.setLevel(newLoggingLevel);
+			ctx.updateLoggers();
+		}
+
 		return Network.getInstance().getStatsSnapshot();
 	}
 

src/main/java/org/qortal/api/resource/TransactionsResource.java

@@ -12,6 +12,7 @@ import io.swagger.v3.oas.annotations.tags.Tag;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReentrantLock;
@@ -32,6 +33,8 @@ import org.qortal.api.ApiException;
 import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.model.SimpleTransactionSignRequest;
 import org.qortal.controller.Controller;
+import org.qortal.controller.LiteNode;
+import org.qortal.crypto.Crypto;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.globalization.Translator;
 import org.qortal.repository.DataException;
@@ -250,14 +253,29 @@ public class TransactionsResource {
 		ApiError.REPOSITORY_ISSUE
 	})
 	public List<TransactionData> getUnconfirmedTransactions(@Parameter(
+			description = "A list of transaction types"
+	) @QueryParam("txType") List<TransactionType> txTypes, @Parameter(
+			description = "Transaction creator's base58 encoded public key"
+	) @QueryParam("creator") String creatorPublicKey58, @Parameter(
 		ref = "limit"
 	) @QueryParam("limit") Integer limit, @Parameter(
 		ref = "offset"
 	) @QueryParam("offset") Integer offset, @Parameter(
 		ref = "reverse"
 	) @QueryParam("reverse") Boolean reverse) {
+
+		// Decode public key if supplied
+		byte[] creatorPublicKey = null;
+		if (creatorPublicKey58 != null) {
+			try {
+				creatorPublicKey = Base58.decode(creatorPublicKey58);
+			} catch (NumberFormatException e) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PUBLIC_KEY, e);
+			}
+		}
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			return repository.getTransactionRepository().getUnconfirmedTransactions(limit, offset, reverse);
+			return repository.getTransactionRepository().getUnconfirmedTransactions(txTypes, creatorPublicKey, limit, offset, reverse);
 		} catch (ApiException e) {
 			throw e;
 		} catch (DataException e) {
@@ -366,6 +384,73 @@ public class TransactionsResource {
 		}
 	}
 
+	@GET
+	@Path("/address/{address}")
+	@Operation(
+			summary = "Returns transactions for given address",
+			responses = {
+					@ApiResponse(
+							description = "transactions",
+							content = @Content(
+									array = @ArraySchema(
+											schema = @Schema(
+													implementation = TransactionData.class
+											)
+									)
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_ADDRESS,  ApiError.REPOSITORY_ISSUE})
+	public List<TransactionData> getAddressTransactions(@PathParam("address") String address,
+												 		@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
+												 		@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
+														@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
+		if (!Crypto.isValidAddress(address)) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
+		}
+
+		if (limit == null) {
+			limit = 0;
+		}
+		if (offset == null) {
+			offset = 0;
+		}
+
+		List<TransactionData> transactions;
+
+		if (Settings.getInstance().isLite()) {
+			// Fetch from network
+			transactions = LiteNode.getInstance().fetchAccountTransactions(address, limit, offset);
+
+			// Sort the data, since we can't guarantee the order that a peer sent it in
+			if (reverse) {
+				transactions.sort(Comparator.comparingLong(TransactionData::getTimestamp).reversed());
+			} else {
+				transactions.sort(Comparator.comparingLong(TransactionData::getTimestamp));
+			}
+		}
+		else {
+			// Fetch from local db
+			try (final Repository repository = RepositoryManager.getRepository()) {
+				List<byte[]> signatures = repository.getTransactionRepository().getSignaturesMatchingCriteria(null, null, null,
+						null, null, null, address, TransactionsResource.ConfirmationStatus.CONFIRMED, limit, offset, reverse);
+
+				// Expand signatures to transactions
+				transactions = new ArrayList<>(signatures.size());
+				for (byte[] signature : signatures) {
+					transactions.add(repository.getTransactionRepository().fromSignature(signature));
+				}
+			} catch (ApiException e) {
+				throw e;
+			} catch (DataException e) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+			}
+		}
+
+		return transactions;
+	}
+
 	@GET
 	@Path("/unitfee")
 	@Operation(
@@ -638,9 +723,9 @@ public class TransactionsResource {
 		ApiError.BLOCKCHAIN_NEEDS_SYNC, ApiError.INVALID_SIGNATURE, ApiError.INVALID_DATA, ApiError.TRANSFORMATION_ERROR, ApiError.REPOSITORY_ISSUE
 	})
 	public String processTransaction(String rawBytes58) {
-		// Only allow a transaction to be processed if our latest block is less than 30 minutes old
+		// Only allow a transaction to be processed if our latest block is less than 60 minutes old
 		// If older than this, we should first wait until the blockchain is synced
-		final Long minLatestBlockTimestamp = NTP.getTime() - (30 * 60 * 1000L);
+		final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
 		if (!Controller.getInstance().isUpToDate(minLatestBlockTimestamp))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCKCHAIN_NEEDS_SYNC);
 
@@ -663,7 +748,7 @@ public class TransactionsResource {
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_SIGNATURE);
 
 			ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
-			if (!blockchainLock.tryLock(30, TimeUnit.SECONDS))
+			if (!blockchainLock.tryLock(60, TimeUnit.SECONDS))
 				throw createTransactionInvalidException(request, ValidationResult.NO_BLOCKCHAIN_LOCK);
 
 			try {

src/main/java/org/qortal/api/websocket/ChatMessagesWebSocket.java

@@ -46,6 +46,7 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 						null,
 						txGroupId,
 						null,
+						null,
 						null, null, null);
 
 				sendMessages(session, chatMessages);
@@ -72,6 +73,7 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 					null,
 					null,
 					null,
+					null,
 					involvingAddresses,
 					null, null, null);
 

src/main/java/org/qortal/api/websocket/TradeBotWebSocket.java

@@ -2,10 +2,7 @@ package org.qortal.api.websocket;
 
 import java.io.IOException;
 import java.io.StringWriter;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.stream.Collectors;
 
 import org.eclipse.jetty.websocket.api.Session;
@@ -85,6 +82,7 @@ public class TradeBotWebSocket extends ApiWebSocket implements Listener {
 	@Override
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		final boolean excludeInitialData = queryParams.get("excludeInitialData") != null;
 
 		List<String> foreignBlockchains = queryParams.get("foreignBlockchain");
 		final String foreignBlockchain = foreignBlockchains == null ? null : foreignBlockchains.get(0);
@@ -98,15 +96,22 @@ public class TradeBotWebSocket extends ApiWebSocket implements Listener {
 		// save session's preferred blockchain (if any)
 		sessionBlockchain.put(session, foreignBlockchain);
 
-		// Send all known trade-bot entries
-		try (final Repository repository = RepositoryManager.getRepository()) {
-			List<TradeBotData> tradeBotEntries = repository.getCrossChainRepository().getAllTradeBotData();
 
-			// Optional filtering
-			if (foreignBlockchain != null)
-				tradeBotEntries = tradeBotEntries.stream()
-						.filter(tradeBotData -> tradeBotData.getForeignBlockchain().equals(foreignBlockchain))
-						.collect(Collectors.toList());
+
+		// Maybe send all known trade-bot entries
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			List<TradeBotData> tradeBotEntries = new ArrayList<>();
+
+			// We might need to exclude the initial data from the response
+			if (!excludeInitialData) {
+				tradeBotEntries = repository.getCrossChainRepository().getAllTradeBotData();
+
+				// Optional filtering
+				if (foreignBlockchain != null)
+					tradeBotEntries = tradeBotEntries.stream()
+							.filter(tradeBotData -> tradeBotData.getForeignBlockchain().equals(foreignBlockchain))
+							.collect(Collectors.toList());
+			}
 
 			if (!sendEntries(session, tradeBotEntries)) {
 				session.close(4002, "websocket issue");

src/main/java/org/qortal/api/websocket/TradeOffersWebSocket.java

@@ -173,6 +173,7 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
 		final boolean includeHistoric = queryParams.get("includeHistoric") != null;
+		final boolean excludeInitialData = queryParams.get("excludeInitialData") != null;
 
 		List<String> foreignBlockchains = queryParams.get("foreignBlockchain");
 		final String foreignBlockchain = foreignBlockchains == null ? null : foreignBlockchains.get(0);
@@ -189,20 +190,23 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 
 		List<CrossChainOfferSummary> crossChainOfferSummaries = new ArrayList<>();
 
-		synchronized (cachedInfoByBlockchain) {
-			Collection<CachedOfferInfo> cachedInfos;
+		// We might need to exclude the initial data from the response
+		if (!excludeInitialData) {
+			synchronized (cachedInfoByBlockchain) {
+				Collection<CachedOfferInfo> cachedInfos;
 
-			if (foreignBlockchain == null)
-				// No preferred blockchain, so iterate through all of them
-				cachedInfos = cachedInfoByBlockchain.values();
-			else
-				cachedInfos = Collections.singleton(cachedInfoByBlockchain.computeIfAbsent(foreignBlockchain, k -> new CachedOfferInfo()));
+				if (foreignBlockchain == null)
+					// No preferred blockchain, so iterate through all of them
+					cachedInfos = cachedInfoByBlockchain.values();
+				else
+					cachedInfos = Collections.singleton(cachedInfoByBlockchain.computeIfAbsent(foreignBlockchain, k -> new CachedOfferInfo()));
 
-			for (CachedOfferInfo cachedInfo : cachedInfos) {
-				crossChainOfferSummaries.addAll(cachedInfo.currentSummaries.values());
+				for (CachedOfferInfo cachedInfo : cachedInfos) {
+					crossChainOfferSummaries.addAll(cachedInfo.currentSummaries.values());
 
-				if (includeHistoric)
-					crossChainOfferSummaries.addAll(cachedInfo.historicSummaries.values());
+					if (includeHistoric)
+						crossChainOfferSummaries.addAll(cachedInfo.historicSummaries.values());
+				}
 			}
 		}
 

src/main/java/org/qortal/api/websocket/TradePresenceWebSocket.java

@@ -65,11 +65,15 @@ public class TradePresenceWebSocket extends ApiWebSocket implements Listener {
 	@Override
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		final boolean excludeInitialData = queryParams.get("excludeInitialData") != null;
 
-		List<TradePresenceData> tradePresences;
+		List<TradePresenceData> tradePresences = new ArrayList<>();
 
-		synchronized (currentEntries) {
-			tradePresences = List.copyOf(currentEntries.values());
+		// We might need to exclude the initial data from the response
+		if (!excludeInitialData) {
+			synchronized (currentEntries) {
+				tradePresences = List.copyOf(currentEntries.values());
+			}
 		}
 
 		if (!sendTradePresences(session, tradePresences)) {

src/main/java/org/qortal/arbitrary/ArbitraryDataFile.java

@@ -94,14 +94,9 @@ public class ArbitraryDataFile {
         try (FileOutputStream outputStream = new FileOutputStream(outputFile)) {
             outputStream.write(fileContent);
             this.filePath = outputFilePath;
-            // Verify hash
-            if (!this.hash58.equals(this.digest58())) {
-                LOGGER.error("Hash {} does not match file digest {} for signature: {}", this.hash58, this.digest58(), Base58.encode(signature));
-                this.delete();
-                throw new DataException("Data file digest validation failed");
-            }
         } catch (IOException e) {
-            throw new DataException("Unable to write data to file");
+            this.delete();
+            throw new DataException(String.format("Unable to write data with hash %s: %s", this.hash58, e.getMessage()));
         }
     }
 

src/main/java/org/qortal/arbitrary/ArbitraryDataReader.java

@@ -170,6 +170,7 @@ public class ArbitraryDataReader {
             this.validate();
 
         } catch (DataException e) {
+            LOGGER.info("DataException when trying to load QDN resource", e);
             this.deleteWorkingDirectory();
             throw new DataException(e.getMessage());
 
@@ -208,8 +209,13 @@ public class ArbitraryDataReader {
      * serve a cached version of the resource for subsequent requests.
      * @throws IOException
      */
-    private void deleteWorkingDirectory() throws IOException {
-        FilesystemUtils.safeDeleteDirectory(this.workingPath, true);
+    private void deleteWorkingDirectory() {
+        try {
+            FilesystemUtils.safeDeleteDirectory(this.workingPath, true);
+        } catch (IOException e) {
+            // Ignore failures as this isn't an essential step
+            LOGGER.info("Unable to delete working path {}: {}", this.workingPath, e.getMessage());
+        }
     }
 
     private void createUncompressedDirectory() throws DataException {
@@ -408,6 +414,7 @@ public class ArbitraryDataReader {
             this.decryptUsingAlgo("AES/CBC/PKCS5Padding");
 
         } catch (DataException e) {
+            LOGGER.info("Unable to decrypt using specific parameters: {}", e.getMessage());
             // Something went wrong, so fall back to default AES params (necessary for legacy resource support)
             this.decryptUsingAlgo("AES");
 
@@ -420,8 +427,9 @@ public class ArbitraryDataReader {
         byte[] secret = this.secret58 != null ? Base58.decode(this.secret58) : null;
         if (secret != null && secret.length == Transformer.AES256_LENGTH) {
             try {
+                LOGGER.info("Decrypting using algorithm {}...", algorithm);
                 Path unencryptedPath = Paths.get(this.workingPath.toString(), "zipped.zip");
-                SecretKey aesKey = new SecretKeySpec(secret, 0, secret.length, algorithm);
+                SecretKey aesKey = new SecretKeySpec(secret, 0, secret.length, "AES");
                 AES.decryptFile(algorithm, aesKey, this.filePath.toString(), unencryptedPath.toString());
 
                 // Replace filePath pointer with the encrypted file path
@@ -430,7 +438,8 @@ public class ArbitraryDataReader {
 
             } catch (NoSuchAlgorithmException | InvalidAlgorithmParameterException | NoSuchPaddingException
                     | BadPaddingException | IllegalBlockSizeException | IOException | InvalidKeyException e) {
-                throw new DataException(String.format("Unable to decrypt file at path %s: %s", this.filePath, e.getMessage()));
+                LOGGER.info(String.format("Exception when decrypting using algorithm %s", algorithm), e);
+                throw new DataException(String.format("Unable to decrypt file at path %s using algorithm %s: %s", this.filePath, algorithm, e.getMessage()));
             }
         } else {
             // Assume it is unencrypted. This will be the case when we have built a custom path by combining
@@ -477,7 +486,12 @@ public class ArbitraryDataReader {
         // Delete original compressed file
         if (FilesystemUtils.pathInsideDataOrTempPath(this.filePath)) {
             if (Files.exists(this.filePath)) {
-                Files.delete(this.filePath);
+                try {
+                    Files.delete(this.filePath);
+                } catch (IOException e) {
+                    // Ignore failures as this isn't an essential step
+                    LOGGER.info("Unable to delete file at path {}", this.filePath);
+                }
             }
         }
 

src/main/java/org/qortal/arbitrary/ArbitraryDataRenderer.java

@@ -120,7 +120,7 @@ public class ArbitraryDataRenderer {
                 byte[] data = Files.readAllBytes(Paths.get(filePath)); // TODO: limit file size that can be read into memory
                 HTMLParser htmlParser = new HTMLParser(resourceId, inPath, prefix, usePrefix, data);
                 htmlParser.addAdditionalHeaderTags();
-                response.addHeader("Content-Security-Policy", "default-src 'self' 'unsafe-inline' 'unsafe-eval'; media-src 'self' blob:");
+                response.addHeader("Content-Security-Policy", "default-src 'self' 'unsafe-inline' 'unsafe-eval'; media-src 'self' blob:; img-src 'self' data: blob:;");
                 response.setContentType(context.getMimeType(filename));
                 response.setContentLength(htmlParser.getData().length);
                 response.getOutputStream().write(htmlParser.getData());

src/main/java/org/qortal/block/Block.java

@@ -3,9 +3,12 @@ package org.qortal.block;
 import static java.util.Arrays.stream;
 import static java.util.stream.Collectors.toMap;
 
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.math.RoundingMode;
+import java.nio.charset.StandardCharsets;
 import java.text.DecimalFormat;
 import java.text.NumberFormat;
 import java.util.*;
@@ -24,6 +27,7 @@ import org.qortal.block.BlockChain.BlockTimingByHeight;
 import org.qortal.block.BlockChain.AccountLevelShareBin;
 import org.qortal.controller.OnlineAccountsManager;
 import org.qortal.crypto.Crypto;
+import org.qortal.crypto.Qortal25519Extras;
 import org.qortal.data.account.AccountBalanceData;
 import org.qortal.data.account.AccountData;
 import org.qortal.data.account.EligibleQoraHolderData;
@@ -85,7 +89,8 @@ public class Block {
 		ONLINE_ACCOUNT_UNKNOWN(71),
 		ONLINE_ACCOUNT_SIGNATURES_MISSING(72),
 		ONLINE_ACCOUNT_SIGNATURES_MALFORMED(73),
-		ONLINE_ACCOUNT_SIGNATURE_INCORRECT(74);
+		ONLINE_ACCOUNT_SIGNATURE_INCORRECT(74),
+		ONLINE_ACCOUNT_NONCE_INCORRECT(75);
 
 		public final int value;
 
@@ -118,6 +123,8 @@ public class Block {
 
 	/** Remote/imported/loaded AT states */
 	protected List<ATStateData> atStates;
+	/** Remote hash of AT states - in lieu of full AT state data in {@code atStates} */
+	protected byte[] atStatesHash;
 	/** Locally-generated AT states */
 	protected List<ATStateData> ourAtStates;
 	/** Locally-generated AT fees */
@@ -178,8 +185,11 @@ public class Block {
 			if (accountLevel <= 0)
 				return null; // level 0 isn't included in any share bins
 
+			// Select the correct set of share bins based on block height
 			final BlockChain blockChain = BlockChain.getInstance();
-			final AccountLevelShareBin[] shareBinsByLevel = blockChain.getShareBinsByAccountLevel();
+			final AccountLevelShareBin[] shareBinsByLevel = (blockHeight >= blockChain.getSharesByLevelV2Height()) ?
+					blockChain.getShareBinsByAccountLevelV2() : blockChain.getShareBinsByAccountLevelV1();
+
 			if (accountLevel > shareBinsByLevel.length)
 				return null;
 
@@ -192,6 +202,11 @@ public class Block {
 
 		}
 
+		public boolean hasShareBin(AccountLevelShareBin shareBin, int blockHeight) {
+			AccountLevelShareBin ourShareBin = this.getShareBin(blockHeight);
+			return ourShareBin != null && shareBin.id == ourShareBin.id;
+		}
+
 		public long distribute(long accountAmount, Map<String, Long> balanceChanges) {
 			if (this.isRecipientAlsoMinter) {
 				// minter & recipient the same - simpler case
@@ -216,11 +231,10 @@ public class Block {
 			return accountAmount;
 		}
 	}
+
 	/** Always use getExpandedAccounts() to access this, as it's lazy-instantiated. */
 	private List<ExpandedAccount> cachedExpandedAccounts = null;
 
-	/** Opportunistic cache of this block's valid online accounts. Only created by call to isValid(). */
-	private List<OnlineAccountData> cachedValidOnlineAccounts = null;
 	/** Opportunistic cache of this block's valid online reward-shares. Only created by call to isValid(). */
 	private List<RewardShareData> cachedOnlineRewardShares = null;
 
@@ -255,7 +269,7 @@ public class Block {
 	 * Constructs new Block using passed transaction and AT states.
 	 * <p>
 	 * This constructor typically used when receiving a serialized block over the network.
-	 * 
+	 *
 	 * @param repository
 	 * @param blockData
 	 * @param transactions
@@ -281,6 +295,35 @@ public class Block {
 		this.blockData.setTotalFees(totalFees);
 	}
 
+	/**
+	 * Constructs new Block using passed transaction and minimal AT state info.
+	 * <p>
+	 * This constructor typically used when receiving a serialized block over the network.
+	 *
+	 * @param repository
+	 * @param blockData
+	 * @param transactions
+	 * @param atStatesHash
+	 */
+	public Block(Repository repository, BlockData blockData, List<TransactionData> transactions, byte[] atStatesHash) {
+		this(repository, blockData);
+
+		this.transactions = new ArrayList<>();
+
+		long totalFees = 0;
+
+		// We have to sum fees too
+		for (TransactionData transactionData : transactions) {
+			this.transactions.add(Transaction.fromData(repository, transactionData));
+			totalFees += transactionData.getFee();
+		}
+
+		this.atStatesHash = atStatesHash;
+		totalFees += this.blockData.getATFees();
+
+		this.blockData.setTotalFees(totalFees);
+	}
+
 	/**
 	 * Constructs new Block with empty transaction list, using passed minter account.
 	 * 
@@ -313,18 +356,27 @@ public class Block {
 		int version = parentBlock.getNextBlockVersion();
 		byte[] reference = parentBlockData.getSignature();
 
-		// Fetch our list of online accounts
-		List<OnlineAccountData> onlineAccounts = OnlineAccountsManager.getInstance().getOnlineAccounts();
-		if (onlineAccounts.isEmpty()) {
-			LOGGER.error("No online accounts - not even our own?");
+		// Qortal: minter is always a reward-share, so find actual minter and get their effective minting level
+		int minterLevel = Account.getRewardShareEffectiveMintingLevel(repository, minter.getPublicKey());
+		if (minterLevel == 0) {
+			LOGGER.error("Minter effective level returned zero?");
 			return null;
 		}
 
-		// Find newest online accounts timestamp
-		long onlineAccountsTimestamp = 0;
-		for (OnlineAccountData onlineAccountData : onlineAccounts) {
-			if (onlineAccountData.getTimestamp() > onlineAccountsTimestamp)
-				onlineAccountsTimestamp = onlineAccountData.getTimestamp();
+		long timestamp = calcTimestamp(parentBlockData, minter.getPublicKey(), minterLevel);
+		long onlineAccountsTimestamp = OnlineAccountsManager.getCurrentOnlineAccountTimestamp();
+
+		// Fetch our list of online accounts
+		List<OnlineAccountData> onlineAccounts = OnlineAccountsManager.getInstance().getOnlineAccounts(onlineAccountsTimestamp);
+
+		// If mempow is active, remove any legacy accounts that are missing a nonce
+		if (timestamp >= BlockChain.getInstance().getOnlineAccountsMemoryPoWTimestamp()) {
+			onlineAccounts.removeIf(a -> a.getNonce() == null || a.getNonce() < 0);
+		}
+
+		if (onlineAccounts.isEmpty()) {
+			LOGGER.debug("No online accounts - not even our own?");
+			return null;
 		}
 
 		// Load sorted list of reward share public keys into memory, so that the indexes can be obtained.
@@ -335,10 +387,6 @@ public class Block {
 		// Map using index into sorted list of reward-shares as key
 		Map<Integer, OnlineAccountData> indexedOnlineAccounts = new HashMap<>();
 		for (OnlineAccountData onlineAccountData : onlineAccounts) {
-			// Disregard online accounts with different timestamps
-			if (onlineAccountData.getTimestamp() != onlineAccountsTimestamp)
-				continue;
-
 			Integer accountIndex = getRewardShareIndex(onlineAccountData.getPublicKey(), allRewardSharePublicKeys);
 			if (accountIndex == null)
 				// Online account (reward-share) with current timestamp but reward-share cancelled
@@ -355,26 +403,43 @@ public class Block {
 		byte[] encodedOnlineAccounts = BlockTransformer.encodeOnlineAccounts(onlineAccountsSet);
 		int onlineAccountsCount = onlineAccountsSet.size();
 
-		// Concatenate online account timestamp signatures (in correct order)
-		byte[] onlineAccountsSignatures = new byte[onlineAccountsCount * Transformer.SIGNATURE_LENGTH];
-		for (int i = 0; i < onlineAccountsCount; ++i) {
-			Integer accountIndex = accountIndexes.get(i);
-			OnlineAccountData onlineAccountData = indexedOnlineAccounts.get(accountIndex);
-			System.arraycopy(onlineAccountData.getSignature(), 0, onlineAccountsSignatures, i * Transformer.SIGNATURE_LENGTH, Transformer.SIGNATURE_LENGTH);
+		// Collate all signatures
+		Collection<byte[]> signaturesToAggregate = indexedOnlineAccounts.values()
+				.stream()
+				.map(OnlineAccountData::getSignature)
+				.collect(Collectors.toList());
+
+		// Aggregated, single signature
+		byte[] onlineAccountsSignatures = Qortal25519Extras.aggregateSignatures(signaturesToAggregate);
+
+		// Add nonces to the end of the online accounts signatures if mempow is active
+		if (timestamp >= BlockChain.getInstance().getOnlineAccountsMemoryPoWTimestamp()) {
+			try {
+				// Create ordered list of nonce values
+				List<Integer> nonces = new ArrayList<>();
+				for (int i = 0; i < onlineAccountsCount; ++i) {
+					Integer accountIndex = accountIndexes.get(i);
+					OnlineAccountData onlineAccountData = indexedOnlineAccounts.get(accountIndex);
+					nonces.add(onlineAccountData.getNonce());
+				}
+
+				// Encode the nonces to a byte array
+				byte[] encodedNonces = BlockTransformer.encodeOnlineAccountNonces(nonces);
+
+				// Append the encoded nonces to the encoded online account signatures
+				ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+				outputStream.write(onlineAccountsSignatures);
+				outputStream.write(encodedNonces);
+				onlineAccountsSignatures = outputStream.toByteArray();
+			}
+			catch (TransformationException | IOException e) {
+				return null;
+			}
 		}
 
 		byte[] minterSignature = minter.sign(BlockTransformer.getBytesForMinterSignature(parentBlockData,
 				minter.getPublicKey(), encodedOnlineAccounts));
 
-		// Qortal: minter is always a reward-share, so find actual minter and get their effective minting level
-		int minterLevel = Account.getRewardShareEffectiveMintingLevel(repository, minter.getPublicKey());
-		if (minterLevel == 0) {
-			LOGGER.error("Minter effective level returned zero?");
-			return null;
-		}
-
-		long timestamp = calcTimestamp(parentBlockData, minter.getPublicKey(), minterLevel);
-
 		int transactionCount = 0;
 		byte[] transactionsSignature = null;
 		int height = parentBlockData.getHeight() + 1;
@@ -979,49 +1044,68 @@ public class Block {
 		if (this.blockData.getOnlineAccountsSignatures() == null || this.blockData.getOnlineAccountsSignatures().length == 0)
 			return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MISSING;
 
-		if (this.blockData.getOnlineAccountsSignatures().length != onlineRewardShares.size() * Transformer.SIGNATURE_LENGTH)
-			return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MALFORMED;
+		final int signaturesLength = Transformer.SIGNATURE_LENGTH;
+		final int noncesLength = onlineRewardShares.size() * Transformer.INT_LENGTH;
+
+		if (this.blockData.getTimestamp() >= BlockChain.getInstance().getOnlineAccountsMemoryPoWTimestamp()) {
+			// We expect nonces to be appended to the online accounts signatures
+			if (this.blockData.getOnlineAccountsSignatures().length != signaturesLength + noncesLength)
+				return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MALFORMED;
+		} else {
+			if (this.blockData.getOnlineAccountsSignatures().length != signaturesLength)
+				return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MALFORMED;
+		}
 
 		// Check signatures
 		long onlineTimestamp = this.blockData.getOnlineAccountsTimestamp();
 		byte[] onlineTimestampBytes = Longs.toByteArray(onlineTimestamp);
 
-		// If this block is much older than current online timestamp, then there's no point checking current online accounts
-		List<OnlineAccountData> currentOnlineAccounts = onlineTimestamp < NTP.getTime() - OnlineAccountsManager.ONLINE_TIMESTAMP_MODULUS
-				? null
-				: OnlineAccountsManager.getInstance().getOnlineAccounts();
-		List<OnlineAccountData> latestBlocksOnlineAccounts = OnlineAccountsManager.getInstance().getLatestBlocksOnlineAccounts();
+		byte[] encodedOnlineAccountSignatures = this.blockData.getOnlineAccountsSignatures();
 
-		// Extract online accounts' timestamp signatures from block data
-		List<byte[]> onlineAccountsSignatures = BlockTransformer.decodeTimestampSignatures(this.blockData.getOnlineAccountsSignatures());
+		// Split online account signatures into signature(s) + nonces, then validate the nonces
+		if (this.blockData.getTimestamp() >= BlockChain.getInstance().getOnlineAccountsMemoryPoWTimestamp()) {
+			byte[] extractedSignatures = BlockTransformer.extract(encodedOnlineAccountSignatures, 0, signaturesLength);
+			byte[] extractedNonces = BlockTransformer.extract(encodedOnlineAccountSignatures, signaturesLength, onlineRewardShares.size() * Transformer.INT_LENGTH);
+			encodedOnlineAccountSignatures = extractedSignatures;
 
-		// We'll build up a list of online accounts to hand over to Controller if block is added to chain
-		// and this will become latestBlocksOnlineAccounts (above) to reduce CPU load when we process next block...
-		List<OnlineAccountData> ourOnlineAccounts = new ArrayList<>();
+			List<Integer> nonces = BlockTransformer.decodeOnlineAccountNonces(extractedNonces);
 
-		for (int i = 0; i < onlineAccountsSignatures.size(); ++i) {
-			byte[] signature = onlineAccountsSignatures.get(i);
-			byte[] publicKey = onlineRewardShares.get(i).getRewardSharePublicKey();
+			// Build block's view of online accounts (without signatures, as we don't need them here)
+			Set<OnlineAccountData> onlineAccounts = new HashSet<>();
+			for (int i = 0; i < onlineRewardShares.size(); ++i) {
+				Integer nonce = nonces.get(i);
+				byte[] publicKey = onlineRewardShares.get(i).getRewardSharePublicKey();
 
-			OnlineAccountData onlineAccountData = new OnlineAccountData(onlineTimestamp, signature, publicKey);
-			ourOnlineAccounts.add(onlineAccountData);
+				OnlineAccountData onlineAccountData = new OnlineAccountData(onlineTimestamp, null, publicKey, nonce);
+				onlineAccounts.add(onlineAccountData);
+			}
 
-			// If signature is still current then no need to perform Ed25519 verify
-			if (currentOnlineAccounts != null && currentOnlineAccounts.remove(onlineAccountData))
-				// remove() returned true, so online account still current
-				// and one less entry in currentOnlineAccounts to check next time
-				continue;
+			// Remove those already validated & cached by online accounts manager - no need to re-validate them
+			OnlineAccountsManager.getInstance().removeKnown(onlineAccounts, onlineTimestamp);
 
-			// If signature was okay in latest block then no need to perform Ed25519 verify
-			if (latestBlocksOnlineAccounts != null && latestBlocksOnlineAccounts.contains(onlineAccountData))
-				continue;
-
-			if (!Crypto.verify(publicKey, signature, onlineTimestampBytes))
-				return ValidationResult.ONLINE_ACCOUNT_SIGNATURE_INCORRECT;
+			// Validate the rest
+			for (OnlineAccountData onlineAccount : onlineAccounts)
+				if (!OnlineAccountsManager.getInstance().verifyMemoryPoW(onlineAccount, this.blockData.getTimestamp()))
+					return ValidationResult.ONLINE_ACCOUNT_NONCE_INCORRECT;
 		}
 
+		// Extract online accounts' timestamp signatures from block data. Only one signature if aggregated.
+		List<byte[]> onlineAccountsSignatures = BlockTransformer.decodeTimestampSignatures(encodedOnlineAccountSignatures);
+
+		// Aggregate all public keys
+		Collection<byte[]> publicKeys = onlineRewardShares.stream()
+				.map(RewardShareData::getRewardSharePublicKey)
+				.collect(Collectors.toList());
+
+		byte[] aggregatePublicKey = Qortal25519Extras.aggregatePublicKeys(publicKeys);
+
+		byte[] aggregateSignature = onlineAccountsSignatures.get(0);
+
+		// One-step verification of aggregate signature using aggregate public key
+		if (!Qortal25519Extras.verifyAggregated(aggregatePublicKey, aggregateSignature, onlineTimestampBytes))
+			return ValidationResult.ONLINE_ACCOUNT_SIGNATURE_INCORRECT;
+
 		// All online accounts valid, so save our list of online accounts for potential later use
-		this.cachedValidOnlineAccounts = ourOnlineAccounts;
 		this.cachedOnlineRewardShares = onlineRewardShares;
 
 		return ValidationResult.OK;
@@ -1168,6 +1252,7 @@ public class Block {
 				}
 			}
 		} catch (DataException e) {
+			LOGGER.info("DataException during transaction validation", e);
 			return ValidationResult.TRANSACTION_INVALID;
 		} finally {
 			// Rollback repository changes made by test-processing transactions above
@@ -1194,7 +1279,7 @@ public class Block {
 	 */
 	private ValidationResult areAtsValid() throws DataException {
 		// Locally generated AT states should be valid so no need to re-execute them
-		if (this.ourAtStates == this.getATStates()) // Note object reference compare
+		if (this.ourAtStates != null && this.ourAtStates == this.atStates) // Note object reference compare
 			return ValidationResult.OK;
 
 		// Generate local AT states for comparison
@@ -1208,8 +1293,33 @@ public class Block {
 		if (this.ourAtFees != this.blockData.getATFees())
 			return ValidationResult.AT_STATES_MISMATCH;
 
-		// Note: this.atStates fully loaded thanks to this.getATStates() call above
-		for (int s = 0; s < this.atStates.size(); ++s) {
+		// If we have a single AT states hash then compare that in preference
+		if (this.atStatesHash != null) {
+			int atBytesLength = blockData.getATCount() * BlockTransformer.AT_ENTRY_LENGTH;
+			ByteArrayOutputStream atHashBytes = new ByteArrayOutputStream(atBytesLength);
+
+			try {
+				for (ATStateData atStateData : this.ourAtStates) {
+					atHashBytes.write(atStateData.getATAddress().getBytes(StandardCharsets.UTF_8));
+					atHashBytes.write(atStateData.getStateHash());
+					atHashBytes.write(Longs.toByteArray(atStateData.getFees()));
+				}
+			} catch (IOException e) {
+				throw new DataException("Couldn't validate AT states hash due to serialization issue?", e);
+			}
+
+			byte[] ourAtStatesHash = Crypto.digest(atHashBytes.toByteArray());
+			if (!Arrays.equals(ourAtStatesHash, this.atStatesHash))
+				return ValidationResult.AT_STATES_MISMATCH;
+
+			// Use our AT state data from now on
+			this.atStates = this.ourAtStates;
+			return ValidationResult.OK;
+		}
+
+		// Note: this.atStates fully loaded thanks to this.getATStates() call:
+		this.getATStates();
+		for (int s = 0; s < this.ourAtStates.size(); ++s) {
 			ATStateData ourAtState = this.ourAtStates.get(s);
 			ATStateData theirAtState = this.atStates.get(s);
 
@@ -1367,9 +1477,6 @@ public class Block {
 
 		postBlockTidy();
 
-		// Give Controller our cached, valid online accounts data (if any) to help reduce CPU load for next block
-		OnlineAccountsManager.getInstance().pushLatestBlocksOnlineAccounts(this.cachedValidOnlineAccounts);
-
 		// Log some debugging info relating to the block weight calculation
 		this.logDebugInfo();
 	}
@@ -1585,9 +1692,6 @@ public class Block {
 		this.blockData.setHeight(null);
 
 		postBlockTidy();
-
-		// Remove any cached, valid online accounts data from Controller
-		OnlineAccountsManager.getInstance().popLatestBlocksOnlineAccounts();
 	}
 
 	protected void orphanTransactionsFromBlock() throws DataException {
@@ -1824,13 +1928,72 @@ public class Block {
 		final List<ExpandedAccount> onlineFounderAccounts = expandedAccounts.stream().filter(expandedAccount -> expandedAccount.isMinterFounder).collect(Collectors.toList());
 		final boolean haveFounders = !onlineFounderAccounts.isEmpty();
 
+		// Select the correct set of share bins based on block height
+		List<AccountLevelShareBin> accountLevelShareBinsForBlock = (this.blockData.getHeight() >= BlockChain.getInstance().getSharesByLevelV2Height()) ?
+				BlockChain.getInstance().getAccountLevelShareBinsV2() : BlockChain.getInstance().getAccountLevelShareBinsV1();
+
 		// Determine reward candidates based on account level
-		List<AccountLevelShareBin> accountLevelShareBins = BlockChain.getInstance().getAccountLevelShareBins();
-		for (int binIndex = 0; binIndex < accountLevelShareBins.size(); ++binIndex) {
-			// Find all accounts in share bin. getShareBin() returns null for minter accounts that are also founders, so they are effectively filtered out.
+		// This needs a deep copy, so the shares can be modified when tiers aren't activated yet
+		List<AccountLevelShareBin> accountLevelShareBins = new ArrayList<>();
+		for (AccountLevelShareBin accountLevelShareBin : accountLevelShareBinsForBlock) {
+			accountLevelShareBins.add((AccountLevelShareBin) accountLevelShareBin.clone());
+		}
+
+		Map<Integer, List<ExpandedAccount>> accountsForShareBin = new HashMap<>();
+
+		// We might need to combine some share bins if they haven't reached the minimum number of minters yet
+		for (int binIndex = accountLevelShareBins.size()-1; binIndex >= 0; --binIndex) {
 			AccountLevelShareBin accountLevelShareBin = accountLevelShareBins.get(binIndex);
-			// Object reference compare is OK as all references are read-only from blockchain config.
-			List<ExpandedAccount> binnedAccounts = expandedAccounts.stream().filter(accountInfo -> accountInfo.getShareBin(this.blockData.getHeight()) == accountLevelShareBin).collect(Collectors.toList());
+
+			// Find all accounts in share bin. getShareBin() returns null for minter accounts that are also founders, so they are effectively filtered out.
+			List<ExpandedAccount> binnedAccounts = expandedAccounts.stream().filter(accountInfo -> accountInfo.hasShareBin(accountLevelShareBin, this.blockData.getHeight())).collect(Collectors.toList());
+			// Add any accounts that have been moved down from a higher tier
+			List<ExpandedAccount> existingBinnedAccounts = accountsForShareBin.get(binIndex);
+			if (existingBinnedAccounts != null)
+				binnedAccounts.addAll(existingBinnedAccounts);
+
+			// Logic below may only apply to higher levels, and only for share bins with a specific range of online accounts
+			if (accountLevelShareBin.levels.get(0) < BlockChain.getInstance().getShareBinActivationMinLevel() ||
+					binnedAccounts.isEmpty() || binnedAccounts.size() >= BlockChain.getInstance().getMinAccountsToActivateShareBin()) {
+				// Add all accounts for this share bin to the accountsForShareBin list
+				accountsForShareBin.put(binIndex, binnedAccounts);
+				continue;
+			}
+
+			// Share bin contains more than one, but less than the minimum number of minters. We treat this share bin
+			// as not activated yet. In these cases, the rewards and minters are combined and paid out to the previous
+			// share bin, to prevent a single or handful of accounts receiving the entire rewards for a share bin.
+			//
+			// Example:
+			//
+			// - Share bin for levels 5 and 6 has 100 minters
+			// - Share bin for levels 7 and 8 has 10 minters
+			//
+			// This is below the minimum of 30, so share bins are reconstructed as follows:
+			//
+			// - Share bin for levels 5 and 6 now contains 110 minters
+			// - Share bin for levels 7 and 8 now contains 0 minters
+			// - Share bin for levels 5 and 6 now pays out rewards for levels 5, 6, 7, and 8
+			// - Share bin for levels 7 and 8 pays zero rewards
+			//
+			// This process is iterative, so will combine several tiers if needed.
+
+			// Designate this share bin as empty
+			accountsForShareBin.put(binIndex, new ArrayList<>());
+
+			// Move the accounts originally intended for this share bin to the previous one
+			accountsForShareBin.put(binIndex - 1, binnedAccounts);
+
+			// Move the block reward from this share bin to the previous one
+			AccountLevelShareBin previousShareBin = accountLevelShareBins.get(binIndex - 1);
+			previousShareBin.share += accountLevelShareBin.share;
+			accountLevelShareBin.share = 0L;
+		}
+
+		// Now loop through (potentially modified) share bins and determine the reward candidates
+		for (int binIndex = 0; binIndex < accountLevelShareBins.size(); ++binIndex) {
+			AccountLevelShareBin accountLevelShareBin = accountLevelShareBins.get(binIndex);
+			List<ExpandedAccount> binnedAccounts = accountsForShareBin.get(binIndex);
 
 			// No online accounts in this bin? Skip to next one
 			if (binnedAccounts.isEmpty())
@@ -1848,7 +2011,7 @@ public class Block {
 		// Fetch list of legacy QORA holders who haven't reached their cap of QORT reward.
 		List<EligibleQoraHolderData> qoraHolders = this.repository.getAccountRepository().getEligibleLegacyQoraHolders(isProcessingNotOrphaning ? null : this.blockData.getHeight());
 		final boolean haveQoraHolders = !qoraHolders.isEmpty();
-		final long qoraHoldersShare = BlockChain.getInstance().getQoraHoldersShare();
+		final long qoraHoldersShare = BlockChain.getInstance().getQoraHoldersShareAtHeight(this.blockData.getHeight());
 
 		// Perform account-level-based reward scaling if appropriate
 		if (!haveFounders) {

src/main/java/org/qortal/block/BlockChain.java

@@ -68,8 +68,12 @@ public class BlockChain {
 		atFindNextTransactionFix,
 		newBlockSigHeight,
 		shareBinFix,
+		sharesByLevelV2Height,
+		rewardShareLimitTimestamp,
 		calcChainWeightTimestamp,
-		transactionV5Timestamp;
+		transactionV5Timestamp,
+		transactionV6Timestamp,
+		disableReferenceTimestamp;
 	}
 
 	// Custom transaction fees
@@ -100,23 +104,48 @@ public class BlockChain {
 	private List<RewardByHeight> rewardsByHeight;
 
 	/** Share of block reward/fees by account level */
-	public static class AccountLevelShareBin {
+	public static class AccountLevelShareBin implements Cloneable {
+		public int id;
 		public List<Integer> levels;
 		@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
 		public long share;
-	}
-	private List<AccountLevelShareBin> sharesByLevel;
-	/** Generated lookup of share-bin by account level */
-	private AccountLevelShareBin[] shareBinsByLevel;
 
-	/** Share of block reward/fees to legacy QORA coin holders */
-	@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
-	private Long qoraHoldersShare;
+		public Object clone() {
+			AccountLevelShareBin shareBinCopy = new AccountLevelShareBin();
+			List<Integer> levelsCopy = new ArrayList<>();
+			for (Integer level : this.levels) {
+				levelsCopy.add(level);
+			}
+			shareBinCopy.id = this.id;
+			shareBinCopy.levels = levelsCopy;
+			shareBinCopy.share = this.share;
+			return shareBinCopy;
+		}
+	}
+	private List<AccountLevelShareBin> sharesByLevelV1;
+	private List<AccountLevelShareBin> sharesByLevelV2;
+	/** Generated lookup of share-bin by account level */
+	private AccountLevelShareBin[] shareBinsByLevelV1;
+	private AccountLevelShareBin[] shareBinsByLevelV2;
+
+	/** Share of block reward/fees to legacy QORA coin holders, by block height */
+	public static class ShareByHeight {
+		public int height;
+		@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
+		public long share;
+	}
+	private List<ShareByHeight> qoraHoldersShareByHeight;
 
 	/** How many legacy QORA per 1 QORT of block reward. */
 	@XmlJavaTypeAdapter(value = org.qortal.api.AmountTypeAdapter.class)
 	private Long qoraPerQortReward;
 
+	/** Minimum number of accounts before a share bin is considered activated */
+	private int minAccountsToActivateShareBin;
+
+	/** Min level at which share bin activation takes place; lower levels allow less than minAccountsPerShareBin */
+	private int shareBinActivationMinLevel;
+
 	/**
 	 * Number of minted blocks required to reach next level from previous.
 	 * <p>
@@ -154,7 +183,7 @@ public class BlockChain {
 	private int minAccountLevelToMint;
 	private int minAccountLevelForBlockSubmissions;
 	private int minAccountLevelToRewardShare;
-	private int maxRewardSharesPerMintingAccount;
+	private int maxRewardSharesPerFounderMintingAccount;
 	private int founderEffectiveMintingLevel;
 
 	/** Minimum time to retain online account signatures (ms) for block validity checks. */
@@ -162,6 +191,21 @@ public class BlockChain {
 	/** Maximum time to retain online account signatures (ms) for block validity checks, to allow for clock variance. */
 	private long onlineAccountSignaturesMaxLifetime;
 
+	/** Feature trigger timestamp for ONLINE_ACCOUNTS_MODULUS time interval increase. Can't use
+	 * featureTriggers because unit tests need to set this value via Reflection. */
+	private long onlineAccountsModulusV2Timestamp;
+
+	/** Feature trigger timestamp for online accounts mempow verification. Can't use featureTriggers
+	 * because unit tests need to set this value via Reflection. */
+	private long onlineAccountsMemoryPoWTimestamp;
+
+	/** Max reward shares by block height */
+	public static class MaxRewardSharesByTimestamp {
+		public long timestamp;
+		public int maxShares;
+	}
+	private List<MaxRewardSharesByTimestamp> maxRewardSharesByTimestamp;
+
 	/** Settings relating to CIYAM AT feature. */
 	public static class CiyamAtSettings {
 		/** Fee per step/op-code executed. */
@@ -310,6 +354,15 @@ public class BlockChain {
 		return this.maxBlockSize;
 	}
 
+	// Online accounts
+	public long getOnlineAccountsModulusV2Timestamp() {
+		return this.onlineAccountsModulusV2Timestamp;
+	}
+
+	public long getOnlineAccountsMemoryPoWTimestamp() {
+		return this.onlineAccountsMemoryPoWTimestamp;
+	}
+
 	/** Returns true if approval-needing transaction types require a txGroupId other than NO_GROUP. */
 	public boolean getRequireGroupForApproval() {
 		return this.requireGroupForApproval;
@@ -327,12 +380,20 @@ public class BlockChain {
 		return this.rewardsByHeight;
 	}
 
-	public List<AccountLevelShareBin> getAccountLevelShareBins() {
-		return this.sharesByLevel;
+	public List<AccountLevelShareBin> getAccountLevelShareBinsV1() {
+		return this.sharesByLevelV1;
 	}
 
-	public AccountLevelShareBin[] getShareBinsByAccountLevel() {
-		return this.shareBinsByLevel;
+	public List<AccountLevelShareBin> getAccountLevelShareBinsV2() {
+		return this.sharesByLevelV2;
+	}
+
+	public AccountLevelShareBin[] getShareBinsByAccountLevelV1() {
+		return this.shareBinsByLevelV1;
+	}
+
+	public AccountLevelShareBin[] getShareBinsByAccountLevelV2() {
+		return this.shareBinsByLevelV2;
 	}
 
 	public List<Integer> getBlocksNeededByLevel() {
@@ -343,14 +404,18 @@ public class BlockChain {
 		return this.cumulativeBlocksByLevel;
 	}
 
-	public long getQoraHoldersShare() {
-		return this.qoraHoldersShare;
-	}
-
 	public long getQoraPerQortReward() {
 		return this.qoraPerQortReward;
 	}
 
+	public int getMinAccountsToActivateShareBin() {
+		return this.minAccountsToActivateShareBin;
+	}
+
+	public int getShareBinActivationMinLevel() {
+		return this.shareBinActivationMinLevel;
+	}
+
 	public int getMinAccountLevelToMint() {
 		return this.minAccountLevelToMint;
 	}
@@ -363,8 +428,8 @@ public class BlockChain {
 		return this.minAccountLevelToRewardShare;
 	}
 
-	public int getMaxRewardSharesPerMintingAccount() {
-		return this.maxRewardSharesPerMintingAccount;
+	public int getMaxRewardSharesPerFounderMintingAccount() {
+		return this.maxRewardSharesPerFounderMintingAccount;
 	}
 
 	public int getFounderEffectiveMintingLevel() {
@@ -397,6 +462,14 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.shareBinFix.name()).intValue();
 	}
 
+	public int getSharesByLevelV2Height() {
+		return this.featureTriggers.get(FeatureTrigger.sharesByLevelV2Height.name()).intValue();
+	}
+
+	public long getRewardShareLimitTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.rewardShareLimitTimestamp.name()).longValue();
+	}
+
 	public long getCalcChainWeightTimestamp() {
 		return this.featureTriggers.get(FeatureTrigger.calcChainWeightTimestamp.name()).longValue();
 	}
@@ -405,6 +478,15 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.transactionV5Timestamp.name()).longValue();
 	}
 
+	public long getTransactionV6Timestamp() {
+		return this.featureTriggers.get(FeatureTrigger.transactionV6Timestamp.name()).longValue();
+	}
+
+	public long getDisableReferenceTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.disableReferenceTimestamp.name()).longValue();
+	}
+
+
 	// More complex getters for aspects that change by height or timestamp
 
 	public long getRewardAtHeight(int ourHeight) {
@@ -425,15 +507,31 @@ public class BlockChain {
 	}
 
 	public long getNameRegistrationUnitFeeAtTimestamp(long ourTimestamp) {
-		// Scan through for reward at our height
-		for (int i = 0; i < nameRegistrationUnitFees.size(); ++i)
-			if (ourTimestamp >= nameRegistrationUnitFees.get(i).timestamp)
+		for (int i = nameRegistrationUnitFees.size() - 1; i >= 0; --i)
+			if (nameRegistrationUnitFees.get(i).timestamp <= ourTimestamp)
 				return nameRegistrationUnitFees.get(i).fee;
 
 		// Default to system-wide unit fee
 		return this.getUnitFee();
 	}
 
+	public int getMaxRewardSharesAtTimestamp(long ourTimestamp) {
+		for (int i = maxRewardSharesByTimestamp.size() - 1; i >= 0; --i)
+			if (maxRewardSharesByTimestamp.get(i).timestamp <= ourTimestamp)
+				return maxRewardSharesByTimestamp.get(i).maxShares;
+
+		return 0;
+	}
+
+	public long getQoraHoldersShareAtHeight(int ourHeight) {
+		// Scan through for QORA share at our height
+		for (int i = qoraHoldersShareByHeight.size() - 1; i >= 0; --i)
+			if (qoraHoldersShareByHeight.get(i).height <= ourHeight)
+				return qoraHoldersShareByHeight.get(i).share;
+
+		return 0;
+	}
+
 	/** Validate blockchain config read from JSON */
 	private void validateConfig() {
 		if (this.genesisInfo == null)
@@ -442,11 +540,14 @@ public class BlockChain {
 		if (this.rewardsByHeight == null)
 			Settings.throwValidationError("No \"rewardsByHeight\" entry found in blockchain config");
 
-		if (this.sharesByLevel == null)
-			Settings.throwValidationError("No \"sharesByLevel\" entry found in blockchain config");
+		if (this.sharesByLevelV1 == null)
+			Settings.throwValidationError("No \"sharesByLevelV1\" entry found in blockchain config");
 
-		if (this.qoraHoldersShare == null)
-			Settings.throwValidationError("No \"qoraHoldersShare\" entry found in blockchain config");
+		if (this.sharesByLevelV2 == null)
+			Settings.throwValidationError("No \"sharesByLevelV2\" entry found in blockchain config");
+
+		if (this.qoraHoldersShareByHeight == null)
+			Settings.throwValidationError("No \"qoraHoldersShareByHeight\" entry found in blockchain config");
 
 		if (this.qoraPerQortReward == null)
 			Settings.throwValidationError("No \"qoraPerQortReward\" entry found in blockchain config");
@@ -483,13 +584,22 @@ public class BlockChain {
 			if (!this.featureTriggers.containsKey(featureTrigger.name()))
 				Settings.throwValidationError(String.format("Missing feature trigger \"%s\" in blockchain config", featureTrigger.name()));
 
-		// Check block reward share bounds
-		long totalShare = this.qoraHoldersShare;
+		// Check block reward share bounds (V1)
+		long totalShareV1 = this.qoraHoldersShareByHeight.get(0).share;
 		// Add share percents for account-level-based rewards
-		for (AccountLevelShareBin accountLevelShareBin : this.sharesByLevel)
-			totalShare += accountLevelShareBin.share;
+		for (AccountLevelShareBin accountLevelShareBin : this.sharesByLevelV1)
+			totalShareV1 += accountLevelShareBin.share;
 
-		if (totalShare < 0 || totalShare > 1_00000000L)
+		if (totalShareV1 < 0 || totalShareV1 > 1_00000000L)
+			Settings.throwValidationError("Total non-founder share out of bounds (0<x<1e8)");
+
+		// Check block reward share bounds (V2)
+		long totalShareV2 = this.qoraHoldersShareByHeight.get(1).share;
+		// Add share percents for account-level-based rewards
+		for (AccountLevelShareBin accountLevelShareBin : this.sharesByLevelV2)
+			totalShareV2 += accountLevelShareBin.share;
+
+		if (totalShareV2 < 0 || totalShareV2 > 1_00000000L)
 			Settings.throwValidationError("Total non-founder share out of bounds (0<x<1e8)");
 	}
 
@@ -505,23 +615,34 @@ public class BlockChain {
 				cumulativeBlocks += this.blocksNeededByLevel.get(level);
 		}
 
-		// Generate lookup-array for account-level share bins
-		AccountLevelShareBin lastAccountLevelShareBin = this.sharesByLevel.get(this.sharesByLevel.size() - 1);
-		final int lastLevel = lastAccountLevelShareBin.levels.get(lastAccountLevelShareBin.levels.size() - 1);
-		this.shareBinsByLevel = new AccountLevelShareBin[lastLevel];
-
-		for (AccountLevelShareBin accountLevelShareBin : this.sharesByLevel)
+		// Generate lookup-array for account-level share bins (V1)
+		AccountLevelShareBin lastAccountLevelShareBinV1 = this.sharesByLevelV1.get(this.sharesByLevelV1.size() - 1);
+		final int lastLevelV1 = lastAccountLevelShareBinV1.levels.get(lastAccountLevelShareBinV1.levels.size() - 1);
+		this.shareBinsByLevelV1 = new AccountLevelShareBin[lastLevelV1];
+		for (AccountLevelShareBin accountLevelShareBin : this.sharesByLevelV1)
 			for (int level : accountLevelShareBin.levels)
 				// level 1 stored at index 0, level 2 stored at index 1, etc.
 				// level 0 not allowed
-				this.shareBinsByLevel[level - 1] = accountLevelShareBin;
+				this.shareBinsByLevelV1[level - 1] = accountLevelShareBin;
+
+		// Generate lookup-array for account-level share bins (V2)
+		AccountLevelShareBin lastAccountLevelShareBinV2 = this.sharesByLevelV2.get(this.sharesByLevelV2.size() - 1);
+		final int lastLevelV2 = lastAccountLevelShareBinV2.levels.get(lastAccountLevelShareBinV2.levels.size() - 1);
+		this.shareBinsByLevelV2 = new AccountLevelShareBin[lastLevelV2];
+		for (AccountLevelShareBin accountLevelShareBin : this.sharesByLevelV2)
+			for (int level : accountLevelShareBin.levels)
+				// level 1 stored at index 0, level 2 stored at index 1, etc.
+				// level 0 not allowed
+				this.shareBinsByLevelV2[level - 1] = accountLevelShareBin;
 
 		// Convert collections to unmodifiable form
 		this.rewardsByHeight = Collections.unmodifiableList(this.rewardsByHeight);
-		this.sharesByLevel = Collections.unmodifiableList(this.sharesByLevel);
+		this.sharesByLevelV1 = Collections.unmodifiableList(this.sharesByLevelV1);
+		this.sharesByLevelV2 = Collections.unmodifiableList(this.sharesByLevelV2);
 		this.blocksNeededByLevel = Collections.unmodifiableList(this.blocksNeededByLevel);
 		this.cumulativeBlocksByLevel = Collections.unmodifiableList(this.cumulativeBlocksByLevel);
 		this.blockTimingsByHeight = Collections.unmodifiableList(this.blockTimingsByHeight);
+		this.qoraHoldersShareByHeight = Collections.unmodifiableList(this.qoraHoldersShareByHeight);
 	}
 
 	/**

src/main/java/org/qortal/controller/AutoUpdate.java

@@ -15,6 +15,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.TimeoutException;
+import java.util.stream.Collectors;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -40,6 +41,7 @@ public class AutoUpdate extends Thread {
 
 	public static final String JAR_FILENAME = "qortal.jar";
 	public static final String NEW_JAR_FILENAME = "new-" + JAR_FILENAME;
+	public static final String AGENTLIB_JVM_HOLDER_ARG = "-DQORTAL_agentlib=";
 
 	private static final Logger LOGGER = LogManager.getLogger(AutoUpdate.class);
 	private static final long CHECK_INTERVAL = 20 * 60 * 1000L; // ms
@@ -243,6 +245,11 @@ public class AutoUpdate extends Thread {
 			// JVM arguments
 			javaCmd.addAll(ManagementFactory.getRuntimeMXBean().getInputArguments());
 
+			// Disable, but retain, any -agentlib JVM arg as sub-process might fail if it tries to reuse same port
+			javaCmd = javaCmd.stream()
+					.map(arg -> arg.replace("-agentlib", AGENTLIB_JVM_HOLDER_ARG))
+					.collect(Collectors.toList());
+
 			// Remove JNI options as they won't be supported by command-line 'java'
 			// These are typically added by the AdvancedInstaller Java launcher EXE
 			javaCmd.removeAll(Arrays.asList("abort", "exit", "vfprintf"));
@@ -261,10 +268,19 @@ public class AutoUpdate extends Thread {
 					Translator.INSTANCE.translate("SysTray", "APPLYING_UPDATE_AND_RESTARTING"),
 					MessageType.INFO);
 
-			new ProcessBuilder(javaCmd).start();
+			ProcessBuilder processBuilder = new ProcessBuilder(javaCmd);
+
+			// New process will inherit our stdout and stderr
+			processBuilder.redirectOutput(ProcessBuilder.Redirect.INHERIT);
+			processBuilder.redirectError(ProcessBuilder.Redirect.INHERIT);
+
+			Process process = processBuilder.start();
+
+			// Nothing to pipe to new process, so close output stream (process's stdin)
+			process.getOutputStream().close();
 
 			return true; // applying update OK
-		} catch (IOException e) {
+		} catch (Exception e) {
 			LOGGER.error(String.format("Failed to apply update: %s", e.getMessage()));
 
 			try {

src/main/java/org/qortal/controller/BlockMinter.java

@@ -26,6 +26,9 @@ import org.qortal.data.block.CommonBlockData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.network.Network;
 import org.qortal.network.Peer;
+import org.qortal.network.message.BlockSummariesV2Message;
+import org.qortal.network.message.HeightV2Message;
+import org.qortal.network.message.Message;
 import org.qortal.repository.BlockRepository;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
@@ -61,8 +64,12 @@ public class BlockMinter extends Thread {
 	public void run() {
 		Thread.currentThread().setName("BlockMinter");
 
-		try (final Repository repository = RepositoryManager.getRepository()) {
-			if (Settings.getInstance().getWipeUnconfirmedOnStart()) {
+		if (Settings.getInstance().isLite()) {
+			// Lite nodes do not mint
+			return;
+		}
+		if (Settings.getInstance().getWipeUnconfirmedOnStart()) {
+			try (final Repository repository = RepositoryManager.getRepository()) {
 				// Wipe existing unconfirmed transactions
 				List<TransactionData> unconfirmedTransactions = repository.getTransactionRepository().getUnconfirmedTransactions();
 
@@ -72,356 +79,373 @@ public class BlockMinter extends Thread {
 				}
 
 				repository.saveChanges();
+			} catch (DataException e) {
+				LOGGER.warn("Repository issue trying to wipe unconfirmed transactions on start-up: {}", e.getMessage());
+				// Fall-through to normal behaviour in case we can recover
 			}
+		}
 
+		BlockData previousBlockData = null;
+
+		// Vars to keep track of blocks that were skipped due to chain weight
+		byte[] parentSignatureForLastLowWeightBlock = null;
+		Long timeOfLastLowWeightBlock = null;
+
+		List<Block> newBlocks = new ArrayList<>();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
 			// Going to need this a lot...
 			BlockRepository blockRepository = repository.getBlockRepository();
-			BlockData previousBlockData = null;
-
-			// Vars to keep track of blocks that were skipped due to chain weight
-			byte[] parentSignatureForLastLowWeightBlock = null;
-			Long timeOfLastLowWeightBlock = null;
-
-			List<Block> newBlocks = new ArrayList<>();
 
 			// Flags for tracking change in whether minting is possible,
 			// so we can notify Controller, and further update SysTray, etc.
 			boolean isMintingPossible = false;
 			boolean wasMintingPossible = isMintingPossible;
 			while (running) {
-				repository.discardChanges(); // Free repository locks, if any
-
 				if (isMintingPossible != wasMintingPossible)
 					Controller.getInstance().onMintingPossibleChange(isMintingPossible);
 
 				wasMintingPossible = isMintingPossible;
 
-				// Sleep for a while
-				Thread.sleep(1000);
-
-				isMintingPossible = false;
-
-				final Long now = NTP.getTime();
-				if (now == null)
-					continue;
-
-				final Long minLatestBlockTimestamp = Controller.getMinimumLatestBlockTimestamp();
-				if (minLatestBlockTimestamp == null)
-					continue;
-
-				// No online accounts? (e.g. during startup)
-				if (OnlineAccountsManager.getInstance().getOnlineAccounts().isEmpty())
-					continue;
-
-				List<MintingAccountData> mintingAccountsData = repository.getAccountRepository().getMintingAccounts();
-				// No minting accounts?
-				if (mintingAccountsData.isEmpty())
-					continue;
-
-				// Disregard minting accounts that are no longer valid, e.g. by transfer/loss of founder flag or account level
-				// Note that minting accounts are actually reward-shares in Qortal
-				Iterator<MintingAccountData> madi = mintingAccountsData.iterator();
-				while (madi.hasNext()) {
-					MintingAccountData mintingAccountData = madi.next();
-
-					RewardShareData rewardShareData = repository.getAccountRepository().getRewardShare(mintingAccountData.getPublicKey());
-					if (rewardShareData == null) {
-						// Reward-share doesn't exist - probably cancelled but not yet removed from node's list of minting accounts
-						madi.remove();
-						continue;
-					}
-
-					Account mintingAccount = new Account(repository, rewardShareData.getMinter());
-					if (!mintingAccount.canMint()) {
-						// Minting-account component of reward-share can no longer mint - disregard
-						madi.remove();
-						continue;
-					}
-
-					// Optional (non-validated) prevention of block submissions below a defined level.
-					// This is an unvalidated version of Blockchain.minAccountLevelToMint
-					// and exists only to reduce block candidates by default.
-					int level = mintingAccount.getEffectiveMintingLevel();
-					if (level < BlockChain.getInstance().getMinAccountLevelForBlockSubmissions()) {
-						madi.remove();
-						continue;
-					}
-				}
-
-				// Needs a mutable copy of the unmodifiableList
-				List<Peer> peers = new ArrayList<>(Network.getInstance().getImmutableHandshakedPeers());
-				BlockData lastBlockData = blockRepository.getLastBlock();
-
-				// Disregard peers that have "misbehaved" recently
-				peers.removeIf(Controller.hasMisbehaved);
-
-				// Disregard peers that don't have a recent block, but only if we're not in recovery mode.
-				// In that mode, we want to allow minting on top of older blocks, to recover stalled networks.
-				if (Synchronizer.getInstance().getRecoveryMode() == false)
-					peers.removeIf(Controller.hasNoRecentBlock);
-
-				// Don't mint if we don't have enough up-to-date peers as where would the transactions/consensus come from?
-				if (peers.size() < Settings.getInstance().getMinBlockchainPeers())
-					continue;
-
-				// If we are stuck on an invalid block, we should allow an alternative to be minted
-				boolean recoverInvalidBlock = false;
-				if (Synchronizer.getInstance().timeInvalidBlockLastReceived != null) {
-					// We've had at least one invalid block
-					long timeSinceLastValidBlock = NTP.getTime() - Synchronizer.getInstance().timeValidBlockLastReceived;
-					long timeSinceLastInvalidBlock = NTP.getTime() - Synchronizer.getInstance().timeInvalidBlockLastReceived;
-					if (timeSinceLastValidBlock > INVALID_BLOCK_RECOVERY_TIMEOUT) {
-						if (timeSinceLastInvalidBlock < INVALID_BLOCK_RECOVERY_TIMEOUT) {
-							// Last valid block was more than 10 mins ago, but we've had an invalid block since then
-							// Assume that the chain has stalled because there is no alternative valid candidate
-							// Enter recovery mode to allow alternative, valid candidates to be minted
-							recoverInvalidBlock = true;
-						}
-					}
-				}
-
-				// If our latest block isn't recent then we need to synchronize instead of minting, unless we're in recovery mode.
-				if (!peers.isEmpty() && lastBlockData.getTimestamp() < minLatestBlockTimestamp)
-					if (Synchronizer.getInstance().getRecoveryMode() == false && recoverInvalidBlock == false)
-						continue;
-
-				// There are enough peers with a recent block and our latest block is recent
-				// so go ahead and mint a block if possible.
-				isMintingPossible = true;
-
-				// Check blockchain hasn't changed
-				if (previousBlockData == null || !Arrays.equals(previousBlockData.getSignature(), lastBlockData.getSignature())) {
-					previousBlockData = lastBlockData;
-					newBlocks.clear();
-
-					// Reduce log timeout
-					logTimeout = 10 * 1000L;
-
-					// Last low weight block is no longer valid
-					parentSignatureForLastLowWeightBlock = null;
-				}
-
-				// Discard accounts we have already built blocks with
-				mintingAccountsData.removeIf(mintingAccountData -> newBlocks.stream().anyMatch(newBlock -> Arrays.equals(newBlock.getBlockData().getMinterPublicKey(), mintingAccountData.getPublicKey())));
-
-				// Do we need to build any potential new blocks?
-				List<PrivateKeyAccount> newBlocksMintingAccounts = mintingAccountsData.stream().map(accountData -> new PrivateKeyAccount(repository, accountData.getPrivateKey())).collect(Collectors.toList());
-
-				// We might need to sit the next block out, if one of our minting accounts signed the previous one
-				final byte[] previousBlockMinter = previousBlockData.getMinterPublicKey();
-				final boolean mintedLastBlock = mintingAccountsData.stream().anyMatch(mintingAccount -> Arrays.equals(mintingAccount.getPublicKey(), previousBlockMinter));
-				if (mintedLastBlock) {
-					LOGGER.trace(String.format("One of our keys signed the last block, so we won't sign the next one"));
-					continue;
-				}
-
-				if (parentSignatureForLastLowWeightBlock != null) {
-					// The last iteration found a higher weight block in the network, so sleep for a while
-					// to allow is to sync the higher weight chain. We are sleeping here rather than when
-					// detected as we don't want to hold the blockchain lock open.
-					LOGGER.info("Sleeping for 10 seconds...");
-					Thread.sleep(10 * 1000L);
-				}
-
-				for (PrivateKeyAccount mintingAccount : newBlocksMintingAccounts) {
-					// First block does the AT heavy-lifting
-					if (newBlocks.isEmpty()) {
-						Block newBlock = Block.mint(repository, previousBlockData, mintingAccount);
-						if (newBlock == null) {
-							// For some reason we can't mint right now
-							moderatedLog(() -> LOGGER.error("Couldn't build a to-be-minted block"));
-							continue;
-						}
-
-						newBlocks.add(newBlock);
-					} else {
-						// The blocks for other minters require less effort...
-						Block newBlock = newBlocks.get(0).remint(mintingAccount);
-						if (newBlock == null) {
-							// For some reason we can't mint right now
-							moderatedLog(() -> LOGGER.error("Couldn't rebuild a to-be-minted block"));
-							continue;
-						}
-
-						newBlocks.add(newBlock);
-					}
-				}
-
-				// No potential block candidates?
-				if (newBlocks.isEmpty())
-					continue;
-
-				// Make sure we're the only thread modifying the blockchain
-				ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
-				if (!blockchainLock.tryLock(30, TimeUnit.SECONDS)) {
-					LOGGER.debug("Couldn't acquire blockchain lock even after waiting 30 seconds");
-					continue;
-				}
-
-				boolean newBlockMinted = false;
-				Block newBlock = null;
-
 				try {
-					// Clear repository session state so we have latest view of data
+					// Free up any repository locks
 					repository.discardChanges();
 
-					// Now that we have blockchain lock, do final check that chain hasn't changed
-					BlockData latestBlockData = blockRepository.getLastBlock();
-					if (!Arrays.equals(lastBlockData.getSignature(), latestBlockData.getSignature()))
+					// Sleep for a while
+					Thread.sleep(1000);
+
+					isMintingPossible = false;
+
+					final Long now = NTP.getTime();
+					if (now == null)
 						continue;
 
-					List<Block> goodBlocks = new ArrayList<>();
-					for (Block testBlock : newBlocks) {
-						// Is new block's timestamp valid yet?
-						// We do a separate check as some timestamp checks are skipped for testchains
-						if (testBlock.isTimestampValid() != ValidationResult.OK)
-							continue;
+					final Long minLatestBlockTimestamp = Controller.getMinimumLatestBlockTimestamp();
+					if (minLatestBlockTimestamp == null)
+						continue;
 
-						testBlock.preProcess();
+					// No online accounts for current timestamp? (e.g. during startup)
+					if (!OnlineAccountsManager.getInstance().hasOnlineAccounts())
+						continue;
 
-						// Is new block valid yet? (Before adding unconfirmed transactions)
-						ValidationResult result = testBlock.isValid();
-						if (result != ValidationResult.OK) {
-							moderatedLog(() -> LOGGER.error(String.format("To-be-minted block invalid '%s' before adding transactions?", result.name())));
+					List<MintingAccountData> mintingAccountsData = repository.getAccountRepository().getMintingAccounts();
+					// No minting accounts?
+					if (mintingAccountsData.isEmpty())
+						continue;
 
+					// Disregard minting accounts that are no longer valid, e.g. by transfer/loss of founder flag or account level
+					// Note that minting accounts are actually reward-shares in Qortal
+					Iterator<MintingAccountData> madi = mintingAccountsData.iterator();
+					while (madi.hasNext()) {
+						MintingAccountData mintingAccountData = madi.next();
+
+						RewardShareData rewardShareData = repository.getAccountRepository().getRewardShare(mintingAccountData.getPublicKey());
+						if (rewardShareData == null) {
+							// Reward-share doesn't exist - probably cancelled but not yet removed from node's list of minting accounts
+							madi.remove();
 							continue;
 						}
 
-						goodBlocks.add(testBlock);
-					}
+						Account mintingAccount = new Account(repository, rewardShareData.getMinter());
+						if (!mintingAccount.canMint()) {
+							// Minting-account component of reward-share can no longer mint - disregard
+							madi.remove();
+							continue;
+						}
 
-					if (goodBlocks.isEmpty())
-						continue;
-
-					// Pick best block
-					final int parentHeight = previousBlockData.getHeight();
-					final byte[] parentBlockSignature = previousBlockData.getSignature();
-
-					BigInteger bestWeight = null;
-
-					for (int bi = 0; bi < goodBlocks.size(); ++bi) {
-						BlockData blockData = goodBlocks.get(bi).getBlockData();
-
-						BlockSummaryData blockSummaryData = new BlockSummaryData(blockData);
-						int minterLevel = Account.getRewardShareEffectiveMintingLevel(repository, blockData.getMinterPublicKey());
-						blockSummaryData.setMinterLevel(minterLevel);
-
-						BigInteger blockWeight = Block.calcBlockWeight(parentHeight, parentBlockSignature, blockSummaryData);
-
-						if (bestWeight == null || blockWeight.compareTo(bestWeight) < 0) {
-							newBlock = goodBlocks.get(bi);
-							bestWeight = blockWeight;
+						// Optional (non-validated) prevention of block submissions below a defined level.
+						// This is an unvalidated version of Blockchain.minAccountLevelToMint
+						// and exists only to reduce block candidates by default.
+						int level = mintingAccount.getEffectiveMintingLevel();
+						if (level < BlockChain.getInstance().getMinAccountLevelForBlockSubmissions()) {
+							madi.remove();
+							continue;
 						}
 					}
 
-					try {
-						if (this.higherWeightChainExists(repository, bestWeight)) {
+					// Needs a mutable copy of the unmodifiableList
+					List<Peer> peers = new ArrayList<>(Network.getInstance().getImmutableHandshakedPeers());
+					BlockData lastBlockData = blockRepository.getLastBlock();
 
-							// Check if the base block has updated since the last time we were here
-							if (parentSignatureForLastLowWeightBlock == null || timeOfLastLowWeightBlock == null ||
-									!Arrays.equals(parentSignatureForLastLowWeightBlock, previousBlockData.getSignature())) {
-								// We've switched to a different chain, so reset the timer
-								timeOfLastLowWeightBlock = NTP.getTime();
+					// Disregard peers that have "misbehaved" recently
+					peers.removeIf(Controller.hasMisbehaved);
+
+					// Disregard peers that don't have a recent block, but only if we're not in recovery mode.
+					// In that mode, we want to allow minting on top of older blocks, to recover stalled networks.
+					if (Synchronizer.getInstance().getRecoveryMode() == false)
+						peers.removeIf(Controller.hasNoRecentBlock);
+
+					// Don't mint if we don't have enough up-to-date peers as where would the transactions/consensus come from?
+					if (peers.size() < Settings.getInstance().getMinBlockchainPeers())
+						continue;
+
+					// If we are stuck on an invalid block, we should allow an alternative to be minted
+					boolean recoverInvalidBlock = false;
+					if (Synchronizer.getInstance().timeInvalidBlockLastReceived != null) {
+						// We've had at least one invalid block
+						long timeSinceLastValidBlock = NTP.getTime() - Synchronizer.getInstance().timeValidBlockLastReceived;
+						long timeSinceLastInvalidBlock = NTP.getTime() - Synchronizer.getInstance().timeInvalidBlockLastReceived;
+						if (timeSinceLastValidBlock > INVALID_BLOCK_RECOVERY_TIMEOUT) {
+							if (timeSinceLastInvalidBlock < INVALID_BLOCK_RECOVERY_TIMEOUT) {
+								// Last valid block was more than 10 mins ago, but we've had an invalid block since then
+								// Assume that the chain has stalled because there is no alternative valid candidate
+								// Enter recovery mode to allow alternative, valid candidates to be minted
+								recoverInvalidBlock = true;
 							}
-							parentSignatureForLastLowWeightBlock = previousBlockData.getSignature();
+						}
+					}
 
-							// If less than 30 seconds has passed since first detection the higher weight chain,
-							// we should skip our block submission to give us the opportunity to sync to the better chain
-							if (NTP.getTime() - timeOfLastLowWeightBlock < 30*1000L) {
-								LOGGER.info("Higher weight chain found in peers, so not signing a block this round");
-								LOGGER.info("Time since detected: {}", NTP.getTime() - timeOfLastLowWeightBlock);
+					// If our latest block isn't recent then we need to synchronize instead of minting, unless we're in recovery mode.
+					if (!peers.isEmpty() && lastBlockData.getTimestamp() < minLatestBlockTimestamp)
+						if (Synchronizer.getInstance().getRecoveryMode() == false && recoverInvalidBlock == false)
+							continue;
+
+					// There are enough peers with a recent block and our latest block is recent
+					// so go ahead and mint a block if possible.
+					isMintingPossible = true;
+
+					// Check blockchain hasn't changed
+					if (previousBlockData == null || !Arrays.equals(previousBlockData.getSignature(), lastBlockData.getSignature())) {
+						previousBlockData = lastBlockData;
+						newBlocks.clear();
+
+						// Reduce log timeout
+						logTimeout = 10 * 1000L;
+
+						// Last low weight block is no longer valid
+						parentSignatureForLastLowWeightBlock = null;
+					}
+
+					// Discard accounts we have already built blocks with
+					mintingAccountsData.removeIf(mintingAccountData -> newBlocks.stream().anyMatch(newBlock -> Arrays.equals(newBlock.getBlockData().getMinterPublicKey(), mintingAccountData.getPublicKey())));
+
+					// Do we need to build any potential new blocks?
+					List<PrivateKeyAccount> newBlocksMintingAccounts = mintingAccountsData.stream().map(accountData -> new PrivateKeyAccount(repository, accountData.getPrivateKey())).collect(Collectors.toList());
+
+					// We might need to sit the next block out, if one of our minting accounts signed the previous one
+					byte[] previousBlockMinter = previousBlockData.getMinterPublicKey();
+					boolean mintedLastBlock = mintingAccountsData.stream().anyMatch(mintingAccount -> Arrays.equals(mintingAccount.getPublicKey(), previousBlockMinter));
+					if (mintedLastBlock) {
+						LOGGER.trace(String.format("One of our keys signed the last block, so we won't sign the next one"));
+						continue;
+					}
+
+					if (parentSignatureForLastLowWeightBlock != null) {
+						// The last iteration found a higher weight block in the network, so sleep for a while
+						// to allow is to sync the higher weight chain. We are sleeping here rather than when
+						// detected as we don't want to hold the blockchain lock open.
+						LOGGER.info("Sleeping for 10 seconds...");
+						Thread.sleep(10 * 1000L);
+					}
+
+					for (PrivateKeyAccount mintingAccount : newBlocksMintingAccounts) {
+						// First block does the AT heavy-lifting
+						if (newBlocks.isEmpty()) {
+							Block newBlock = Block.mint(repository, previousBlockData, mintingAccount);
+							if (newBlock == null) {
+								// For some reason we can't mint right now
+								moderatedLog(() -> LOGGER.error("Couldn't build a to-be-minted block"));
 								continue;
 							}
-							else {
-								// More than 30 seconds have passed, so we should submit our block candidate anyway.
-								LOGGER.info("More than 30 seconds passed, so proceeding to submit block candidate...");
+
+							newBlocks.add(newBlock);
+						} else {
+							// The blocks for other minters require less effort...
+							Block newBlock = newBlocks.get(0).remint(mintingAccount);
+							if (newBlock == null) {
+								// For some reason we can't mint right now
+								moderatedLog(() -> LOGGER.error("Couldn't rebuild a to-be-minted block"));
+								continue;
 							}
+
+							newBlocks.add(newBlock);
 						}
-						else {
-							LOGGER.debug("No higher weight chain found in peers");
-						}
-					} catch (DataException e) {
-						LOGGER.debug("Unable to check for a higher weight chain. Proceeding anyway...");
 					}
 
-					// Discard any uncommitted changes as a result of the higher weight chain detection
-					repository.discardChanges();
+					// No potential block candidates?
+					if (newBlocks.isEmpty())
+						continue;
 
-					// Clear variables that track low weight blocks
-					parentSignatureForLastLowWeightBlock = null;
-					timeOfLastLowWeightBlock = null;
-
-
-					// Add unconfirmed transactions
-					addUnconfirmedTransactions(repository, newBlock);
-
-					// Sign to create block's signature
-					newBlock.sign();
-
-					// Is newBlock still valid?
-					ValidationResult validationResult = newBlock.isValid();
-					if (validationResult != ValidationResult.OK) {
-						// No longer valid? Report and discard
-						LOGGER.error(String.format("To-be-minted block now invalid '%s' after adding unconfirmed transactions?", validationResult.name()));
-
-						// Rebuild block candidates, just to be sure
-						newBlocks.clear();
+					// Make sure we're the only thread modifying the blockchain
+					ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+					if (!blockchainLock.tryLock(30, TimeUnit.SECONDS)) {
+						LOGGER.debug("Couldn't acquire blockchain lock even after waiting 30 seconds");
 						continue;
 					}
 
-					// Add to blockchain - something else will notice and broadcast new block to network
+					boolean newBlockMinted = false;
+					Block newBlock = null;
+
 					try {
-						newBlock.process();
+						// Clear repository session state so we have latest view of data
+						repository.discardChanges();
 
-						repository.saveChanges();
+						// Now that we have blockchain lock, do final check that chain hasn't changed
+						BlockData latestBlockData = blockRepository.getLastBlock();
+						if (!Arrays.equals(lastBlockData.getSignature(), latestBlockData.getSignature()))
+							continue;
 
-						LOGGER.info(String.format("Minted new block: %d", newBlock.getBlockData().getHeight()));
+						List<Block> goodBlocks = new ArrayList<>();
+						boolean wasInvalidBlockDiscarded = false;
+						Iterator<Block> newBlocksIterator = newBlocks.iterator();
 
-						RewardShareData rewardShareData = repository.getAccountRepository().getRewardShare(newBlock.getBlockData().getMinterPublicKey());
+						while (newBlocksIterator.hasNext()) {
+							Block testBlock = newBlocksIterator.next();
 
-						if (rewardShareData != null) {
-							LOGGER.info(String.format("Minted block %d, sig %.8s, parent sig: %.8s by %s on behalf of %s",
-									newBlock.getBlockData().getHeight(),
-									Base58.encode(newBlock.getBlockData().getSignature()),
-									Base58.encode(newBlock.getParent().getSignature()),
-									rewardShareData.getMinter(),
-									rewardShareData.getRecipient()));
-						} else {
-							LOGGER.info(String.format("Minted block %d, sig %.8s, parent sig: %.8s by %s",
-									newBlock.getBlockData().getHeight(),
-									Base58.encode(newBlock.getBlockData().getSignature()),
-									Base58.encode(newBlock.getParent().getSignature()),
-									newBlock.getMinter().getAddress()));
+							// Is new block's timestamp valid yet?
+							// We do a separate check as some timestamp checks are skipped for testchains
+							if (testBlock.isTimestampValid() != ValidationResult.OK)
+								continue;
+
+							testBlock.preProcess();
+
+							// Is new block valid yet? (Before adding unconfirmed transactions)
+							ValidationResult result = testBlock.isValid();
+							if (result != ValidationResult.OK) {
+								moderatedLog(() -> LOGGER.error(String.format("To-be-minted block invalid '%s' before adding transactions?", result.name())));
+
+								newBlocksIterator.remove();
+								wasInvalidBlockDiscarded = true;
+								/*
+								 * Bail out fast so that we loop around from the top again.
+								 * This gives BlockMinter the possibility to remint this candidate block using another block from newBlocks,
+								 * via the Blocks.remint() method, which avoids having to re-process Block ATs all over again.
+								 * Particularly useful if some aspect of Blocks changes due a timestamp-based feature-trigger (see BlockChain class).
+								 */
+								break;
+							}
+
+							goodBlocks.add(testBlock);
 						}
 
-						// Notify network after we're released blockchain lock
-						newBlockMinted = true;
+						if (wasInvalidBlockDiscarded || goodBlocks.isEmpty())
+							continue;
 
-						// Notify Controller
-						repository.discardChanges(); // clear transaction status to prevent deadlocks
-						Controller.getInstance().onNewBlock(newBlock.getBlockData());
-					} catch (DataException e) {
-						// Unable to process block - report and discard
-						LOGGER.error("Unable to process newly minted block?", e);
-						newBlocks.clear();
+						// Pick best block
+						final int parentHeight = previousBlockData.getHeight();
+						final byte[] parentBlockSignature = previousBlockData.getSignature();
+
+						BigInteger bestWeight = null;
+
+						for (int bi = 0; bi < goodBlocks.size(); ++bi) {
+							BlockData blockData = goodBlocks.get(bi).getBlockData();
+
+							BlockSummaryData blockSummaryData = new BlockSummaryData(blockData);
+							int minterLevel = Account.getRewardShareEffectiveMintingLevel(repository, blockData.getMinterPublicKey());
+							blockSummaryData.setMinterLevel(minterLevel);
+
+							BigInteger blockWeight = Block.calcBlockWeight(parentHeight, parentBlockSignature, blockSummaryData);
+
+							if (bestWeight == null || blockWeight.compareTo(bestWeight) < 0) {
+								newBlock = goodBlocks.get(bi);
+								bestWeight = blockWeight;
+							}
+						}
+
+						try {
+							if (this.higherWeightChainExists(repository, bestWeight)) {
+
+								// Check if the base block has updated since the last time we were here
+								if (parentSignatureForLastLowWeightBlock == null || timeOfLastLowWeightBlock == null ||
+										!Arrays.equals(parentSignatureForLastLowWeightBlock, previousBlockData.getSignature())) {
+									// We've switched to a different chain, so reset the timer
+									timeOfLastLowWeightBlock = NTP.getTime();
+								}
+								parentSignatureForLastLowWeightBlock = previousBlockData.getSignature();
+
+								// If less than 30 seconds has passed since first detection the higher weight chain,
+								// we should skip our block submission to give us the opportunity to sync to the better chain
+								if (NTP.getTime() - timeOfLastLowWeightBlock < 30 * 1000L) {
+									LOGGER.info("Higher weight chain found in peers, so not signing a block this round");
+									LOGGER.info("Time since detected: {}", NTP.getTime() - timeOfLastLowWeightBlock);
+									continue;
+								} else {
+									// More than 30 seconds have passed, so we should submit our block candidate anyway.
+									LOGGER.info("More than 30 seconds passed, so proceeding to submit block candidate...");
+								}
+							} else {
+								LOGGER.debug("No higher weight chain found in peers");
+							}
+						} catch (DataException e) {
+							LOGGER.debug("Unable to check for a higher weight chain. Proceeding anyway...");
+						}
+
+						// Discard any uncommitted changes as a result of the higher weight chain detection
+						repository.discardChanges();
+
+						// Clear variables that track low weight blocks
+						parentSignatureForLastLowWeightBlock = null;
+						timeOfLastLowWeightBlock = null;
+
+						// Add unconfirmed transactions
+						addUnconfirmedTransactions(repository, newBlock);
+
+						// Sign to create block's signature
+						newBlock.sign();
+
+						// Is newBlock still valid?
+						ValidationResult validationResult = newBlock.isValid();
+						if (validationResult != ValidationResult.OK) {
+							// No longer valid? Report and discard
+							LOGGER.error(String.format("To-be-minted block now invalid '%s' after adding unconfirmed transactions?", validationResult.name()));
+
+							// Rebuild block candidates, just to be sure
+							newBlocks.clear();
+							continue;
+						}
+
+						// Add to blockchain - something else will notice and broadcast new block to network
+						try {
+							newBlock.process();
+
+							repository.saveChanges();
+
+							LOGGER.info(String.format("Minted new block: %d", newBlock.getBlockData().getHeight()));
+
+							RewardShareData rewardShareData = repository.getAccountRepository().getRewardShare(newBlock.getBlockData().getMinterPublicKey());
+
+							if (rewardShareData != null) {
+								LOGGER.info(String.format("Minted block %d, sig %.8s, parent sig: %.8s by %s on behalf of %s",
+										newBlock.getBlockData().getHeight(),
+										Base58.encode(newBlock.getBlockData().getSignature()),
+										Base58.encode(newBlock.getParent().getSignature()),
+										rewardShareData.getMinter(),
+										rewardShareData.getRecipient()));
+							} else {
+								LOGGER.info(String.format("Minted block %d, sig %.8s, parent sig: %.8s by %s",
+										newBlock.getBlockData().getHeight(),
+										Base58.encode(newBlock.getBlockData().getSignature()),
+										Base58.encode(newBlock.getParent().getSignature()),
+										newBlock.getMinter().getAddress()));
+							}
+
+							// Notify network after we're released blockchain lock
+							newBlockMinted = true;
+
+							// Notify Controller
+							repository.discardChanges(); // clear transaction status to prevent deadlocks
+							Controller.getInstance().onNewBlock(newBlock.getBlockData());
+						} catch (DataException e) {
+							// Unable to process block - report and discard
+							LOGGER.error("Unable to process newly minted block?", e);
+							newBlocks.clear();
+						}
+					} finally {
+						blockchainLock.unlock();
 					}
-				} finally {
-					blockchainLock.unlock();
-				}
 
-				if (newBlockMinted) {
-					// Broadcast our new chain to network
-					BlockData newBlockData = newBlock.getBlockData();
+					if (newBlockMinted) {
+						// Broadcast our new chain to network
+						Network.getInstance().broadcastOurChain();
+					}
 
-					Network network = Network.getInstance();
-					network.broadcast(broadcastPeer -> network.buildHeightMessage(broadcastPeer, newBlockData));
+				} catch (InterruptedException e) {
+					// We've been interrupted - time to exit
+					return;
 				}
 			}
 		} catch (DataException e) {
-			LOGGER.warn("Repository issue while running block minter", e);
-		} catch (InterruptedException e) {
-			// We've been interrupted - time to exit
-			return;
+			LOGGER.warn("Repository issue while running block minter - NO LONGER MINTING", e);
 		}
 	}
 
@@ -552,18 +576,23 @@ public class BlockMinter extends Thread {
 				// This peer has common block data
 				CommonBlockData commonBlockData = peer.getCommonBlockData();
 				BlockSummaryData commonBlockSummaryData = commonBlockData.getCommonBlockSummary();
-				if (commonBlockData.getChainWeight() != null) {
+				if (commonBlockData.getChainWeight() != null && peer.getCommonBlockData().getBlockSummariesAfterCommonBlock() != null) {
 					// The synchronizer has calculated this peer's chain weight
-					BigInteger ourChainWeightSinceCommonBlock = this.getOurChainWeightSinceBlock(repository, commonBlockSummaryData, commonBlockData.getBlockSummariesAfterCommonBlock());
-					BigInteger ourChainWeight = ourChainWeightSinceCommonBlock.add(blockCandidateWeight);
-					BigInteger peerChainWeight = commonBlockData.getChainWeight();
-					if (peerChainWeight.compareTo(ourChainWeight) >= 0) {
-						// This peer has a higher weight chain than ours
-						LOGGER.debug("Peer {} is on a higher weight chain ({}) than ours ({})", peer, formatter.format(peerChainWeight), formatter.format(ourChainWeight));
-						return true;
+					if (!Synchronizer.getInstance().containsInvalidBlockSummary(peer.getCommonBlockData().getBlockSummariesAfterCommonBlock())) {
+						// .. and it doesn't hold any invalid blocks
+						BigInteger ourChainWeightSinceCommonBlock = this.getOurChainWeightSinceBlock(repository, commonBlockSummaryData, commonBlockData.getBlockSummariesAfterCommonBlock());
+						BigInteger ourChainWeight = ourChainWeightSinceCommonBlock.add(blockCandidateWeight);
+						BigInteger peerChainWeight = commonBlockData.getChainWeight();
+						if (peerChainWeight.compareTo(ourChainWeight) >= 0) {
+							// This peer has a higher weight chain than ours
+							LOGGER.info("Peer {} is on a higher weight chain ({}) than ours ({})", peer, formatter.format(peerChainWeight), formatter.format(ourChainWeight));
+							return true;
 
+						} else {
+							LOGGER.debug("Peer {} is on a lower weight chain ({}) than ours ({})", peer, formatter.format(peerChainWeight), formatter.format(ourChainWeight));
+						}
 					} else {
-						LOGGER.debug("Peer {} is on a lower weight chain ({}) than ours ({})", peer, formatter.format(peerChainWeight), formatter.format(ourChainWeight));
+						LOGGER.debug("Peer {} has an invalid block", peer);
 					}
 				} else {
 					LOGGER.debug("Peer {} has no chain weight", peer);

src/main/java/org/qortal/controller/Controller.java

@@ -32,6 +32,7 @@ import org.bouncycastle.jsse.provider.BouncyCastleJsseProvider;
 import org.qortal.api.ApiService;
 import org.qortal.api.DomainMapService;
 import org.qortal.api.GatewayService;
+import org.qortal.api.resource.TransactionsResource;
 import org.qortal.block.Block;
 import org.qortal.block.BlockChain;
 import org.qortal.block.BlockChain.BlockTimingByHeight;
@@ -39,9 +40,11 @@ import org.qortal.controller.arbitrary.*;
 import org.qortal.controller.repository.PruneManager;
 import org.qortal.controller.repository.NamesDatabaseIntegrityCheck;
 import org.qortal.controller.tradebot.TradeBot;
+import org.qortal.data.account.AccountBalanceData;
+import org.qortal.data.account.AccountData;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
-import org.qortal.data.network.PeerChainTipData;
+import org.qortal.data.naming.NameData;
 import org.qortal.data.network.PeerData;
 import org.qortal.data.transaction.ChatTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -58,6 +61,7 @@ import org.qortal.repository.hsqldb.HSQLDBRepositoryFactory;
 import org.qortal.settings.Settings;
 import org.qortal.transaction.Transaction;
 import org.qortal.transaction.Transaction.TransactionType;
+import org.qortal.transform.TransformationException;
 import org.qortal.utils.*;
 
 public class Controller extends Thread {
@@ -108,6 +112,7 @@ public class Controller extends Thread {
 	private long repositoryBackupTimestamp = startTime; // ms
 	private long repositoryMaintenanceTimestamp = startTime; // ms
 	private long repositoryCheckpointTimestamp = startTime; // ms
+	private long prunePeersTimestamp = startTime; // ms
 	private long ntpCheckTimestamp = startTime; // ms
 	private long deleteExpiredTimestamp = startTime + DELETE_EXPIRED_INTERVAL; // ms
 
@@ -178,6 +183,52 @@ public class Controller extends Thread {
 		}
 		public GetArbitraryMetadataMessageStats getArbitraryMetadataMessageStats = new GetArbitraryMetadataMessageStats();
 
+		public static class GetAccountMessageStats {
+			public AtomicLong requests = new AtomicLong();
+			public AtomicLong cacheHits = new AtomicLong();
+			public AtomicLong unknownAccounts = new AtomicLong();
+
+			public GetAccountMessageStats() {
+			}
+		}
+		public GetAccountMessageStats getAccountMessageStats = new GetAccountMessageStats();
+
+		public static class GetAccountBalanceMessageStats {
+			public AtomicLong requests = new AtomicLong();
+			public AtomicLong unknownAccounts = new AtomicLong();
+
+			public GetAccountBalanceMessageStats() {
+			}
+		}
+		public GetAccountBalanceMessageStats getAccountBalanceMessageStats = new GetAccountBalanceMessageStats();
+
+		public static class GetAccountTransactionsMessageStats {
+			public AtomicLong requests = new AtomicLong();
+			public AtomicLong unknownAccounts = new AtomicLong();
+
+			public GetAccountTransactionsMessageStats() {
+			}
+		}
+		public GetAccountTransactionsMessageStats getAccountTransactionsMessageStats = new GetAccountTransactionsMessageStats();
+
+		public static class GetAccountNamesMessageStats {
+			public AtomicLong requests = new AtomicLong();
+			public AtomicLong unknownAccounts = new AtomicLong();
+
+			public GetAccountNamesMessageStats() {
+			}
+		}
+		public GetAccountNamesMessageStats getAccountNamesMessageStats = new GetAccountNamesMessageStats();
+
+		public static class GetNameMessageStats {
+			public AtomicLong requests = new AtomicLong();
+			public AtomicLong unknownAccounts = new AtomicLong();
+
+			public GetNameMessageStats() {
+			}
+		}
+		public GetNameMessageStats getNameMessageStats = new GetNameMessageStats();
+
 		public AtomicLong latestBlocksCacheRefills = new AtomicLong();
 
 		public StatsSnapshot() {
@@ -265,6 +316,10 @@ public class Controller extends Thread {
 		}
 	}
 
+	public static long uptime() {
+		return System.currentTimeMillis() - Controller.startTime;
+	}
+
 	/** Returns highest block, or null if it's not available. */
 	public BlockData getChainTip() {
 		synchronized (this.latestBlocks) {
@@ -362,23 +417,27 @@ public class Controller extends Thread {
 			return; // Not System.exit() so that GUI can display error
 		}
 
-		// Rebuild Names table and check database integrity (if enabled)
-		NamesDatabaseIntegrityCheck namesDatabaseIntegrityCheck = new NamesDatabaseIntegrityCheck();
-		namesDatabaseIntegrityCheck.rebuildAllNames();
-		if (Settings.getInstance().isNamesIntegrityCheckEnabled()) {
-			namesDatabaseIntegrityCheck.runIntegrityCheck();
-		}
+		// If we have a non-lite node, we need to perform some startup actions
+		if (!Settings.getInstance().isLite()) {
 
-		LOGGER.info("Validating blockchain");
-		try {
-			BlockChain.validate();
+			// Rebuild Names table and check database integrity (if enabled)
+			NamesDatabaseIntegrityCheck namesDatabaseIntegrityCheck = new NamesDatabaseIntegrityCheck();
+			namesDatabaseIntegrityCheck.rebuildAllNames();
+			if (Settings.getInstance().isNamesIntegrityCheckEnabled()) {
+				namesDatabaseIntegrityCheck.runIntegrityCheck();
+			}
 
-			Controller.getInstance().refillLatestBlocksCache();
-			LOGGER.info(String.format("Our chain height at start-up: %d", Controller.getInstance().getChainHeight()));
-		} catch (DataException e) {
-			LOGGER.error("Couldn't validate blockchain", e);
-			Gui.getInstance().fatalError("Blockchain validation issue", e);
-			return; // Not System.exit() so that GUI can display error
+			LOGGER.info("Validating blockchain");
+			try {
+				BlockChain.validate();
+
+				Controller.getInstance().refillLatestBlocksCache();
+				LOGGER.info(String.format("Our chain height at start-up: %d", Controller.getInstance().getChainHeight()));
+			} catch (DataException e) {
+				LOGGER.error("Couldn't validate blockchain", e);
+				Gui.getInstance().fatalError("Blockchain validation issue", e);
+				return; // Not System.exit() so that GUI can display error
+			}
 		}
 
 		// Import current trade bot states and minting accounts if they exist
@@ -441,6 +500,9 @@ public class Controller extends Thread {
 			AutoUpdate.getInstance().start();
 		}
 
+		LOGGER.info("Starting wallets");
+		PirateChainWalletController.getInstance().start();
+
 		LOGGER.info(String.format("Starting API on port %d", Settings.getInstance().getApiPort()));
 		try {
 			ApiService apiService = ApiService.getInstance();
@@ -497,6 +559,7 @@ public class Controller extends Thread {
 		final long repositoryBackupInterval = Settings.getInstance().getRepositoryBackupInterval();
 		final long repositoryCheckpointInterval = Settings.getInstance().getRepositoryCheckpointInterval();
 		long repositoryMaintenanceInterval = getRandomRepositoryMaintenanceInterval();
+		final long prunePeersInterval = 5 * 60 * 1000L; // Every 5 minutes
 
 		// Start executor service for trimming or pruning
 		PruneManager.getInstance().start();
@@ -573,15 +636,20 @@ public class Controller extends Thread {
 								MessageType.INFO);
 
 					LOGGER.info("Starting scheduled repository maintenance. This can take a while...");
-					try (final Repository repository = RepositoryManager.getRepository()) {
+					int attempts = 0;
+					while (attempts <= 5) {
+						try (final Repository repository = RepositoryManager.getRepository()) {
+							attempts++;
 
-						// Timeout if the database isn't ready for maintenance after 60 seconds
-						long timeout = 60 * 1000L;
-						repository.performPeriodicMaintenance(timeout);
+							// Timeout if the database isn't ready for maintenance after 60 seconds
+							long timeout = 60 * 1000L;
+							repository.performPeriodicMaintenance(timeout);
 
-						LOGGER.info("Scheduled repository maintenance completed");
-					} catch (DataException | TimeoutException e) {
-						LOGGER.error("Scheduled repository maintenance failed", e);
+							LOGGER.info("Scheduled repository maintenance completed");
+							break;
+						} catch (DataException | TimeoutException e) {
+							LOGGER.info("Scheduled repository maintenance failed. Retrying up to 5 times...", e);
+						}
 					}
 
 					// Get a new random interval
@@ -589,10 +657,15 @@ public class Controller extends Thread {
 				}
 
 				// Prune stuck/slow/old peers
-				try {
-					Network.getInstance().prunePeers();
-				} catch (DataException e) {
-					LOGGER.warn(String.format("Repository issue when trying to prune peers: %s", e.getMessage()));
+				if (now >= prunePeersTimestamp + prunePeersInterval) {
+					prunePeersTimestamp = now + prunePeersInterval;
+
+					try {
+						LOGGER.debug("Pruning peers...");
+						Network.getInstance().prunePeers();
+					} catch (DataException e) {
+						LOGGER.warn(String.format("Repository issue when trying to prune peers: %s", e.getMessage()));
+					}
 				}
 
 				// Delete expired transactions
@@ -655,50 +728,27 @@ public class Controller extends Thread {
 		return lastMisbehaved != null && lastMisbehaved > NTP.getTime() - MISBEHAVIOUR_COOLOFF;
 	};
 
-	/** True if peer has unknown height, lower height or same height and same block signature (unless we don't have their block signature). */
-	public static Predicate<Peer> hasShorterBlockchain = peer -> {
-		BlockData highestBlockData = getInstance().getChainTip();
-		int ourHeight = highestBlockData.getHeight();
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-
-		// Ensure we have chain tip data for this peer
-		if (peerChainTipData == null)
-			return true;
-
-		// Remove if peer is at a lower height than us
-		Integer peerHeight = peerChainTipData.getLastHeight();
-		if (peerHeight == null || peerHeight < ourHeight)
-			return true;
-
-		// Don't remove if peer is on a greater height chain than us, or if we don't have their block signature
-		if (peerHeight > ourHeight || peerChainTipData.getLastBlockSignature() == null)
-			return false;
-
-		// Remove if signatures match
-		return Arrays.equals(peerChainTipData.getLastBlockSignature(), highestBlockData.getSignature());
-	};
-
 	public static final Predicate<Peer> hasNoRecentBlock = peer -> {
 		final Long minLatestBlockTimestamp = getMinimumLatestBlockTimestamp();
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-		return peerChainTipData == null || peerChainTipData.getLastBlockTimestamp() == null || peerChainTipData.getLastBlockTimestamp() < minLatestBlockTimestamp;
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		return peerChainTipData == null || peerChainTipData.getTimestamp() == null || peerChainTipData.getTimestamp() < minLatestBlockTimestamp;
 	};
 
 	public static final Predicate<Peer> hasNoOrSameBlock = peer -> {
 		final BlockData latestBlockData = getInstance().getChainTip();
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-		return peerChainTipData == null || peerChainTipData.getLastBlockSignature() == null || Arrays.equals(latestBlockData.getSignature(), peerChainTipData.getLastBlockSignature());
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		return peerChainTipData == null || peerChainTipData.getSignature() == null || Arrays.equals(latestBlockData.getSignature(), peerChainTipData.getSignature());
 	};
 
 	public static final Predicate<Peer> hasOnlyGenesisBlock = peer -> {
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-		return peerChainTipData == null || peerChainTipData.getLastHeight() == null || peerChainTipData.getLastHeight() == 1;
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		return peerChainTipData == null || peerChainTipData.getHeight() == 1;
 	};
 
 	public static final Predicate<Peer> hasInferiorChainTip = peer -> {
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
 		final List<ByteArray> inferiorChainTips = Synchronizer.getInstance().inferiorChainSignatures;
-		return peerChainTipData == null || peerChainTipData.getLastBlockSignature() == null || inferiorChainTips.contains(ByteArray.wrap(peerChainTipData.getLastBlockSignature()));
+		return peerChainTipData == null || peerChainTipData.getSignature() == null || inferiorChainTips.contains(ByteArray.wrap(peerChainTipData.getSignature()));
 	};
 
 	public static final Predicate<Peer> hasOldVersion = peer -> {
@@ -750,19 +800,24 @@ public class Controller extends Thread {
 		String actionText;
 
 		// Use a more tolerant latest block timestamp in the isUpToDate() calls below to reduce misleading statuses.
-		// Any block in the last 30 minutes is considered "up to date" for the purposes of displaying statuses.
-		final Long minLatestBlockTimestamp = NTP.getTime() - (30 * 60 * 1000L);
+		// Any block in the last 2 hours is considered "up to date" for the purposes of displaying statuses.
+		// This also aligns with the time interval required for continued online account submission.
+		final Long minLatestBlockTimestamp = NTP.getTime() - (2 * 60 * 60 * 1000L);
+
+		// Only show sync percent if it's less than 100, to avoid confusion
+		final Integer syncPercent = Synchronizer.getInstance().getSyncPercent();
+		final boolean isSyncing = (syncPercent != null && syncPercent < 100);
 
 		synchronized (Synchronizer.getInstance().syncLock) {
-			if (this.isMintingPossible) {
-				actionText = Translator.INSTANCE.translate("SysTray", "MINTING_ENABLED");
-				SysTray.getInstance().setTrayIcon(2);
+			if (Settings.getInstance().isLite()) {
+				actionText = Translator.INSTANCE.translate("SysTray", "LITE_NODE");
+				SysTray.getInstance().setTrayIcon(4);
 			}
 			else if (numberOfPeers < Settings.getInstance().getMinBlockchainPeers()) {
 				actionText = Translator.INSTANCE.translate("SysTray", "CONNECTING");
 				SysTray.getInstance().setTrayIcon(3);
 			}
-			else if (!this.isUpToDate(minLatestBlockTimestamp) && Synchronizer.getInstance().isSynchronizing()) {
+			else if (!this.isUpToDate(minLatestBlockTimestamp) && isSyncing) {
 				actionText = String.format("%s - %d%%", Translator.INSTANCE.translate("SysTray", "SYNCHRONIZING_BLOCKCHAIN"), Synchronizer.getInstance().getSyncPercent());
 				SysTray.getInstance().setTrayIcon(3);
 			}
@@ -770,13 +825,21 @@ public class Controller extends Thread {
 				actionText = String.format("%s", Translator.INSTANCE.translate("SysTray", "SYNCHRONIZING_BLOCKCHAIN"));
 				SysTray.getInstance().setTrayIcon(3);
 			}
+			else if (OnlineAccountsManager.getInstance().hasActiveOnlineAccountSignatures()) {
+				actionText = Translator.INSTANCE.translate("SysTray", "MINTING_ENABLED");
+				SysTray.getInstance().setTrayIcon(2);
+			}
 			else {
 				actionText = Translator.INSTANCE.translate("SysTray", "MINTING_DISABLED");
 				SysTray.getInstance().setTrayIcon(4);
 			}
 		}
 
-		String tooltip = String.format("%s - %d %s - %s %d", actionText, numberOfPeers, connectionsText, heightText, height) + "\n" + String.format("%s: %s", Translator.INSTANCE.translate("SysTray", "BUILD_VERSION"), this.buildVersion);
+		String tooltip = String.format("%s - %d %s", actionText, numberOfPeers, connectionsText);
+		if (!Settings.getInstance().isLite()) {
+			tooltip = tooltip.concat(String.format(" - %s %d", heightText, height));
+		}
+		tooltip = tooltip.concat(String.format("\n%s: %s", Translator.INSTANCE.translate("SysTray", "BUILD_VERSION"), this.buildVersion));
 		SysTray.getInstance().setToolTipText(tooltip);
 
 		this.callbackExecutor.execute(() -> {
@@ -833,6 +896,9 @@ public class Controller extends Thread {
 				LOGGER.info("Shutting down API");
 				ApiService.getInstance().stop();
 
+				LOGGER.info("Shutting down wallets");
+				PirateChainWalletController.getInstance().shutdown();
+
 				if (Settings.getInstance().isAutoUpdateEnabled()) {
 					LOGGER.info("Shutting down auto-update");
 					AutoUpdate.getInstance().shutdown();
@@ -933,14 +999,18 @@ public class Controller extends Thread {
 	// Callbacks for/from network
 
 	public void doNetworkBroadcast() {
+		if (Settings.getInstance().isLite()) {
+			// Lite nodes have nothing to broadcast
+			return;
+		}
+
 		Network network = Network.getInstance();
 
 		// Send (if outbound) / Request peer lists
 		network.broadcast(peer -> peer.isOutbound() ? network.buildPeersMessage(peer) : new GetPeersMessage());
 
 		// Send our current height
-		BlockData latestBlockData = getChainTip();
-		network.broadcast(peer -> network.buildHeightMessage(peer, latestBlockData));
+		network.broadcastOurChain();
 
 		// Request unconfirmed transaction signatures, but only if we're up-to-date.
 		// If we're NOT up-to-date then priority is synchronizing first
@@ -1147,6 +1217,10 @@ public class Controller extends Thread {
 				onNetworkHeightV2Message(peer, message);
 				break;
 
+			case BLOCK_SUMMARIES_V2:
+				onNetworkBlockSummariesV2Message(peer, message);
+				break;
+
 			case GET_TRANSACTION:
 				TransactionImporter.getInstance().onNetworkGetTransactionMessage(peer, message);
 				break;
@@ -1164,19 +1238,18 @@ public class Controller extends Thread {
 				break;
 
 			case GET_ONLINE_ACCOUNTS:
-				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsMessage(peer, message);
-				break;
-
 			case ONLINE_ACCOUNTS:
-				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsMessage(peer, message);
-				break;
-
 			case GET_ONLINE_ACCOUNTS_V2:
-				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsV2Message(peer, message);
+			case ONLINE_ACCOUNTS_V2:
+				// No longer supported - to be eventually removed
 				break;
 
-			case ONLINE_ACCOUNTS_V2:
-				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsV2Message(peer, message);
+			case GET_ONLINE_ACCOUNTS_V3:
+				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsV3Message(peer, message);
+				break;
+
+			case ONLINE_ACCOUNTS_V3:
+				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsV3Message(peer, message);
 				break;
 
 			case GET_ARBITRARY_DATA:
@@ -1215,6 +1288,26 @@ public class Controller extends Thread {
 				TradeBot.getInstance().onTradePresencesMessage(peer, message);
 				break;
 
+			case GET_ACCOUNT:
+				onNetworkGetAccountMessage(peer, message);
+				break;
+
+			case GET_ACCOUNT_BALANCE:
+				onNetworkGetAccountBalanceMessage(peer, message);
+				break;
+
+			case GET_ACCOUNT_TRANSACTIONS:
+				onNetworkGetAccountTransactionsMessage(peer, message);
+				break;
+
+			case GET_ACCOUNT_NAMES:
+				onNetworkGetAccountNamesMessage(peer, message);
+				break;
+
+			case GET_NAME:
+				onNetworkGetNameMessage(peer, message);
+				break;
+
 			default:
 				LOGGER.debug(() -> String.format("Unhandled %s message [ID %d] from peer %s", message.getType().name(), message.getId(), peer));
 				break;
@@ -1236,7 +1329,7 @@ public class Controller extends Thread {
 			this.stats.getBlockMessageStats.cacheHits.incrementAndGet();
 
 			// We need to duplicate it to prevent multiple threads setting ID on the same message
-			CachedBlockMessage clonedBlockMessage = cachedBlockMessage.cloneWithNewId(message.getId());
+			CachedBlockMessage clonedBlockMessage = Message.cloneWithNewId(cachedBlockMessage, message.getId());
 
 			if (!peer.sendMessage(clonedBlockMessage))
 				peer.disconnect("failed to send block");
@@ -1282,8 +1375,10 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer's synchronizer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'block unknown' response to peer %s for GET_BLOCK request for unknown block %s", peer, Base58.encode(signature)));
 
-				// We'll send empty block summaries message as it's very short
-				Message blockUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message blockUnknownMessage = peer.getPeersVersion() >= GenericUnknownMessage.MINIMUM_PEER_VERSION
+						? new GenericUnknownMessage()
+						: new BlockSummariesMessage(Collections.emptyList());
 				blockUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(blockUnknownMessage))
 					peer.disconnect("failed to send block-unknown response");
@@ -1292,10 +1387,21 @@ public class Controller extends Thread {
 
 			Block block = new Block(repository, blockData);
 
+			// V2 support
+			if (peer.getPeersVersion() >= BlockV2Message.MIN_PEER_VERSION) {
+				Message blockMessage = new BlockV2Message(block);
+				blockMessage.setId(message.getId());
+				if (!peer.sendMessage(blockMessage)) {
+					peer.disconnect("failed to send block");
+					// Don't fall-through to caching because failure to send might be from failure to build message
+					return;
+				}
+				return;
+			}
+
 			CachedBlockMessage blockMessage = new CachedBlockMessage(block);
 			blockMessage.setId(message.getId());
 
-			// This call also causes the other needed data to be pulled in from repository
 			if (!peer.sendMessage(blockMessage)) {
 				peer.disconnect("failed to send block");
 				// Don't fall-through to caching because failure to send might be from failure to build message
@@ -1309,7 +1415,9 @@ public class Controller extends Thread {
 				this.blockMessageCache.put(ByteArray.wrap(blockData.getSignature()), blockMessage);
 			}
 		} catch (DataException e) {
-			LOGGER.error(String.format("Repository issue while send block %s to peer %s", Base58.encode(signature), peer), e);
+			LOGGER.error(String.format("Repository issue while sending block %s to peer %s", Base58.encode(signature), peer), e);
+		} catch (TransformationException e) {
+			LOGGER.error(String.format("Serialization issue while sending block %s to peer %s", Base58.encode(signature), peer), e);
 		}
 	}
 
@@ -1319,11 +1427,15 @@ public class Controller extends Thread {
 		this.stats.getBlockSummariesStats.requests.incrementAndGet();
 
 		// If peer's parent signature matches our latest block signature
-		// then we can short-circuit with an empty response
+		// then we have no blocks after that and can short-circuit with an empty response
 		BlockData chainTip = getChainTip();
 		if (chainTip != null && Arrays.equals(parentSignature, chainTip.getSignature())) {
-			Message blockSummariesMessage = new BlockSummariesMessage(Collections.emptyList());
+			Message blockSummariesMessage = peer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION
+					? new BlockSummariesV2Message(Collections.emptyList())
+					: new BlockSummariesMessage(Collections.emptyList());
+
 			blockSummariesMessage.setId(message.getId());
+
 			if (!peer.sendMessage(blockSummariesMessage))
 				peer.disconnect("failed to send block summaries");
 
@@ -1379,7 +1491,9 @@ public class Controller extends Thread {
 				this.stats.getBlockSummariesStats.fullyFromCache.incrementAndGet();
 		}
 
-		Message blockSummariesMessage = new BlockSummariesMessage(blockSummaries);
+		Message blockSummariesMessage = peer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION
+				? new BlockSummariesV2Message(blockSummaries)
+				: new BlockSummariesMessage(blockSummaries);
 		blockSummariesMessage.setId(message.getId());
 		if (!peer.sendMessage(blockSummariesMessage))
 			peer.disconnect("failed to send block summaries");
@@ -1450,20 +1564,250 @@ public class Controller extends Thread {
 	private void onNetworkHeightV2Message(Peer peer, Message message) {
 		HeightV2Message heightV2Message = (HeightV2Message) message;
 
-		// If peer is inbound and we've not updated their height
-		// then this is probably their initial HEIGHT_V2 message
-		// so they need a corresponding HEIGHT_V2 message from us
-		if (!peer.isOutbound() && (peer.getChainTipData() == null || peer.getChainTipData().getLastHeight() == null))
-			peer.sendMessage(Network.getInstance().buildHeightMessage(peer, getChainTip()));
+		if (!Settings.getInstance().isLite()) {
+			// If peer is inbound and we've not updated their height
+			// then this is probably their initial HEIGHT_V2 message
+			// so they need a corresponding HEIGHT_V2 message from us
+			if (!peer.isOutbound() && peer.getChainTipData() == null) {
+				Message responseMessage = Network.getInstance().buildHeightOrChainTipInfo(peer);
+
+				if (responseMessage == null || !peer.sendMessage(responseMessage)) {
+					peer.disconnect("failed to send our chain tip info");
+					return;
+				}
+			}
+		}
 
 		// Update peer chain tip data
-		PeerChainTipData newChainTipData = new PeerChainTipData(heightV2Message.getHeight(), heightV2Message.getSignature(), heightV2Message.getTimestamp(), heightV2Message.getMinterPublicKey());
+		BlockSummaryData newChainTipData = new BlockSummaryData(heightV2Message.getHeight(), heightV2Message.getSignature(), heightV2Message.getMinterPublicKey(), heightV2Message.getTimestamp());
 		peer.setChainTipData(newChainTipData);
 
 		// Potentially synchronize
 		Synchronizer.getInstance().requestSync();
 	}
 
+	private void onNetworkBlockSummariesV2Message(Peer peer, Message message) {
+		BlockSummariesV2Message blockSummariesV2Message = (BlockSummariesV2Message) message;
+
+		if (!Settings.getInstance().isLite()) {
+			// If peer is inbound and we've not updated their height
+			// then this is probably their initial BLOCK_SUMMARIES_V2 message
+			// so they need a corresponding BLOCK_SUMMARIES_V2 message from us
+			if (!peer.isOutbound() && peer.getChainTipData() == null) {
+				Message responseMessage = Network.getInstance().buildHeightOrChainTipInfo(peer);
+
+				if (responseMessage == null || !peer.sendMessage(responseMessage)) {
+					peer.disconnect("failed to send our chain tip info");
+					return;
+				}
+			}
+		}
+
+		if (message.hasId()) {
+			/*
+			 * Experimental proof-of-concept: discard messages with ID
+			 * These are 'late' reply messages received after timeout has expired,
+			 * having been passed upwards from Peer to Network to Controller.
+			 * Hence, these are NOT simple "here's my chain tip" broadcasts from other peers.
+			 */
+			LOGGER.info("Discarding late {} message with ID {} from {}", message.getType().name(), message.getId(), peer);
+			return;
+		}
+
+		// Update peer chain tip data
+		peer.setChainTipSummaries(blockSummariesV2Message.getBlockSummaries());
+
+		// Potentially synchronize
+		Synchronizer.getInstance().requestSync();
+	}
+
+	private void onNetworkGetAccountMessage(Peer peer, Message message) {
+		GetAccountMessage getAccountMessage = (GetAccountMessage) message;
+		String address = getAccountMessage.getAddress();
+		this.stats.getAccountMessageStats.requests.incrementAndGet();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			AccountData accountData = repository.getAccountRepository().getAccount(address);
+
+			if (accountData == null) {
+				// We don't have this account
+				this.stats.getAccountMessageStats.unknownAccounts.getAndIncrement();
+
+				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
+				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT request for unknown account %s", peer, address));
+
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
+				accountUnknownMessage.setId(message.getId());
+				if (!peer.sendMessage(accountUnknownMessage))
+					peer.disconnect("failed to send account-unknown response");
+				return;
+			}
+
+			AccountMessage accountMessage = new AccountMessage(accountData);
+			accountMessage.setId(message.getId());
+
+			if (!peer.sendMessage(accountMessage)) {
+				peer.disconnect("failed to send account");
+			}
+
+		} catch (DataException e) {
+			LOGGER.error(String.format("Repository issue while send account %s to peer %s", address, peer), e);
+		}
+	}
+
+	private void onNetworkGetAccountBalanceMessage(Peer peer, Message message) {
+		GetAccountBalanceMessage getAccountBalanceMessage = (GetAccountBalanceMessage) message;
+		String address = getAccountBalanceMessage.getAddress();
+		long assetId = getAccountBalanceMessage.getAssetId();
+		this.stats.getAccountBalanceMessageStats.requests.incrementAndGet();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			AccountBalanceData accountBalanceData = repository.getAccountRepository().getBalance(address, assetId);
+
+			if (accountBalanceData == null) {
+				// We don't have this account
+				this.stats.getAccountBalanceMessageStats.unknownAccounts.getAndIncrement();
+
+				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
+				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT_BALANCE request for unknown account %s and asset ID %d", peer, address, assetId));
+
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
+				accountUnknownMessage.setId(message.getId());
+				if (!peer.sendMessage(accountUnknownMessage))
+					peer.disconnect("failed to send account-unknown response");
+				return;
+			}
+
+			AccountBalanceMessage accountMessage = new AccountBalanceMessage(accountBalanceData);
+			accountMessage.setId(message.getId());
+
+			if (!peer.sendMessage(accountMessage)) {
+				peer.disconnect("failed to send account balance");
+			}
+
+		} catch (DataException e) {
+			LOGGER.error(String.format("Repository issue while send balance for account %s and asset ID %d to peer %s", address, assetId, peer), e);
+		}
+	}
+
+	private void onNetworkGetAccountTransactionsMessage(Peer peer, Message message) {
+		GetAccountTransactionsMessage getAccountTransactionsMessage = (GetAccountTransactionsMessage) message;
+		String address = getAccountTransactionsMessage.getAddress();
+		int limit = Math.min(getAccountTransactionsMessage.getLimit(), 100);
+		int offset = getAccountTransactionsMessage.getOffset();
+		this.stats.getAccountTransactionsMessageStats.requests.incrementAndGet();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			List<byte[]> signatures = repository.getTransactionRepository().getSignaturesMatchingCriteria(null, null, null,
+					null, null, null, address, TransactionsResource.ConfirmationStatus.CONFIRMED, limit, offset, false);
+
+			// Expand signatures to transactions
+			List<TransactionData> transactions = new ArrayList<>(signatures.size());
+			for (byte[] signature : signatures) {
+				transactions.add(repository.getTransactionRepository().fromSignature(signature));
+			}
+
+			if (transactions == null) {
+				// We don't have this account
+				this.stats.getAccountTransactionsMessageStats.unknownAccounts.getAndIncrement();
+
+				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
+				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT_TRANSACTIONS request for unknown account %s", peer, address));
+
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
+				accountUnknownMessage.setId(message.getId());
+				if (!peer.sendMessage(accountUnknownMessage))
+					peer.disconnect("failed to send account-unknown response");
+				return;
+			}
+
+			TransactionsMessage transactionsMessage = new TransactionsMessage(transactions);
+			transactionsMessage.setId(message.getId());
+
+			if (!peer.sendMessage(transactionsMessage)) {
+				peer.disconnect("failed to send account transactions");
+			}
+
+		} catch (DataException e) {
+			LOGGER.error(String.format("Repository issue while sending transactions for account %s %d to peer %s", address, peer), e);
+		} catch (MessageException e) {
+			LOGGER.error(String.format("Message serialization issue while sending transactions for account %s %d to peer %s", address, peer), e);
+		}
+	}
+
+	private void onNetworkGetAccountNamesMessage(Peer peer, Message message) {
+		GetAccountNamesMessage getAccountNamesMessage = (GetAccountNamesMessage) message;
+		String address = getAccountNamesMessage.getAddress();
+		this.stats.getAccountNamesMessageStats.requests.incrementAndGet();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			List<NameData> namesDataList = repository.getNameRepository().getNamesByOwner(address);
+
+			if (namesDataList == null) {
+				// We don't have this account
+				this.stats.getAccountNamesMessageStats.unknownAccounts.getAndIncrement();
+
+				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
+				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT_NAMES request for unknown account %s", peer, address));
+
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
+				accountUnknownMessage.setId(message.getId());
+				if (!peer.sendMessage(accountUnknownMessage))
+					peer.disconnect("failed to send account-unknown response");
+				return;
+			}
+
+			NamesMessage namesMessage = new NamesMessage(namesDataList);
+			namesMessage.setId(message.getId());
+
+			if (!peer.sendMessage(namesMessage)) {
+				peer.disconnect("failed to send account names");
+			}
+
+		} catch (DataException e) {
+			LOGGER.error(String.format("Repository issue while send names for account %s to peer %s", address, peer), e);
+		}
+	}
+
+	private void onNetworkGetNameMessage(Peer peer, Message message) {
+		GetNameMessage getNameMessage = (GetNameMessage) message;
+		String name = getNameMessage.getName();
+		this.stats.getNameMessageStats.requests.incrementAndGet();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			NameData nameData = repository.getNameRepository().fromName(name);
+
+			if (nameData == null) {
+				// We don't have this account
+				this.stats.getNameMessageStats.unknownAccounts.getAndIncrement();
+
+				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
+				LOGGER.debug(() -> String.format("Sending 'name unknown' response to peer %s for GET_NAME request for unknown name %s", peer, name));
+
+				// Send generic 'unknown' message as it's very short
+				Message nameUnknownMessage = new GenericUnknownMessage();
+				nameUnknownMessage.setId(message.getId());
+				if (!peer.sendMessage(nameUnknownMessage))
+					peer.disconnect("failed to send name-unknown response");
+				return;
+			}
+
+			NamesMessage namesMessage = new NamesMessage(Arrays.asList(nameData));
+			namesMessage.setId(message.getId());
+
+			if (!peer.sendMessage(namesMessage)) {
+				peer.disconnect("failed to send name data");
+			}
+
+		} catch (DataException e) {
+			LOGGER.error(String.format("Repository issue while send name %s to peer %s", name, peer), e);
+		}
+	}
+
 
 	// Utilities
 
@@ -1493,14 +1837,14 @@ public class Controller extends Thread {
 				continue;
 			}
 
-			final PeerChainTipData peerChainTipData = peer.getChainTipData();
+			BlockSummaryData peerChainTipData = peer.getChainTipData();
 			if (peerChainTipData == null) {
 				iterator.remove();
 				continue;
 			}
 
 			// Disregard peers that don't have a recent block
-			if (peerChainTipData.getLastBlockTimestamp() == null || peerChainTipData.getLastBlockTimestamp() < minLatestBlockTimestamp) {
+			if (peerChainTipData.getTimestamp() == null || peerChainTipData.getTimestamp() < minLatestBlockTimestamp) {
 				iterator.remove();
 				continue;
 			}
@@ -1515,6 +1859,11 @@ public class Controller extends Thread {
 	 * @return boolean - whether our node's blockchain is up to date or not
 	 */
 	public boolean isUpToDate(Long minLatestBlockTimestamp) {
+		if (Settings.getInstance().isLite()) {
+			// Lite nodes are always "up to date"
+			return true;
+		}
+
 		// Do we even have a vaguely recent block?
 		if (minLatestBlockTimestamp == null)
 			return false;

src/main/java/org/qortal/controller/LiteNode.java

@@ -0,0 +1,189 @@
+package org.qortal.controller;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.data.account.AccountBalanceData;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.naming.NameData;
+import org.qortal.data.transaction.TransactionData;
+import org.qortal.network.Network;
+import org.qortal.network.Peer;
+import org.qortal.network.message.*;
+
+import java.security.SecureRandom;
+import java.util.*;
+
+import static org.qortal.network.message.MessageType.*;
+
+public class LiteNode {
+
+    private static final Logger LOGGER = LogManager.getLogger(LiteNode.class);
+
+    private static LiteNode instance;
+
+
+    public Map<Integer, Long> pendingRequests = Collections.synchronizedMap(new HashMap<>());
+
+    public int MAX_TRANSACTIONS_PER_MESSAGE = 100;
+
+
+    public LiteNode() {
+
+    }
+
+    public static synchronized LiteNode getInstance() {
+        if (instance == null) {
+            instance = new LiteNode();
+        }
+
+        return instance;
+    }
+
+
+    /**
+     * Fetch account data from peers for given QORT address
+     * @param address - the QORT address to query
+     * @return accountData - the account data for this address, or null if not retrieved
+     */
+    public AccountData fetchAccountData(String address) {
+        GetAccountMessage getAccountMessage = new GetAccountMessage(address);
+        AccountMessage accountMessage = (AccountMessage) this.sendMessage(getAccountMessage, ACCOUNT);
+        if (accountMessage == null) {
+            return null;
+        }
+        return accountMessage.getAccountData();
+    }
+
+    /**
+     * Fetch account balance data from peers for given QORT address and asset ID
+     * @param address - the QORT address to query
+     * @return balance - the balance for this address and assetId, or null if not retrieved
+     */
+    public AccountBalanceData fetchAccountBalance(String address, long assetId) {
+        GetAccountBalanceMessage getAccountMessage = new GetAccountBalanceMessage(address, assetId);
+        AccountBalanceMessage accountMessage = (AccountBalanceMessage) this.sendMessage(getAccountMessage, ACCOUNT_BALANCE);
+        if (accountMessage == null) {
+            return null;
+        }
+        return accountMessage.getAccountBalanceData();
+    }
+
+    /**
+     * Fetch list of transactions for given QORT address
+     * @param address - the QORT address to query
+     * @param limit - the maximum number of results to return
+     * @param offset - the starting index
+     * @return a list of TransactionData objects, or null if not retrieved
+     */
+    public List<TransactionData> fetchAccountTransactions(String address, int limit, int offset) {
+        List<TransactionData> allTransactions = new ArrayList<>();
+        if (limit == 0) {
+            limit = Integer.MAX_VALUE;
+        }
+        int batchSize = Math.min(limit, MAX_TRANSACTIONS_PER_MESSAGE);
+
+        while (allTransactions.size() < limit) {
+            GetAccountTransactionsMessage getAccountTransactionsMessage = new GetAccountTransactionsMessage(address, batchSize, offset);
+            TransactionsMessage transactionsMessage = (TransactionsMessage) this.sendMessage(getAccountTransactionsMessage, TRANSACTIONS);
+            if (transactionsMessage == null) {
+                // An error occurred, so give up instead of returning partial results
+                return null;
+            }
+            allTransactions.addAll(transactionsMessage.getTransactions());
+            if (transactionsMessage.getTransactions().size() < batchSize) {
+                // No more transactions to fetch
+                break;
+            }
+            offset += batchSize;
+        }
+        return allTransactions;
+    }
+
+    /**
+     * Fetch list of names for given QORT address
+     * @param address - the QORT address to query
+     * @return a list of NameData objects, or null if not retrieved
+     */
+    public List<NameData> fetchAccountNames(String address) {
+        GetAccountNamesMessage getAccountNamesMessage = new GetAccountNamesMessage(address);
+        NamesMessage namesMessage = (NamesMessage) this.sendMessage(getAccountNamesMessage, NAMES);
+        if (namesMessage == null) {
+            return null;
+        }
+        return namesMessage.getNameDataList();
+    }
+
+    /**
+     * Fetch info about a registered name
+     * @param name - the name to query
+     * @return a NameData object, or null if not retrieved
+     */
+    public NameData fetchNameData(String name) {
+        GetNameMessage getNameMessage = new GetNameMessage(name);
+        NamesMessage namesMessage = (NamesMessage) this.sendMessage(getNameMessage, NAMES);
+        if (namesMessage == null) {
+            return null;
+        }
+        List<NameData> nameDataList = namesMessage.getNameDataList();
+        if (nameDataList == null || nameDataList.size() != 1) {
+            return null;
+        }
+        // We are only expecting a single item in the list
+        return nameDataList.get(0);
+    }
+
+
+    private Message sendMessage(Message message, MessageType expectedResponseMessageType) {
+        // This asks a random peer for the data
+        // TODO: ask multiple peers, and disregard everything if there are any significant differences in the responses
+
+        // Needs a mutable copy of the unmodifiableList
+        List<Peer> peers = new ArrayList<>(Network.getInstance().getImmutableHandshakedPeers());
+
+        // Disregard peers that have "misbehaved" recently
+        peers.removeIf(Controller.hasMisbehaved);
+
+        // Disregard peers that only have genesis block
+        // TODO: peers.removeIf(Controller.hasOnlyGenesisBlock);
+
+        // Disregard peers that are on an old version
+        peers.removeIf(Controller.hasOldVersion);
+
+        // Disregard peers that are on a known inferior chain tip
+        // TODO: peers.removeIf(Controller.hasInferiorChainTip);
+
+        if (peers.isEmpty()) {
+            LOGGER.info("No peers available to send {} message to", message.getType());
+            return null;
+        }
+
+        // Pick random peer
+        int index = new SecureRandom().nextInt(peers.size());
+        Peer peer = peers.get(index);
+
+        LOGGER.info("Sending {} message to peer {}...", message.getType(), peer);
+
+        Message responseMessage;
+
+        try {
+            responseMessage = peer.getResponse(message);
+
+        } catch (InterruptedException e) {
+            return null;
+        }
+
+        if (responseMessage == null) {
+            LOGGER.info("Peer {} didn't respond to {} message", peer, message.getType());
+            return null;
+        }
+        else if (responseMessage.getType() != expectedResponseMessageType) {
+            LOGGER.info("Peer responded with unexpected message type {} (should be {})", peer, responseMessage.getType(), expectedResponseMessageType);
+            return null;
+        }
+
+        LOGGER.info("Peer {} responded with {} message", peer, responseMessage.getType());
+
+        return responseMessage;
+    }
+
+}

src/main/java/org/qortal/controller/PirateChainWalletController.java

@@ -0,0 +1,404 @@
+package org.qortal.controller;
+
+import com.rust.litewalletjni.LiteWalletJni;
+import org.apache.commons.io.FileUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.qortal.arbitrary.ArbitraryDataFile;
+import org.qortal.arbitrary.ArbitraryDataReader;
+import org.qortal.arbitrary.ArbitraryDataResource;
+import org.qortal.arbitrary.exception.MissingDataException;
+import org.qortal.crosschain.ForeignBlockchainException;
+import org.qortal.crosschain.PirateWallet;
+import org.qortal.data.arbitrary.ArbitraryResourceStatus;
+import org.qortal.data.transaction.ArbitraryTransactionData;
+import org.qortal.data.transaction.TransactionData;
+import org.qortal.network.Network;
+import org.qortal.network.Peer;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.repository.RepositoryManager;
+import org.qortal.settings.Settings;
+import org.qortal.transaction.ArbitraryTransaction;
+import org.qortal.utils.ArbitraryTransactionUtils;
+import org.qortal.utils.Base58;
+import org.qortal.utils.FilesystemUtils;
+import org.qortal.utils.NTP;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.List;
+import java.util.Objects;
+
+public class PirateChainWalletController extends Thread {
+
+    protected static final Logger LOGGER = LogManager.getLogger(PirateChainWalletController.class);
+
+    private static PirateChainWalletController instance;
+
+    final private static long SAVE_INTERVAL = 60 * 60 * 1000L; // 1 hour
+    private long lastSaveTime = 0L;
+
+    private boolean running;
+    private PirateWallet currentWallet = null;
+    private boolean shouldLoadWallet = false;
+    private String loadStatus = null;
+
+    private static String qdnWalletSignature = "EsfUw54perxkEtfoUoL7Z97XPrNsZRZXePVZPz3cwRm9qyEPSofD5KmgVpDqVitQp7LhnZRmL6z2V9hEe1YS45T";
+
+
+    private PirateChainWalletController() {
+        this.running = true;
+    }
+
+    public static PirateChainWalletController getInstance() {
+        if (instance == null)
+            instance = new PirateChainWalletController();
+
+        return instance;
+    }
+
+    @Override
+    public void run() {
+        Thread.currentThread().setName("Pirate Chain Wallet Controller");
+
+        try {
+            while (running && !Controller.isStopping()) {
+                Thread.sleep(1000);
+
+                // Wait until we have a request to load the wallet
+                if (!shouldLoadWallet) {
+                    continue;
+                }
+
+                if (!LiteWalletJni.isLoaded()) {
+                    this.loadLibrary();
+
+                    // If still not loaded, sleep to prevent too many requests
+                    if (!LiteWalletJni.isLoaded()) {
+                        Thread.sleep(5 * 1000);
+                        continue;
+                    }
+                }
+
+                // Wallet is downloaded, so clear the status
+                this.loadStatus = null;
+
+                if (this.currentWallet == null) {
+                    // Nothing to do yet
+                    continue;
+                }
+                if (this.currentWallet.isNullSeedWallet()) {
+                    // Don't sync the null seed wallet
+                    continue;
+                }
+
+                LOGGER.debug("Syncing Pirate Chain wallet...");
+                String response = LiteWalletJni.execute("sync", "");
+                LOGGER.debug("sync response: {}", response);
+
+                try {
+                    JSONObject json = new JSONObject(response);
+                    if (json.has("result")) {
+                        String result = json.getString("result");
+
+                        // We may have to set wallet to ready if this is the first ever successful sync
+                        if (Objects.equals(result, "success")) {
+                            this.currentWallet.setReady(true);
+                        }
+                    }
+                } catch (JSONException e) {
+                    LOGGER.info("Unable to interpret JSON", e);
+                }
+
+                // Rate limit sync attempts
+                Thread.sleep(30000);
+
+                // Save wallet if needed
+                Long now = NTP.getTime();
+                if (now != null && now-SAVE_INTERVAL >= this.lastSaveTime) {
+                    this.saveCurrentWallet();
+                }
+            }
+        } catch (InterruptedException e) {
+            // Fall-through to exit
+        }
+    }
+
+    public void shutdown() {
+        // Save the wallet
+        this.saveCurrentWallet();
+
+        this.running = false;
+        this.interrupt();
+    }
+
+
+    // QDN & wallet libraries
+
+    private void loadLibrary() throws InterruptedException {
+        try (final Repository repository = RepositoryManager.getRepository()) {
+
+            // Check if architecture is supported
+            String libFileName = PirateChainWalletController.getRustLibFilename();
+            if (libFileName == null) {
+                String osName = System.getProperty("os.name");
+                String osArchitecture = System.getProperty("os.arch");
+                this.loadStatus = String.format("Unsupported architecture (%s %s)", osName, osArchitecture);
+                return;
+            }
+
+            // Check if the library exists in the wallets folder
+            Path libDirectory = PirateChainWalletController.getRustLibOuterDirectory();
+            Path libPath = Paths.get(libDirectory.toString(), libFileName);
+            if (Files.exists(libPath)) {
+                // Already downloaded; we can load the library right away
+                LiteWalletJni.loadLibrary();
+                return;
+            }
+
+            // Library not found, so check if we've fetched the resource from QDN
+            ArbitraryTransactionData t = this.getTransactionData(repository);
+            if (t == null) {
+                // Can't find the transaction - maybe on a different chain?
+                return;
+            }
+
+            // Wait until we have a sufficient number of peers to attempt QDN downloads
+            List<Peer> handshakedPeers = Network.getInstance().getImmutableHandshakedPeers();
+            if (handshakedPeers.size() < Settings.getInstance().getMinBlockchainPeers()) {
+                // Wait for more peers
+                this.loadStatus = String.format("Searching for peers...");
+                return;
+            }
+
+            // Build resource
+            ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(t.getName(),
+                    ArbitraryDataFile.ResourceIdType.NAME, t.getService(), t.getIdentifier());
+            try {
+                arbitraryDataReader.loadSynchronously(false);
+            } catch (MissingDataException e) {
+                LOGGER.info("Missing data when loading Pirate Chain library");
+            }
+
+            // Check its status
+            ArbitraryResourceStatus status = ArbitraryTransactionUtils.getStatus(
+                    t.getService(), t.getName(), t.getIdentifier(), false);
+
+            if (status.getStatus() != ArbitraryResourceStatus.Status.READY) {
+                LOGGER.info("Not ready yet: {}", status.getTitle());
+                this.loadStatus = String.format("Downloading files from QDN... (%d / %d)", status.getLocalChunkCount(), status.getTotalChunkCount());
+                return;
+            }
+
+            // Files are downloaded, so copy the necessary files to the wallets folder
+            // Delete the wallets/*/lib directory first, in case earlier versions of the wallet are present
+            Path walletsLibDirectory = PirateChainWalletController.getWalletsLibDirectory();
+            if (Files.exists(walletsLibDirectory)) {
+                FilesystemUtils.safeDeleteDirectory(walletsLibDirectory, false);
+            }
+            Files.createDirectories(libDirectory);
+            FileUtils.copyDirectory(arbitraryDataReader.getFilePath().toFile(), libDirectory.toFile());
+
+            // Clear reader cache so only one copy exists
+            ArbitraryDataResource resource = new ArbitraryDataResource(t.getName(),
+                    ArbitraryDataFile.ResourceIdType.NAME, t.getService(), t.getIdentifier());
+            resource.deleteCache();
+
+            // Finally, load the library
+            LiteWalletJni.loadLibrary();
+
+        } catch (DataException e) {
+            LOGGER.error("Repository issue when loading Pirate Chain library", e);
+        } catch (IOException e) {
+            LOGGER.error("Error when loading Pirate Chain library", e);
+        }
+    }
+
+    private ArbitraryTransactionData getTransactionData(Repository repository) {
+        try {
+            byte[] signature = Base58.decode(qdnWalletSignature);
+            TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
+            if (!(transactionData instanceof ArbitraryTransactionData))
+                return null;
+
+            ArbitraryTransaction arbitraryTransaction = new ArbitraryTransaction(repository, transactionData);
+            if (arbitraryTransaction != null) {
+                return (ArbitraryTransactionData) arbitraryTransaction.getTransactionData();
+            }
+
+            return null;
+        } catch (DataException e) {
+            return null;
+        }
+    }
+
+    public static String getRustLibFilename() {
+        String osName = System.getProperty("os.name");
+        String osArchitecture = System.getProperty("os.arch");
+
+        if (osName.equals("Mac OS X") && osArchitecture.equals("x86_64")) {
+            return "librust-macos-x86_64.dylib";
+        }
+        else if ((osName.equals("Linux") || osName.equals("FreeBSD")) && osArchitecture.equals("aarch64")) {
+            return "librust-linux-aarch64.so";
+        }
+        else if ((osName.equals("Linux") || osName.equals("FreeBSD")) && osArchitecture.equals("amd64")) {
+            return "librust-linux-x86_64.so";
+        }
+        else if (osName.contains("Windows") && osArchitecture.equals("amd64")) {
+            return "librust-windows-x86_64.dll";
+        }
+
+        return null;
+    }
+
+    public static Path getWalletsLibDirectory() {
+        return Paths.get(Settings.getInstance().getWalletsPath(), "PirateChain", "lib");
+    }
+
+    public static Path getRustLibOuterDirectory() {
+        String sigPrefix = qdnWalletSignature.substring(0, 8);
+        return Paths.get(Settings.getInstance().getWalletsPath(), "PirateChain", "lib", sigPrefix);
+    }
+
+
+    // Wallet functions
+
+    public boolean initWithEntropy58(String entropy58) {
+        return this.initWithEntropy58(entropy58, false);
+    }
+
+    public boolean initNullSeedWallet() {
+        return this.initWithEntropy58(Base58.encode(new byte[32]), true);
+    }
+
+    private boolean initWithEntropy58(String entropy58, boolean isNullSeedWallet) {
+        // If the JNI library isn't loaded yet then we can't proceed
+        if (!LiteWalletJni.isLoaded()) {
+            shouldLoadWallet = true;
+            return false;
+        }
+
+        byte[] entropyBytes = Base58.decode(entropy58);
+
+        if (entropyBytes == null || entropyBytes.length != 32) {
+            LOGGER.info("Invalid entropy bytes");
+            return false;
+        }
+
+        if (this.currentWallet != null) {
+            if (this.currentWallet.entropyBytesEqual(entropyBytes)) {
+                // Wallet already active - nothing to do
+                return true;
+            }
+            else {
+                // Different wallet requested - close the existing one and switch over
+                this.closeCurrentWallet();
+            }
+        }
+
+        try {
+            this.currentWallet = new PirateWallet(entropyBytes, isNullSeedWallet);
+            if (!this.currentWallet.isReady()) {
+                // Don't persist wallets that aren't ready
+                this.currentWallet = null;
+            }
+            return true;
+        } catch (IOException e) {
+            LOGGER.info("Unable to initialize wallet: {}", e.getMessage());
+        }
+
+        return false;
+    }
+
+    private void saveCurrentWallet() {
+        if (this.currentWallet == null) {
+            // Nothing to do
+            return;
+        }
+        try {
+            if (this.currentWallet.save()) {
+                Long now = NTP.getTime();
+                if (now != null) {
+                    this.lastSaveTime = now;
+                }
+            }
+        } catch (IOException e) {
+            LOGGER.info("Unable to save wallet");
+        }
+    }
+
+    public PirateWallet getCurrentWallet() {
+        return this.currentWallet;
+    }
+
+    private void closeCurrentWallet() {
+        this.saveCurrentWallet();
+        this.currentWallet = null;
+    }
+
+    public void ensureInitialized() throws ForeignBlockchainException {
+        if (!LiteWalletJni.isLoaded() || this.currentWallet == null || !this.currentWallet.isInitialized()) {
+            throw new ForeignBlockchainException("Pirate wallet isn't initialized yet");
+        }
+    }
+
+    public void ensureNotNullSeed() throws ForeignBlockchainException {
+        // Safety check to make sure funds aren't sent to a null seed wallet
+        if (this.currentWallet == null || this.currentWallet.isNullSeedWallet()) {
+            throw new ForeignBlockchainException("Invalid wallet");
+        }
+    }
+
+    public void ensureSynchronized() throws ForeignBlockchainException {
+        if (this.currentWallet == null || !this.currentWallet.isSynchronized()) {
+            throw new ForeignBlockchainException("Wallet isn't synchronized yet");
+        }
+
+        String response = LiteWalletJni.execute("syncStatus", "");
+        JSONObject json = new JSONObject(response);
+        if (json.has("syncing")) {
+            boolean isSyncing = Boolean.valueOf(json.getString("syncing"));
+            if (isSyncing) {
+                long syncedBlocks = json.getLong("synced_blocks");
+                long totalBlocks = json.getLong("total_blocks");
+
+                throw new ForeignBlockchainException(String.format("Sync in progress (%d / %d). Please try again later.", syncedBlocks, totalBlocks));
+            }
+        }
+    }
+
+    public String getSyncStatus() {
+        if (this.currentWallet == null || !this.currentWallet.isInitialized()) {
+            if (this.loadStatus != null) {
+                return this.loadStatus;
+            }
+
+            return "Not initialized yet";
+        }
+
+        String syncStatusResponse = LiteWalletJni.execute("syncStatus", "");
+        org.json.JSONObject json = new JSONObject(syncStatusResponse);
+        if (json.has("syncing")) {
+            boolean isSyncing = Boolean.valueOf(json.getString("syncing"));
+            if (isSyncing) {
+                long syncedBlocks = json.getLong("synced_blocks");
+                long totalBlocks = json.getLong("total_blocks");
+                return String.format("Sync in progress (%d / %d)", syncedBlocks, totalBlocks);
+            }
+        }
+
+        boolean isSynchronized = this.currentWallet.isSynchronized();
+        if (isSynchronized) {
+            return "Synchronized";
+        }
+
+        return "Initializing wallet...";
+    }
+
+}

src/main/java/org/qortal/controller/Synchronizer.java

@@ -19,21 +19,13 @@ import org.qortal.block.BlockChain;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.block.CommonBlockData;
-import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.transaction.RewardShareTransactionData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.event.Event;
 import org.qortal.event.EventBus;
 import org.qortal.network.Network;
 import org.qortal.network.Peer;
-import org.qortal.network.message.BlockMessage;
-import org.qortal.network.message.BlockSummariesMessage;
-import org.qortal.network.message.GetBlockMessage;
-import org.qortal.network.message.GetBlockSummariesMessage;
-import org.qortal.network.message.GetSignaturesV2Message;
-import org.qortal.network.message.Message;
-import org.qortal.network.message.SignaturesMessage;
-import org.qortal.network.message.Message.MessageType;
+import org.qortal.network.message.*;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
@@ -88,7 +80,7 @@ public class Synchronizer extends Thread {
 	private boolean syncRequestPending = false;
 
 	// Keep track of invalid blocks so that we don't keep trying to sync them
-	private Map<String, Long> invalidBlockSignatures = Collections.synchronizedMap(new HashMap<>());
+	private Map<ByteArray, Long> invalidBlockSignatures = Collections.synchronizedMap(new HashMap<>());
 	public Long timeValidBlockLastReceived = null;
 	public Long timeInvalidBlockLastReceived = null;
 
@@ -134,6 +126,11 @@ public class Synchronizer extends Thread {
 	public void run() {
 		Thread.currentThread().setName("Synchronizer");
 
+		if (Settings.getInstance().isLite()) {
+			// Lite nodes don't need to sync
+			return;
+		}
+
 		try {
 			while (running && !Controller.isStopping()) {
 				Thread.sleep(1000);
@@ -173,8 +170,8 @@ public class Synchronizer extends Thread {
 
 	public Integer getSyncPercent() {
 		synchronized (this.syncLock) {
-			// Report as 100% synced if the latest block is within the last 30 mins
-			final Long minLatestBlockTimestamp = NTP.getTime() - (30 * 60 * 1000L);
+			// Report as 100% synced if the latest block is within the last 60 mins
+			final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
 			if (Controller.getInstance().isUpToDate(minLatestBlockTimestamp)) {
 				return 100;
 			}
@@ -235,9 +232,6 @@ public class Synchronizer extends Thread {
 		// Disregard peers that are on the same block as last sync attempt and we didn't like their chain
 		peers.removeIf(Controller.hasInferiorChainTip);
 
-		// Remove peers with unknown height, lower height or same height and same block signature (unless we don't have their block signature)
-		peers.removeIf(Controller.hasShorterBlockchain);
-
 		final int peersBeforeComparison = peers.size();
 
 		// Request recent block summaries from the remaining peers, and locate our common block with each
@@ -287,7 +281,7 @@ public class Synchronizer extends Thread {
 		BlockData priorChainTip = Controller.getInstance().getChainTip();
 
 		synchronized (this.syncLock) {
-			this.syncPercent = (priorChainTip.getHeight() * 100) / peer.getChainTipData().getLastHeight();
+			this.syncPercent = (priorChainTip.getHeight() * 100) / peer.getChainTipData().getHeight();
 
 			// Only update SysTray if we're potentially changing height
 			if (this.syncPercent < 100) {
@@ -317,7 +311,7 @@ public class Synchronizer extends Thread {
 
 				case INFERIOR_CHAIN: {
 					// Update our list of inferior chain tips
-					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getLastBlockSignature());
+					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getSignature());
 					if (!inferiorChainSignatures.contains(inferiorChainSignature))
 						inferiorChainSignatures.add(inferiorChainSignature);
 
@@ -325,7 +319,8 @@ public class Synchronizer extends Thread {
 					LOGGER.debug(() -> String.format("Refused to synchronize with peer %s (%s)", peer, syncResult.name()));
 
 					// Notify peer of our superior chain
-					if (!peer.sendMessage(Network.getInstance().buildHeightMessage(peer, priorChainTip)))
+					Message message = Network.getInstance().buildHeightOrChainTipInfo(peer);
+					if (message == null || !peer.sendMessage(message))
 						peer.disconnect("failed to notify peer of our superior chain");
 					break;
 				}
@@ -346,7 +341,7 @@ public class Synchronizer extends Thread {
 					// fall-through...
 				case NOTHING_TO_DO: {
 					// Update our list of inferior chain tips
-					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getLastBlockSignature());
+					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getSignature());
 					if (!inferiorChainSignatures.contains(inferiorChainSignature))
 						inferiorChainSignatures.add(inferiorChainSignature);
 
@@ -374,8 +369,7 @@ public class Synchronizer extends Thread {
 				// Reset our cache of inferior chains
 				inferiorChainSignatures.clear();
 
-				Network network = Network.getInstance();
-				network.broadcast(broadcastPeer -> network.buildHeightMessage(broadcastPeer, newChainTip));
+				Network.getInstance().broadcastOurChain();
 
 				EventBus.INSTANCE.notify(new NewChainTipEvent(priorChainTip, newChainTip));
 			}
@@ -518,13 +512,13 @@ public class Synchronizer extends Thread {
 			final BlockData ourLatestBlockData = repository.getBlockRepository().getLastBlock();
 			final int ourInitialHeight = ourLatestBlockData.getHeight();
 
-			PeerChainTipData peerChainTipData = peer.getChainTipData();
-			int peerHeight = peerChainTipData.getLastHeight();
-			byte[] peersLastBlockSignature = peerChainTipData.getLastBlockSignature();
+			BlockSummaryData peerChainTipData = peer.getChainTipData();
+			int peerHeight = peerChainTipData.getHeight();
+			byte[] peersLastBlockSignature = peerChainTipData.getSignature();
 
 			byte[] ourLastBlockSignature = ourLatestBlockData.getSignature();
 			LOGGER.debug(String.format("Fetching summaries from peer %s at height %d, sig %.8s, ts %d; our height %d, sig %.8s, ts %d", peer,
-					peerHeight, Base58.encode(peersLastBlockSignature), peer.getChainTipData().getLastBlockTimestamp(),
+					peerHeight, Base58.encode(peersLastBlockSignature), peerChainTipData.getTimestamp(),
 					ourInitialHeight, Base58.encode(ourLastBlockSignature), ourLatestBlockData.getTimestamp()));
 
 			List<BlockSummaryData> peerBlockSummaries = new ArrayList<>();
@@ -622,7 +616,7 @@ public class Synchronizer extends Thread {
 							// We have already determined that the correct chain diverged from a lower height. We are safe to skip these peers.
 							for (Peer peer : peersSharingCommonBlock) {
 								LOGGER.debug(String.format("Peer %s has common block at height %d but the superior chain is at height %d. Removing it from this round.", peer, commonBlockSummary.getHeight(), dropPeersAfterCommonBlockHeight));
-								this.addInferiorChainSignature(peer.getChainTipData().getLastBlockSignature());
+								//this.addInferiorChainSignature(peer.getChainTipData().getLastBlockSignature());
 							}
 							continue;
 						}
@@ -633,16 +627,18 @@ public class Synchronizer extends Thread {
 					int minChainLength = this.calculateMinChainLengthOfPeers(peersSharingCommonBlock, commonBlockSummary);
 
 					// Fetch block summaries from each peer
-					for (Peer peer : peersSharingCommonBlock) {
+					Iterator peersSharingCommonBlockIterator = peersSharingCommonBlock.iterator();
+					while (peersSharingCommonBlockIterator.hasNext()) {
+						Peer peer = (Peer) peersSharingCommonBlockIterator.next();
 
 						// If we're shutting down, just return the latest peer list
 						if (Controller.isStopping())
 							return peers;
 
 						// Count the number of blocks this peer has beyond our common block
-						final PeerChainTipData peerChainTipData = peer.getChainTipData();
-						final int peerHeight = peerChainTipData.getLastHeight();
-						final byte[] peerLastBlockSignature = peerChainTipData.getLastBlockSignature();
+						final BlockSummaryData peerChainTipData = peer.getChainTipData();
+						final int peerHeight = peerChainTipData.getHeight();
+						final byte[] peerLastBlockSignature = peerChainTipData.getSignature();
 						final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 						// Limit the number of blocks we are comparing. FUTURE: we could request more in batches, but there may not be a case when this is needed
 						int summariesRequired = Math.min(peerAdditionalBlocksAfterCommonBlock, MAXIMUM_REQUEST_SIZE);
@@ -690,6 +686,8 @@ public class Synchronizer extends Thread {
 						if (this.containsInvalidBlockSummary(peer.getCommonBlockData().getBlockSummariesAfterCommonBlock())) {
 							LOGGER.debug("Ignoring peer %s because it holds an invalid block", peer);
 							peers.remove(peer);
+							peersSharingCommonBlockIterator.remove();
+							continue;
 						}
 
 						// Reduce minChainLength if needed. If we don't have any blocks, this peer will be excluded from chain weight comparisons later in the process, so we shouldn't update minChainLength
@@ -728,8 +726,9 @@ public class Synchronizer extends Thread {
 
 					LOGGER.debug(String.format("Listing peers with common block %.8s...", Base58.encode(commonBlockSummary.getSignature())));
 					for (Peer peer : peersSharingCommonBlock) {
-						final int peerHeight = peer.getChainTipData().getLastHeight();
-						final Long peerLastBlockTimestamp = peer.getChainTipData().getLastBlockTimestamp();
+						BlockSummaryData peerChainTipData = peer.getChainTipData();
+						final int peerHeight = peerChainTipData.getHeight();
+						final Long peerLastBlockTimestamp = peerChainTipData.getTimestamp();
 						final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 						final CommonBlockData peerCommonBlockData = peer.getCommonBlockData();
 
@@ -826,7 +825,7 @@ public class Synchronizer extends Thread {
 		// Calculate the length of the shortest peer chain sharing this common block
 		int minChainLength = 0;
 		for (Peer peer : peersSharingCommonBlock) {
-			final int peerHeight = peer.getChainTipData().getLastHeight();
+			final int peerHeight = peer.getChainTipData().getHeight();
 			final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 
 			if (peerAdditionalBlocksAfterCommonBlock < minChainLength || minChainLength == 0)
@@ -845,6 +844,10 @@ public class Synchronizer extends Thread {
 
 	/* Invalid block signature tracking */
 
+	public Map<ByteArray, Long> getInvalidBlockSignatures() {
+		return this.invalidBlockSignatures;
+	}
+
 	private void addInvalidBlockSignature(byte[] signature) {
 		Long now = NTP.getTime();
 		if (now == null) {
@@ -852,8 +855,7 @@ public class Synchronizer extends Thread {
 		}
 
 		// Add or update existing entry
-		String sig58 = Base58.encode(signature);
-		invalidBlockSignatures.put(sig58, now);
+		invalidBlockSignatures.put(ByteArray.wrap(signature), now);
 	}
 	private void deleteOlderInvalidSignatures(Long now) {
 		if (now == null) {
@@ -872,17 +874,16 @@ public class Synchronizer extends Thread {
 			}
 		}
 	}
-	private boolean containsInvalidBlockSummary(List<BlockSummaryData> blockSummaries) {
+	public boolean containsInvalidBlockSummary(List<BlockSummaryData> blockSummaries) {
 		if (blockSummaries == null || invalidBlockSignatures == null) {
 			return false;
 		}
 
 		// Loop through our known invalid blocks and check each one against supplied block summaries
-		for (String invalidSignature58 : invalidBlockSignatures.keySet()) {
-			byte[] invalidSignature = Base58.decode(invalidSignature58);
+		for (ByteArray invalidSignature : invalidBlockSignatures.keySet()) {
 			for (BlockSummaryData blockSummary : blockSummaries) {
 				byte[] signature = blockSummary.getSignature();
-				if (Arrays.equals(signature, invalidSignature)) {
+				if (Arrays.equals(signature, invalidSignature.value)) {
 					return true;
 				}
 			}
@@ -895,10 +896,9 @@ public class Synchronizer extends Thread {
 		}
 
 		// Loop through our known invalid blocks and check each one against supplied block signatures
-		for (String invalidSignature58 : invalidBlockSignatures.keySet()) {
-			byte[] invalidSignature = Base58.decode(invalidSignature58);
+		for (ByteArray invalidSignature : invalidBlockSignatures.keySet()) {
 			for (byte[] signature : blockSignatures) {
-				if (Arrays.equals(signature, invalidSignature)) {
+				if (Arrays.equals(signature, invalidSignature.value)) {
 					return true;
 				}
 			}
@@ -933,13 +933,13 @@ public class Synchronizer extends Thread {
 					final BlockData ourLatestBlockData = repository.getBlockRepository().getLastBlock();
 					final int ourInitialHeight = ourLatestBlockData.getHeight();
 
-					PeerChainTipData peerChainTipData = peer.getChainTipData();
-					int peerHeight = peerChainTipData.getLastHeight();
-					byte[] peersLastBlockSignature = peerChainTipData.getLastBlockSignature();
+					BlockSummaryData peerChainTipData = peer.getChainTipData();
+					int peerHeight = peerChainTipData.getHeight();
+					byte[] peersLastBlockSignature = peerChainTipData.getSignature();
 
 					byte[] ourLastBlockSignature = ourLatestBlockData.getSignature();
 					String syncString = String.format("Synchronizing with peer %s at height %d, sig %.8s, ts %d; our height %d, sig %.8s, ts %d", peer,
-							peerHeight, Base58.encode(peersLastBlockSignature), peer.getChainTipData().getLastBlockTimestamp(),
+							peerHeight, Base58.encode(peersLastBlockSignature), peerChainTipData.getTimestamp(),
 							ourInitialHeight, Base58.encode(ourLastBlockSignature), ourLatestBlockData.getTimestamp());
 					LOGGER.info(syncString);
 
@@ -1246,7 +1246,14 @@ public class Synchronizer extends Thread {
 		int numberSignaturesRequired = additionalPeerBlocksAfterCommonBlock - peerBlockSignatures.size();
 
 		int retryCount = 0;
-		while (height < peerHeight) {
+
+		// Keep fetching blocks from peer until we reach their tip, or reach a count of MAXIMUM_COMMON_DELTA blocks.
+		// We need to limit the total number, otherwise too much can be loaded into memory, causing an
+		// OutOfMemoryException. This is common when syncing from 1000+ blocks behind the chain tip, after starting
+		// from a small fork that didn't become part of the main chain. This causes the entire sync process to
+		// use syncToPeerChain(), resulting in potentially thousands of blocks being held in memory if the limit
+		// below isn't applied.
+		while (height < peerHeight && peerBlocks.size() <= MAXIMUM_COMMON_DELTA) {
 			if (Controller.isStopping())
 				return SynchronizationResult.SHUTTING_DOWN;
 
@@ -1313,7 +1320,7 @@ public class Synchronizer extends Thread {
 			// Final check to make sure the peer isn't out of date (except for when we're in recovery mode)
 			if (!recoveryMode && peer.getChainTipData() != null) {
 				final Long minLatestBlockTimestamp = Controller.getMinimumLatestBlockTimestamp();
-				final Long peerLastBlockTimestamp = peer.getChainTipData().getLastBlockTimestamp();
+				final Long peerLastBlockTimestamp = peer.getChainTipData().getTimestamp();
 				if (peerLastBlockTimestamp == null || peerLastBlockTimestamp < minLatestBlockTimestamp) {
 					LOGGER.info(String.format("Peer %s is out of date, so abandoning sync attempt", peer));
 					return SynchronizationResult.CHAIN_TIP_TOO_OLD;
@@ -1553,12 +1560,19 @@ public class Synchronizer extends Thread {
 		Message getBlockSummariesMessage = new GetBlockSummariesMessage(parentSignature, numberRequested);
 
 		Message message = peer.getResponse(getBlockSummariesMessage);
-		if (message == null || message.getType() != MessageType.BLOCK_SUMMARIES)
+		if (message == null)
 			return null;
 
-		BlockSummariesMessage blockSummariesMessage = (BlockSummariesMessage) message;
+		if (message.getType() == MessageType.BLOCK_SUMMARIES) {
+			BlockSummariesMessage blockSummariesMessage = (BlockSummariesMessage) message;
+			return blockSummariesMessage.getBlockSummaries();
+		}
+		else if (message.getType() == MessageType.BLOCK_SUMMARIES_V2) {
+			BlockSummariesV2Message blockSummariesMessage = (BlockSummariesV2Message) message;
+			return blockSummariesMessage.getBlockSummaries();
+		}
 
-		return blockSummariesMessage.getBlockSummaries();
+		return null;
 	}
 
 	private List<byte[]> getBlockSignatures(Peer peer, byte[] parentSignature, int numberRequested) throws InterruptedException {
@@ -1577,12 +1591,23 @@ public class Synchronizer extends Thread {
 		Message getBlockMessage = new GetBlockMessage(signature);
 
 		Message message = peer.getResponse(getBlockMessage);
-		if (message == null || message.getType() != MessageType.BLOCK)
+		if (message == null)
 			return null;
 
-		BlockMessage blockMessage = (BlockMessage) message;
+		switch (message.getType()) {
+			case BLOCK: {
+				BlockMessage blockMessage = (BlockMessage) message;
+				return new Block(repository, blockMessage.getBlockData(), blockMessage.getTransactions(), blockMessage.getAtStates());
+			}
 
-		return new Block(repository, blockMessage.getBlockData(), blockMessage.getTransactions(), blockMessage.getAtStates());
+			case BLOCK_V2: {
+				BlockV2Message blockMessage = (BlockV2Message) message;
+				return new Block(repository, blockMessage.getBlockData(), blockMessage.getTransactions(), blockMessage.getAtStatesHash());
+			}
+
+			default:
+				return null;
+		}
 	}
 
 	public void populateBlockSummariesMinterLevels(Repository repository, List<BlockSummaryData> blockSummaries) throws DataException {

src/main/java/org/qortal/controller/TransactionImporter.java

@@ -2,7 +2,9 @@ package org.qortal.controller;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.qortal.data.block.BlockData;
 import org.qortal.data.transaction.TransactionData;
+import org.qortal.network.Network;
 import org.qortal.network.Peer;
 import org.qortal.network.message.GetTransactionMessage;
 import org.qortal.network.message.Message;
@@ -11,13 +13,15 @@ import org.qortal.network.message.TransactionSignaturesMessage;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
+import org.qortal.settings.Settings;
 import org.qortal.transaction.Transaction;
+import org.qortal.transform.TransformationException;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 
 import java.util.*;
-import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReentrantLock;
+import java.util.stream.Collectors;
 
 public class TransactionImporter extends Thread {
 
@@ -54,12 +58,16 @@ public class TransactionImporter extends Thread {
 
     @Override
     public void run() {
+        Thread.currentThread().setName("Transaction Importer");
+
         try {
             while (!Controller.isStopping()) {
-                Thread.sleep(1000L);
+                Thread.sleep(500L);
 
                 // Process incoming transactions queue
-                processIncomingTransactionsQueue();
+                validateTransactionsInQueue();
+                importTransactionsInQueue();
+
                 // Clean up invalid incoming transactions list
                 cleanupInvalidTransactionsList(NTP.getTime());
             }
@@ -86,7 +94,26 @@ public class TransactionImporter extends Thread {
         incomingTransactions.keySet().removeIf(t -> Arrays.equals(t.getSignature(), signature));
     }
 
-    private void processIncomingTransactionsQueue() {
+    /**
+     * Retrieve all pending unconfirmed transactions that have had their signatures validated.
+     * @return a list of TransactionData objects, with valid signatures.
+     */
+    private List<TransactionData> getCachedSigValidTransactions() {
+        synchronized (this.incomingTransactions) {
+            return this.incomingTransactions.entrySet().stream()
+                    .filter(t -> Boolean.TRUE.equals(t.getValue()))
+                    .map(Map.Entry::getKey)
+                    .collect(Collectors.toList());
+        }
+    }
+
+    /**
+     * Validate the signatures of any transactions pending import, then update their
+     * entries in the queue to mark them as valid/invalid.
+     *
+     * No database lock is required.
+     */
+    private void validateTransactionsInQueue() {
         if (this.incomingTransactions.isEmpty()) {
             // Nothing to do?
             return;
@@ -103,8 +130,17 @@ public class TransactionImporter extends Thread {
                 LOGGER.debug("Validating signatures in incoming transactions queue (size {})...", unvalidatedCount);
             }
 
+            // A list of all currently pending transactions that have valid signatures
             List<Transaction> sigValidTransactions = new ArrayList<>();
 
+            // A list of signatures that became valid in this round
+            List<byte[]> newlyValidSignatures = new ArrayList<>();
+
+            boolean isLiteNode = Settings.getInstance().isLite();
+
+            // We need the latest block in order to check for expired transactions
+            BlockData latestBlock = Controller.getInstance().getChainTip();
+
             // Signature validation round - does not require blockchain lock
             for (Map.Entry<TransactionData, Boolean> transactionEntry : incomingTransactionsCopy.entrySet()) {
                 // Quick exit?
@@ -114,34 +150,59 @@ public class TransactionImporter extends Thread {
 
                 TransactionData transactionData = transactionEntry.getKey();
                 Transaction transaction = Transaction.fromData(repository, transactionData);
+                String signature58 = Base58.encode(transactionData.getSignature());
+
+                Long now = NTP.getTime();
+                if (now == null) {
+                    return;
+                }
+
+                // Drop expired transactions before they are considered "sig valid"
+                if (latestBlock != null && transaction.getDeadline() <= latestBlock.getTimestamp()) {
+                    LOGGER.debug("Removing expired {} transaction {} from import queue", transactionData.getType().name(), signature58);
+                    removeIncomingTransaction(transactionData.getSignature());
+                    invalidUnconfirmedTransactions.put(signature58, (now + EXPIRED_TRANSACTION_RECHECK_INTERVAL));
+                    continue;
+                }
 
                 // Only validate signature if we haven't already done so
                 Boolean isSigValid = transactionEntry.getValue();
                 if (!Boolean.TRUE.equals(isSigValid)) {
-                    if (!transaction.isSignatureValid()) {
-                        String signature58 = Base58.encode(transactionData.getSignature());
+                    if (isLiteNode) {
+                        // Lite nodes can't easily validate transactions, so for now we will have to assume that everything is valid
+                        sigValidTransactions.add(transaction);
+                        newlyValidSignatures.add(transactionData.getSignature());
+                        // Add mark signature as valid if transaction still exists in import queue
+                        incomingTransactions.computeIfPresent(transactionData, (k, v) -> Boolean.TRUE);
+                        continue;
+                    }
 
-                        LOGGER.trace("Ignoring {} transaction {} with invalid signature", transactionData.getType().name(), signature58);
+                    if (!transaction.isSignatureValid()) {
+                        LOGGER.debug("Ignoring {} transaction {} with invalid signature", transactionData.getType().name(), signature58);
                         removeIncomingTransaction(transactionData.getSignature());
 
                         // Also add to invalidIncomingTransactions map
-                        Long now = NTP.getTime();
+                        now = NTP.getTime();
                         if (now != null) {
                             Long expiry = now + INVALID_TRANSACTION_RECHECK_INTERVAL;
-                            LOGGER.trace("Adding stale invalid transaction {} to invalidUnconfirmedTransactions...", signature58);
+                            LOGGER.trace("Adding invalid transaction {} to invalidUnconfirmedTransactions...", signature58);
                             // Add to invalidUnconfirmedTransactions so that we don't keep requesting it
                             invalidUnconfirmedTransactions.put(signature58, expiry);
                         }
 
+                        // We're done with this transaction
                         continue;
                     }
-                    else {
-                        // Count the number that were validated in this round, for logging purposes
-                        validatedCount++;
-                    }
+
+                    // Count the number that were validated in this round, for logging purposes
+                    validatedCount++;
 
                     // Add mark signature as valid if transaction still exists in import queue
                     incomingTransactions.computeIfPresent(transactionData, (k, v) -> Boolean.TRUE);
+
+                    // Signature validated in this round
+                    newlyValidSignatures.add(transactionData.getSignature());
+
                 } else {
                     LOGGER.trace(() -> String.format("Transaction %s known to have valid signature", Base58.encode(transactionData.getSignature())));
                 }
@@ -154,30 +215,44 @@ public class TransactionImporter extends Thread {
                 LOGGER.debug("Finished validating signatures in incoming transactions queue (valid this round: {}, total pending import: {})...", validatedCount, sigValidTransactions.size());
             }
 
-            if (sigValidTransactions.isEmpty()) {
-                // Don't bother locking if there are no new transactions to process
-                return;
+            if (!newlyValidSignatures.isEmpty()) {
+                LOGGER.debug("Broadcasting {} newly valid signatures ahead of import", newlyValidSignatures.size());
+                Message newTransactionSignatureMessage = new TransactionSignaturesMessage(newlyValidSignatures);
+                Network.getInstance().broadcast(broadcastPeer -> newTransactionSignatureMessage);
             }
 
-            if (Synchronizer.getInstance().isSyncRequested() || Synchronizer.getInstance().isSynchronizing()) {
-                // Prioritize syncing, and don't attempt to lock
-                // Signature validity is retained in the incomingTransactions map, to avoid the above work being wasted
-                return;
-            }
+        } catch (DataException e) {
+            LOGGER.error("Repository issue while processing incoming transactions", e);
+        }
+    }
 
-            try {
-                ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
-                if (!blockchainLock.tryLock(2, TimeUnit.SECONDS)) {
-                    // Signature validity is retained in the incomingTransactions map, to avoid the above work being wasted
-                    LOGGER.debug("Too busy to process incoming transactions queue");
-                    return;
-                }
-            } catch (InterruptedException e) {
-                LOGGER.debug("Interrupted when trying to acquire blockchain lock");
-                return;
-            }
+    /**
+     * Import any transactions in the queue that have valid signatures.
+     *
+     * A database lock is required.
+     */
+    private void importTransactionsInQueue() {
+        List<TransactionData> sigValidTransactions = this.getCachedSigValidTransactions();
+        if (sigValidTransactions.isEmpty()) {
+            // Don't bother locking if there are no new transactions to process
+            return;
+        }
 
-            LOGGER.debug("Processing incoming transactions queue (size {})...", sigValidTransactions.size());
+        if (Synchronizer.getInstance().isSyncRequested() || Synchronizer.getInstance().isSynchronizing()) {
+            // Prioritize syncing, and don't attempt to lock
+            return;
+        }
+
+        ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+        if (!blockchainLock.tryLock()) {
+            LOGGER.debug("Too busy to import incoming transactions queue");
+            return;
+        }
+
+        LOGGER.debug("Importing incoming transactions queue (size {})...", sigValidTransactions.size());
+
+        int processedCount = 0;
+        try (final Repository repository = RepositoryManager.getRepository()) {
 
             // Import transactions with valid signatures
             try {
@@ -187,14 +262,15 @@ public class TransactionImporter extends Thread {
                     }
 
                     if (Synchronizer.getInstance().isSyncRequestPending()) {
-                        LOGGER.debug("Breaking out of transaction processing with {} remaining, because a sync request is pending", sigValidTransactions.size() - i);
+                        LOGGER.debug("Breaking out of transaction importing with {} remaining, because a sync request is pending", sigValidTransactions.size() - i);
                         return;
                     }
 
-                    Transaction transaction = sigValidTransactions.get(i);
-                    TransactionData transactionData = transaction.getTransactionData();
+                    TransactionData transactionData = sigValidTransactions.get(i);
+                    Transaction transaction = Transaction.fromData(repository, transactionData);
 
                     Transaction.ValidationResult validationResult = transaction.importAsUnconfirmed();
+                    processedCount++;
 
                     switch (validationResult) {
                         case TRANSACTION_ALREADY_EXISTS: {
@@ -216,7 +292,7 @@ public class TransactionImporter extends Thread {
                         // All other invalid cases:
                         default: {
                             final String signature58 = Base58.encode(transactionData.getSignature());
-                            LOGGER.trace(() -> String.format("Ignoring invalid (%s) %s transaction %s", validationResult.name(), transactionData.getType().name(), signature58));
+                            LOGGER.debug(() -> String.format("Ignoring invalid (%s) %s transaction %s", validationResult.name(), transactionData.getType().name(), signature58));
 
                             Long now = NTP.getTime();
                             if (now != null && now - transactionData.getTimestamp() > INVALID_TRANSACTION_STALE_TIMEOUT) {
@@ -239,12 +315,11 @@ public class TransactionImporter extends Thread {
                     removeIncomingTransaction(transactionData.getSignature());
                 }
             } finally {
-                LOGGER.debug("Finished processing incoming transactions queue");
-                ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+                LOGGER.debug("Finished importing {} incoming transaction{}", processedCount, (processedCount == 1 ? "" : "s"));
                 blockchainLock.unlock();
             }
         } catch (DataException e) {
-            LOGGER.error("Repository issue while processing incoming transactions", e);
+            LOGGER.error("Repository issue while importing incoming transactions", e);
         }
     }
 
@@ -277,8 +352,18 @@ public class TransactionImporter extends Thread {
         byte[] signature = getTransactionMessage.getSignature();
 
         try (final Repository repository = RepositoryManager.getRepository()) {
-            TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
+            // Firstly check the sig-valid transactions that are currently queued for import
+            TransactionData transactionData = this.getCachedSigValidTransactions().stream()
+                    .filter(t -> Arrays.equals(signature, t.getSignature()))
+                    .findFirst().orElse(null);
+
             if (transactionData == null) {
+                // Not found in import queue, so try the database
+                transactionData = repository.getTransactionRepository().fromSignature(signature);
+            }
+
+            if (transactionData == null) {
+                // Still not found - so we don't have this transaction
                 LOGGER.debug(() -> String.format("Ignoring GET_TRANSACTION request from peer %s for unknown transaction %s", peer, Base58.encode(signature)));
                 // Send no response at all???
                 return;
@@ -289,7 +374,9 @@ public class TransactionImporter extends Thread {
             if (!peer.sendMessage(transactionMessage))
                 peer.disconnect("failed to send transaction");
         } catch (DataException e) {
-            LOGGER.error(String.format("Repository issue while send transaction %s to peer %s", Base58.encode(signature), peer), e);
+            LOGGER.error(String.format("Repository issue while sending transaction %s to peer %s", Base58.encode(signature), peer), e);
+        } catch (TransformationException e) {
+            LOGGER.error(String.format("Serialization issue while sending transaction %s to peer %s", Base58.encode(signature), peer), e);
         }
     }
 

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataFileListManager.java

@@ -67,6 +67,9 @@ public class ArbitraryDataFileListManager {
     /** Maximum number of hops that a file list relay request is allowed to make */
     public static int RELAY_REQUEST_MAX_HOPS = 4;
 
+    /** Minimum peer version to use relay */
+    public static String RELAY_MIN_PEER_VERSION = "3.4.0";
+
 
     private ArbitraryDataFileListManager() {
     }
@@ -120,12 +123,22 @@ public class ArbitraryDataFileListManager {
             }
         }
 
-        // Then allow another 5 attempts, each 5 minutes apart
+        // Then allow another 3 attempts, each 5 minutes apart
         if (timeSinceLastAttempt > 5 * 60 * 1000L) {
             // We haven't tried for at least 5 minutes
 
-            if (networkBroadcastCount < 5) {
-                // We've made less than 5 total attempts
+            if (networkBroadcastCount < 6) {
+                // We've made less than 6 total attempts
+                return true;
+            }
+        }
+
+        // Then allow another 4 attempts, each 30 minutes apart
+        if (timeSinceLastAttempt > 30 * 60 * 1000L) {
+            // We haven't tried for at least 5 minutes
+
+            if (networkBroadcastCount < 10) {
+                // We've made less than 10 total attempts
                 return true;
             }
         }
@@ -184,8 +197,8 @@ public class ArbitraryDataFileListManager {
             }
         }
 
-        if (timeSinceLastAttempt > 24 * 60 * 60 * 1000L) {
-            // We haven't tried for at least 24 hours
+        if (timeSinceLastAttempt > 60 * 60 * 1000L) {
+            // We haven't tried for at least 1 hour
             return true;
         }
 
@@ -283,8 +296,8 @@ public class ArbitraryDataFileListManager {
 
         LOGGER.debug(String.format("Sending data file list request for signature %s with %d hashes to %d peers...", signature58, hashCount, handshakedPeers.size()));
 
-        // FUTURE: send our address as requestingPeer once enough peers have switched to the new protocol
-        String requestingPeer = null; // Network.getInstance().getOurExternalIpAddressAndPort();
+        // Send our address as requestingPeer, to allow for potential direct connections with seeds/peers
+        String requestingPeer = Network.getInstance().getOurExternalIpAddressAndPort();
 
         // Build request
         Message getArbitraryDataFileListMessage = new GetArbitraryDataFileListMessage(signature, missingHashes, now, 0, requestingPeer);
@@ -511,18 +524,24 @@ public class ArbitraryDataFileListManager {
 
                     // Bump requestHops if it exists
                     if (requestHops != null) {
-                        arbitraryDataFileListMessage.setRequestHops(++requestHops);
+                        requestHops++;
                     }
 
+                    ArbitraryDataFileListMessage forwardArbitraryDataFileListMessage;
+
                     // Remove optional parameters if the requesting peer doesn't support it yet
                     // A message with less statistical data is better than no message at all
                     if (!requestingPeer.isAtLeastVersion(MIN_PEER_VERSION_FOR_FILE_LIST_STATS)) {
-                        arbitraryDataFileListMessage.removeOptionalStats();
+                        forwardArbitraryDataFileListMessage = new ArbitraryDataFileListMessage(signature, hashes);
+                    } else {
+                        forwardArbitraryDataFileListMessage = new ArbitraryDataFileListMessage(signature, hashes, requestTime, requestHops,
+                                arbitraryDataFileListMessage.getPeerAddress(), arbitraryDataFileListMessage.isRelayPossible());
                     }
+                    forwardArbitraryDataFileListMessage.setId(message.getId());
 
                     // Forward to requesting peer
                     LOGGER.debug("Forwarding file list with {} hashes to requesting peer: {}", hashes.size(), requestingPeer);
-                    if (!requestingPeer.sendMessage(arbitraryDataFileListMessage)) {
+                    if (!requestingPeer.sendMessage(forwardArbitraryDataFileListMessage)) {
                         requestingPeer.disconnect("failed to forward arbitrary data file list");
                     }
                 }
@@ -631,6 +650,9 @@ public class ArbitraryDataFileListManager {
         // We should only respond if we have at least one hash
         if (hashes.size() > 0) {
 
+            // Firstly we should keep track of the requesting peer, to allow for potential direct connections later
+            ArbitraryDataFileManager.getInstance().addRecentDataRequest(requestingPeer);
+
             // We have all the chunks, so update requests map to reflect that we've sent it
             // There is no need to keep track of the request, as we can serve all the chunks
             if (allChunksExist) {
@@ -639,16 +661,19 @@ public class ArbitraryDataFileListManager {
             }
 
             String ourAddress = Network.getInstance().getOurExternalIpAddressAndPort();
-            ArbitraryDataFileListMessage arbitraryDataFileListMessage = new ArbitraryDataFileListMessage(signature,
-                    hashes, NTP.getTime(), 0, ourAddress, true);
-            arbitraryDataFileListMessage.setId(message.getId());
+            ArbitraryDataFileListMessage arbitraryDataFileListMessage;
 
             // Remove optional parameters if the requesting peer doesn't support it yet
             // A message with less statistical data is better than no message at all
             if (!peer.isAtLeastVersion(MIN_PEER_VERSION_FOR_FILE_LIST_STATS)) {
-                arbitraryDataFileListMessage.removeOptionalStats();
+                arbitraryDataFileListMessage = new ArbitraryDataFileListMessage(signature, hashes);
+            } else {
+                arbitraryDataFileListMessage = new ArbitraryDataFileListMessage(signature,
+                        hashes, NTP.getTime(), 0, ourAddress, true);
             }
 
+            arbitraryDataFileListMessage.setId(message.getId());
+
             if (!peer.sendMessage(arbitraryDataFileListMessage)) {
                 LOGGER.debug("Couldn't send list of hashes");
                 peer.disconnect("failed to send list of hashes");
@@ -670,8 +695,7 @@ public class ArbitraryDataFileListManager {
             // In relay mode - so ask our other peers if they have it
 
             long requestTime = getArbitraryDataFileListMessage.getRequestTime();
-            int requestHops = getArbitraryDataFileListMessage.getRequestHops();
-            getArbitraryDataFileListMessage.setRequestHops(++requestHops);
+            int requestHops = getArbitraryDataFileListMessage.getRequestHops() + 1;
             long totalRequestTime = now - requestTime;
 
             if (totalRequestTime < RELAY_REQUEST_MAX_DURATION) {
@@ -679,11 +703,15 @@ public class ArbitraryDataFileListManager {
                 if (requestHops < RELAY_REQUEST_MAX_HOPS) {
                     // Relay request hasn't reached the maximum number of hops yet, so can be rebroadcast
 
+                    Message relayGetArbitraryDataFileListMessage = new GetArbitraryDataFileListMessage(signature, hashes, requestTime, requestHops, requestingPeer);
+                    relayGetArbitraryDataFileListMessage.setId(message.getId());
+
                     LOGGER.debug("Rebroadcasting hash list request from peer {} for signature {} to our other peers... totalRequestTime: {}, requestHops: {}", peer, Base58.encode(signature), totalRequestTime, requestHops);
                     Network.getInstance().broadcast(
-                            broadcastPeer -> broadcastPeer == peer ||
-                                    Objects.equals(broadcastPeer.getPeerData().getAddress().getHost(), peer.getPeerData().getAddress().getHost())
-                                    ? null : getArbitraryDataFileListMessage);
+                            broadcastPeer ->
+                                    !broadcastPeer.isAtLeastVersion(RELAY_MIN_PEER_VERSION) ? null :
+                                    broadcastPeer == peer || Objects.equals(broadcastPeer.getPeerData().getAddress().getHost(), peer.getPeerData().getAddress().getHost()) ? null : relayGetArbitraryDataFileListMessage
+                    );
 
                 }
                 else {

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataFileManager.java

@@ -1,5 +1,6 @@
 package org.qortal.controller.arbitrary;
 
+import com.google.common.net.InetAddresses;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.ArbitraryDataFile;
@@ -7,7 +8,6 @@ import org.qortal.controller.Controller;
 import org.qortal.data.arbitrary.ArbitraryDirectConnectionInfo;
 import org.qortal.data.arbitrary.ArbitraryFileListResponseInfo;
 import org.qortal.data.arbitrary.ArbitraryRelayInfo;
-import org.qortal.data.network.ArbitraryPeerData;
 import org.qortal.data.network.PeerData;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.network.Network;
@@ -55,6 +55,13 @@ public class ArbitraryDataFileManager extends Thread {
      */
     private List<ArbitraryDirectConnectionInfo> directConnectionInfo = Collections.synchronizedList(new ArrayList<>());
 
+    /**
+     * Map to keep track of peers requesting QDN data that we hold.
+     * Key = peer address string, value = time of last request.
+     * This allows for additional "burst" connections beyond existing limits.
+     */
+    private Map<String, Long> recentDataRequests = Collections.synchronizedMap(new HashMap<>());
+
 
     public static int MAX_FILE_HASH_RESPONSES = 1000;
 
@@ -109,6 +116,9 @@ public class ArbitraryDataFileManager extends Thread {
 
         final long directConnectionInfoMinimumTimestamp = now - ArbitraryDataManager.getInstance().ARBITRARY_DIRECT_CONNECTION_INFO_TIMEOUT;
         directConnectionInfo.removeIf(entry -> entry.getTimestamp() < directConnectionInfoMinimumTimestamp);
+
+        final long recentDataRequestMinimumTimestamp = now - ArbitraryDataManager.getInstance().ARBITRARY_RECENT_DATA_REQUESTS_TIMEOUT;
+        recentDataRequests.entrySet().removeIf(entry -> entry.getValue() < recentDataRequestMinimumTimestamp);
     }
 
 
@@ -187,7 +197,7 @@ public class ArbitraryDataFileManager extends Thread {
         ArbitraryDataFile existingFile = ArbitraryDataFile.fromHash(hash, signature);
         boolean fileAlreadyExists = existingFile.exists();
         String hash58 = Base58.encode(hash);
-        Message message = null;
+        ArbitraryDataFileMessage arbitraryDataFileMessage;
 
         // Fetch the file if it doesn't exist locally
         if (!fileAlreadyExists) {
@@ -195,10 +205,11 @@ public class ArbitraryDataFileManager extends Thread {
             arbitraryDataFileRequests.put(hash58, NTP.getTime());
             Message getArbitraryDataFileMessage = new GetArbitraryDataFileMessage(signature, hash);
 
+            Message response = null;
             try {
-                message = peer.getResponseWithTimeout(getArbitraryDataFileMessage, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT);
+                response = peer.getResponseWithTimeout(getArbitraryDataFileMessage, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT);
             } catch (InterruptedException e) {
-                // Will return below due to null message
+                // Will return below due to null response
             }
             arbitraryDataFileRequests.remove(hash58);
             LOGGER.trace(String.format("Removed hash %.8s from arbitraryDataFileRequests", hash58));
@@ -206,22 +217,24 @@ public class ArbitraryDataFileManager extends Thread {
             // We may need to remove the file list request, if we have all the files for this transaction
             this.handleFileListRequests(signature);
 
-            if (message == null) {
-                LOGGER.debug("Received null message from peer {}", peer);
+            if (response == null) {
+                LOGGER.debug("Received null response from peer {}", peer);
                 return null;
             }
-            if (message.getType() != Message.MessageType.ARBITRARY_DATA_FILE) {
-                LOGGER.debug("Received message with invalid type: {} from peer {}", message.getType(), peer);
+            if (response.getType() != MessageType.ARBITRARY_DATA_FILE) {
+                LOGGER.debug("Received response with invalid type: {} from peer {}", response.getType(), peer);
                 return null;
             }
-        }
-        else {
+
+            ArbitraryDataFileMessage peersArbitraryDataFileMessage = (ArbitraryDataFileMessage) response;
+            arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, peersArbitraryDataFileMessage.getArbitraryDataFile());
+        } else {
             LOGGER.debug(String.format("File hash %s already exists, so skipping the request", hash58));
+            arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, existingFile);
         }
-        ArbitraryDataFileMessage arbitraryDataFileMessage = (ArbitraryDataFileMessage) message;
 
         // We might want to forward the request to the peer that originally requested it
-        this.handleArbitraryDataFileForwarding(requestingPeer, message, originalMessage);
+        this.handleArbitraryDataFileForwarding(requestingPeer, arbitraryDataFileMessage, originalMessage);
 
         boolean isRelayRequest = (requestingPeer != null);
         if (isRelayRequest) {
@@ -488,6 +501,45 @@ public class ArbitraryDataFileManager extends Thread {
     }
 
 
+    // Peers requesting QDN data from us
+
+    /**
+     * Add an address string of a peer that is trying to request data from us.
+     * @param peerAddress
+     */
+    public void addRecentDataRequest(String peerAddress) {
+        if (peerAddress == null) {
+            return;
+        }
+
+        Long now = NTP.getTime();
+        if (now == null) {
+            return;
+        }
+
+        // Make sure to remove the port, since it isn't guaranteed to match next time
+        String[] parts = peerAddress.split(":");
+        if (parts.length == 0) {
+            return;
+        }
+        String host = parts[0];
+        if (!InetAddresses.isInetAddress(host)) {
+            // Invalid host
+            return;
+        }
+
+        this.recentDataRequests.put(host, now);
+    }
+
+    public boolean isPeerRequestingData(String peerAddressWithoutPort) {
+        return this.recentDataRequests.containsKey(peerAddressWithoutPort);
+    }
+
+    public boolean hasPendingDataRequest() {
+        return !this.recentDataRequests.isEmpty();
+    }
+
+
     // Network handlers
 
     public void onNetworkGetArbitraryDataFileMessage(Peer peer, Message message) {
@@ -543,9 +595,10 @@ public class ArbitraryDataFileManager extends Thread {
                 // Send valid, yet unexpected message type in response, so peer's synchronizer doesn't have to wait for timeout
                 LOGGER.debug(String.format("Sending 'file unknown' response to peer %s for GET_FILE request for unknown file %s", peer, arbitraryDataFile));
 
-                // We'll send empty block summaries message as it's very short
-                // TODO: use a different message type here
-                Message fileUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+                // Send generic 'unknown' message as it's very short
+                Message fileUnknownMessage = peer.getPeersVersion() >= GenericUnknownMessage.MINIMUM_PEER_VERSION
+                        ? new GenericUnknownMessage()
+                        : new BlockSummariesMessage(Collections.emptyList());
                 fileUnknownMessage.setId(message.getId());
                 if (!peer.sendMessage(fileUnknownMessage)) {
                     LOGGER.debug("Couldn't sent file-unknown response");

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataManager.java

@@ -47,6 +47,9 @@ public class ArbitraryDataManager extends Thread {
 	/** Maximum time to hold direct peer connection information */
 	public static final long ARBITRARY_DIRECT_CONNECTION_INFO_TIMEOUT = 2 * 60 * 1000L; // ms
 
+	/** Maximum time to hold information about recent data requests that we can fulfil */
+	public static final long ARBITRARY_RECENT_DATA_REQUESTS_TIMEOUT = 2 * 60 * 1000L; // ms
+
 	/** Maximum number of hops that an arbitrary signatures request is allowed to make */
 	private static int ARBITRARY_SIGNATURES_REQUEST_MAX_HOPS = 3;
 

src/main/java/org/qortal/controller/arbitrary/ArbitraryMetadataManager.java

@@ -22,8 +22,7 @@ import org.qortal.utils.Triple;
 import java.io.IOException;
 import java.util.*;
 
-import static org.qortal.controller.arbitrary.ArbitraryDataFileListManager.RELAY_REQUEST_MAX_DURATION;
-import static org.qortal.controller.arbitrary.ArbitraryDataFileListManager.RELAY_REQUEST_MAX_HOPS;
+import static org.qortal.controller.arbitrary.ArbitraryDataFileListManager.*;
 
 public class ArbitraryMetadataManager {
 
@@ -338,9 +337,12 @@ public class ArbitraryMetadataManager {
                 Peer requestingPeer = request.getB();
                 if (requestingPeer != null) {
 
+                    ArbitraryMetadataMessage forwardArbitraryMetadataMessage = new ArbitraryMetadataMessage(signature, arbitraryMetadataMessage.getArbitraryMetadataFile());
+                    forwardArbitraryMetadataMessage.setId(arbitraryMetadataMessage.getId());
+
                     // Forward to requesting peer
                     LOGGER.debug("Forwarding metadata to requesting peer: {}", requestingPeer);
-                    if (!requestingPeer.sendMessage(arbitraryMetadataMessage)) {
+                    if (!requestingPeer.sendMessage(forwardArbitraryMetadataMessage)) {
                         requestingPeer.disconnect("failed to forward arbitrary metadata");
                     }
                 }
@@ -423,8 +425,7 @@ public class ArbitraryMetadataManager {
             // In relay mode - so ask our other peers if they have it
 
             long requestTime = getArbitraryMetadataMessage.getRequestTime();
-            int requestHops = getArbitraryMetadataMessage.getRequestHops();
-            getArbitraryMetadataMessage.setRequestHops(++requestHops);
+            int requestHops = getArbitraryMetadataMessage.getRequestHops() + 1;
             long totalRequestTime = now - requestTime;
 
             if (totalRequestTime < RELAY_REQUEST_MAX_DURATION) {
@@ -432,11 +433,14 @@ public class ArbitraryMetadataManager {
                 if (requestHops < RELAY_REQUEST_MAX_HOPS) {
                     // Relay request hasn't reached the maximum number of hops yet, so can be rebroadcast
 
+                    Message relayGetArbitraryMetadataMessage = new GetArbitraryMetadataMessage(signature, requestTime, requestHops);
+                    relayGetArbitraryMetadataMessage.setId(message.getId());
+
                     LOGGER.debug("Rebroadcasting metadata request from peer {} for signature {} to our other peers... totalRequestTime: {}, requestHops: {}", peer, Base58.encode(signature), totalRequestTime, requestHops);
                     Network.getInstance().broadcast(
-                            broadcastPeer -> broadcastPeer == peer ||
-                                    Objects.equals(broadcastPeer.getPeerData().getAddress().getHost(), peer.getPeerData().getAddress().getHost())
-                                    ? null : getArbitraryMetadataMessage);
+                            broadcastPeer ->
+                                    !broadcastPeer.isAtLeastVersion(RELAY_MIN_PEER_VERSION) ? null :
+                                    broadcastPeer == peer || Objects.equals(broadcastPeer.getPeerData().getAddress().getHost(), peer.getPeerData().getAddress().getHost()) ? null : relayGetArbitraryMetadataMessage);
 
                 }
                 else {

src/main/java/org/qortal/controller/repository/AtStatesPruner.java

@@ -19,6 +19,11 @@ public class AtStatesPruner implements Runnable {
 	public void run() {
 		Thread.currentThread().setName("AT States pruner");
 
+		if (Settings.getInstance().isLite()) {
+			// Nothing to prune in lite mode
+			return;
+		}
+
 		boolean archiveMode = false;
 		if (!Settings.getInstance().isTopOnly()) {
 			// Top-only mode isn't enabled, but we might want to prune for the purposes of archiving

src/main/java/org/qortal/controller/repository/AtStatesTrimmer.java

@@ -19,6 +19,11 @@ public class AtStatesTrimmer implements Runnable {
 	public void run() {
 		Thread.currentThread().setName("AT States trimmer");
 
+		if (Settings.getInstance().isLite()) {
+			// Nothing to trim in lite mode
+			return;
+		}
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			int trimStartHeight = repository.getATRepository().getAtTrimHeight();
 

src/main/java/org/qortal/controller/repository/BlockArchiver.java

@@ -16,12 +16,12 @@ public class BlockArchiver implements Runnable {
 
 	private static final Logger LOGGER = LogManager.getLogger(BlockArchiver.class);
 
-	private static final long INITIAL_SLEEP_PERIOD = 0L; // TODO: 5 * 60 * 1000L + 1234L; // ms
+	private static final long INITIAL_SLEEP_PERIOD = 5 * 60 * 1000L + 1234L; // ms
 
 	public void run() {
 		Thread.currentThread().setName("Block archiver");
 
-		if (!Settings.getInstance().isArchiveEnabled()) {
+		if (!Settings.getInstance().isArchiveEnabled() || Settings.getInstance().isLite()) {
 			return;
 		}
 

src/main/java/org/qortal/controller/repository/BlockPruner.java

@@ -19,6 +19,11 @@ public class BlockPruner implements Runnable {
 	public void run() {
 		Thread.currentThread().setName("Block pruner");
 
+		if (Settings.getInstance().isLite()) {
+			// Nothing to prune in lite mode
+			return;
+		}
+
 		boolean archiveMode = false;
 		if (!Settings.getInstance().isTopOnly()) {
 			// Top-only mode isn't enabled, but we might want to prune for the purposes of archiving

src/main/java/org/qortal/controller/repository/NamesDatabaseIntegrityCheck.java

@@ -107,7 +107,7 @@ public class NamesDatabaseIntegrityCheck {
                     BuyNameTransactionData buyNameTransactionData = (BuyNameTransactionData) currentTransaction;
                     Name nameObj = new Name(repository, buyNameTransactionData.getName());
                     if (nameObj != null && nameObj.getNameData() != null) {
-                        nameObj.buy(buyNameTransactionData);
+                        nameObj.buy(buyNameTransactionData, false);
                         modificationCount++;
                         LOGGER.trace("Processed BUY_NAME transaction for name {}", name);
                     }

src/main/java/org/qortal/controller/repository/OnlineAccountsSignaturesTrimmer.java

@@ -21,6 +21,11 @@ public class OnlineAccountsSignaturesTrimmer implements Runnable {
 	public void run() {
 		Thread.currentThread().setName("Online Accounts trimmer");
 
+		if (Settings.getInstance().isLite()) {
+			// Nothing to trim in lite mode
+			return;
+		}
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			// Don't even start trimming until initial rush has ended
 			Thread.sleep(INITIAL_SLEEP_PERIOD);

src/main/java/org/qortal/controller/tradebot/BitcoinACCTv3TradeBot.java

@@ -45,9 +45,9 @@ import static java.util.stream.Collectors.toMap;
  * 	<li>Trade-bot entries</li>
  * </ul>
  */
-public class DogecoinACCTv2TradeBot implements AcctTradeBot {
+public class BitcoinACCTv3TradeBot implements AcctTradeBot {
 
-	private static final Logger LOGGER = LogManager.getLogger(DogecoinACCTv2TradeBot.class);
+	private static final Logger LOGGER = LogManager.getLogger(BitcoinACCTv3TradeBot.class);
 
 	public enum State implements TradeBot.StateNameAndValueSupplier {
 		BOB_WAITING_FOR_AT_CONFIRM(10, false, false),
@@ -91,18 +91,18 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	/** Maximum time Bob waits for his AT creation transaction to be confirmed into a block. (milliseconds) */
 	private static final long MAX_AT_CONFIRMATION_PERIOD = 24 * 60 * 60 * 1000L; // ms
 
-	private static DogecoinACCTv2TradeBot instance;
+	private static BitcoinACCTv3TradeBot instance;
 
 	private final List<String> endStates = Arrays.asList(State.BOB_DONE, State.BOB_REFUNDED, State.ALICE_DONE, State.ALICE_REFUNDING_A, State.ALICE_REFUNDED).stream()
 			.map(State::name)
 			.collect(Collectors.toUnmodifiableList());
 
-	private DogecoinACCTv2TradeBot() {
+	private BitcoinACCTv3TradeBot() {
 	}
 
-	public static synchronized DogecoinACCTv2TradeBot getInstance() {
+	public static synchronized BitcoinACCTv3TradeBot getInstance() {
 		if (instance == null)
-			instance = new DogecoinACCTv2TradeBot();
+			instance = new BitcoinACCTv3TradeBot();
 
 		return instance;
 	}
@@ -113,7 +113,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	}
 
 	/**
-	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for DOGE.
+	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for BTC.
 	 * <p>
 	 * Generates:
 	 * <ul>
@@ -122,14 +122,14 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	 * Derives:
 	 * <ul>
 	 * 	<li>'native' (as in Qortal) public key, public key hash, address (starting with Q)</li>
-	 * 	<li>'foreign' (as in Dogecoin) public key, public key hash</li>
+	 * 	<li>'foreign' (as in Bitcoin) public key, public key hash</li>
 	 * </ul>
 	 * A Qortal AT is then constructed including the following as constants in the 'data segment':
 	 * <ul>
 	 * 	<li>'native'/Qortal 'trade' address - used as a MESSAGE contact</li>
-	 * 	<li>'foreign'/Dogecoin public key hash - used by Alice's P2SH scripts to allow redeem</li>
+	 * 	<li>'foreign'/Bitcoin public key hash - used by Alice's P2SH scripts to allow redeem</li>
 	 * 	<li>QORT amount on offer by Bob</li>
-	 * 	<li>DOGE amount expected in return by Bob (from Alice)</li>
+	 * 	<li>BTC amount expected in return by Bob (from Alice)</li>
 	 * 	<li>trading timeout, in case things go wrong and everyone needs to refund</li>
 	 * </ul>
 	 * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network.
@@ -151,17 +151,17 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
 		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
 
-		// Convert Dogecoin receiving address into public key hash (we only support P2PKH at this time)
-		Address dogecoinReceivingAddress;
+		// Convert Bitcoin receiving address into public key hash (we only support P2PKH at this time)
+		Address bitcoinReceivingAddress;
 		try {
-			dogecoinReceivingAddress = Address.fromString(Dogecoin.getInstance().getNetworkParameters(), tradeBotCreateRequest.receivingAddress);
+			bitcoinReceivingAddress = Address.fromString(Bitcoin.getInstance().getNetworkParameters(), tradeBotCreateRequest.receivingAddress);
 		} catch (AddressFormatException e) {
-			throw new DataException("Unsupported Dogecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
+			throw new DataException("Unsupported Bitcoin receiving address: " + tradeBotCreateRequest.receivingAddress);
 		}
-		if (dogecoinReceivingAddress.getOutputScriptType() != ScriptType.P2PKH)
-			throw new DataException("Unsupported Dogecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
+		if (bitcoinReceivingAddress.getOutputScriptType() != ScriptType.P2PKH)
+			throw new DataException("Unsupported Bitcoin receiving address: " + tradeBotCreateRequest.receivingAddress);
 
-		byte[] dogecoinReceivingAccountInfo = dogecoinReceivingAddress.getHash();
+		byte[] bitcoinReceivingAccountInfo = bitcoinReceivingAddress.getHash();
 
 		PublicKeyAccount creator = new PublicKeyAccount(repository, tradeBotCreateRequest.creatorPublicKey);
 
@@ -172,11 +172,11 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		byte[] signature = null;
 		BaseTransactionData baseTransactionData = new BaseTransactionData(timestamp, Group.NO_GROUP, reference, creator.getPublicKey(), fee, signature);
 
-		String name = "QORT/DOGE ACCT";
-		String description = "QORT/DOGE cross-chain trade";
+		String name = "QORT/BTC ACCT";
+		String description = "QORT/BTC cross-chain trade";
 		String aTType = "ACCT";
-		String tags = "ACCT QORT DOGE";
-		byte[] creationBytes = DogecoinACCTv2.buildQortalAT(tradeNativeAddress, tradeForeignPublicKeyHash, tradeBotCreateRequest.qortAmount,
+		String tags = "ACCT QORT BTC";
+		byte[] creationBytes = BitcoinACCTv3.buildQortalAT(tradeNativeAddress, tradeForeignPublicKeyHash, tradeBotCreateRequest.qortAmount,
 				tradeBotCreateRequest.foreignAmount, tradeBotCreateRequest.tradeTimeout);
 		long amount = tradeBotCreateRequest.fundingQortAmount;
 
@@ -189,14 +189,14 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		DeployAtTransaction.ensureATAddress(deployAtTransactionData);
 		String atAddress = deployAtTransactionData.getAtAddress();
 
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, DogecoinACCTv2.NAME,
+		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, BitcoinACCTv3.NAME,
 				State.BOB_WAITING_FOR_AT_CONFIRM.name(), State.BOB_WAITING_FOR_AT_CONFIRM.value,
 				creator.getAddress(), atAddress, timestamp, tradeBotCreateRequest.qortAmount,
 				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
 				null, null,
-				SupportedBlockchain.DOGECOIN.name(),
+				SupportedBlockchain.BITCOIN.name(),
 				tradeForeignPublicKey, tradeForeignPublicKeyHash,
-				tradeBotCreateRequest.foreignAmount, null, null, null, dogecoinReceivingAccountInfo);
+				tradeBotCreateRequest.foreignAmount, null, null, null, bitcoinReceivingAccountInfo);
 
 		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Built AT %s. Waiting for deployment", atAddress));
 
@@ -212,15 +212,15 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	}
 
 	/**
-	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching DOGE to an existing offer.
+	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching BTC to an existing offer.
 	 * <p>
 	 * Requires a chosen trade offer from Bob, passed by <tt>crossChainTradeData</tt>
-	 * and access to a Dogecoin wallet via <tt>xprv58</tt>.
+	 * and access to a Bitcoin wallet via <tt>xprv58</tt>.
 	 * <p>
 	 * The <tt>crossChainTradeData</tt> contains the current trade offer state
 	 * as extracted from the AT's data segment.
 	 * <p>
-	 * Access to a funded wallet is via a Dogecoin BIP32 hierarchical deterministic key,
+	 * Access to a funded wallet is via a Bitcoin BIP32 hierarchical deterministic key,
 	 * passed via <tt>xprv58</tt>.
 	 * <b>This key will be stored in your node's database</b>
 	 * to allow trade-bot to create/fund the necessary P2SH transactions!
@@ -230,15 +230,15 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	 * As an example, the xprv58 can be extract from a <i>legacy, password-less</i>
 	 * Electrum wallet by going to the console tab and entering:<br>
 	 * <tt>wallet.keystore.xprv</tt><br>
-	 * which should result in a base58 string starting with either 'xprv' (for Dogecoin main-net)
-	 * or 'tprv' for (Dogecoin test-net).
+	 * which should result in a base58 string starting with either 'xprv' (for Bitcoin main-net)
+	 * or 'tprv' for (Bitcoin test-net).
 	 * <p>
 	 * It is envisaged that the value in <tt>xprv58</tt> will actually come from a Qortal-UI-managed wallet.
 	 * <p>
 	 * If sufficient funds are available, <b>this method will actually fund the P2SH-A</b>
-	 * with the Dogecoin amount expected by 'Bob'.
+	 * with the Bitcoin amount expected by 'Bob'.
 	 * <p>
-	 * If the Dogecoin transaction is successfully broadcast to the network then
+	 * If the Bitcoin transaction is successfully broadcast to the network then
 	 * we also send a MESSAGE to Bob's trade-bot to let them know.
 	 * <p>
 	 * The trade-bot entry is saved to the repository and the cross-chain trading process commences.
@@ -246,7 +246,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	 * @param repository
 	 * @param crossChainTradeData chosen trade OFFER that Alice wants to match
 	 * @param xprv58 funded wallet xprv in base58
-	 * @return true if P2SH-A funding transaction successfully broadcast to Dogecoin network, false otherwise
+	 * @return true if P2SH-A funding transaction successfully broadcast to Bitcoin network, false otherwise
 	 * @throws DataException
 	 */
 	public ResponseResult startResponse(Repository repository, ATData atData, ACCT acct, CrossChainTradeData crossChainTradeData, String xprv58, String receivingAddress) throws DataException {
@@ -266,12 +266,12 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		long now = NTP.getTime();
 		int lockTimeA = crossChainTradeData.tradeTimeout * 60 + (int) (now / 1000L);
 
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, DogecoinACCTv2.NAME,
+		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, BitcoinACCTv3.NAME,
 				State.ALICE_WAITING_FOR_AT_LOCK.name(), State.ALICE_WAITING_FOR_AT_LOCK.value,
 				receivingAddress, crossChainTradeData.qortalAtAddress, now, crossChainTradeData.qortAmount,
 				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
 				secretA, hashOfSecretA,
-				SupportedBlockchain.DOGECOIN.name(),
+				SupportedBlockchain.BITCOIN.name(),
 				tradeForeignPublicKey, tradeForeignPublicKeyHash,
 				crossChainTradeData.expectedForeignAmount, xprv58, null, lockTimeA, receivingPublicKeyHash);
 
@@ -282,9 +282,9 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		// Check we have enough funds via xprv58 to fund P2SH to cover expectedForeignAmount
 		long p2shFee;
 		try {
-			p2shFee = Dogecoin.getInstance().getP2shFee(now);
+			p2shFee = Bitcoin.getInstance().getP2shFee(now);
 		} catch (ForeignBlockchainException e) {
-			LOGGER.debug("Couldn't estimate Dogecoin fees?");
+			LOGGER.debug("Couldn't estimate Bitcoin fees?");
 			return ResponseResult.NETWORK_ISSUE;
 		}
 
@@ -294,17 +294,17 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 
 		// P2SH-A to be funded
 		byte[] redeemScriptBytes = BitcoinyHTLC.buildScript(tradeForeignPublicKeyHash, lockTimeA, crossChainTradeData.creatorForeignPKH, hashOfSecretA);
-		String p2shAddress = Dogecoin.getInstance().deriveP2shAddress(redeemScriptBytes);
+		String p2shAddress = Bitcoin.getInstance().deriveP2shAddress(redeemScriptBytes);
 
 		// Build transaction for funding P2SH-A
-		Transaction p2shFundingTransaction = Dogecoin.getInstance().buildSpend(tradeBotData.getForeignKey(), p2shAddress, amountA);
+		Transaction p2shFundingTransaction = Bitcoin.getInstance().buildSpend(tradeBotData.getForeignKey(), p2shAddress, amountA);
 		if (p2shFundingTransaction == null) {
 			LOGGER.debug("Unable to build P2SH-A funding transaction - lack of funds?");
 			return ResponseResult.BALANCE_ISSUE;
 		}
 
 		try {
-			Dogecoin.getInstance().broadcastTransaction(p2shFundingTransaction);
+			Bitcoin.getInstance().broadcastTransaction(p2shFundingTransaction);
 		} catch (ForeignBlockchainException e) {
 			// We couldn't fund P2SH-A at this time
 			LOGGER.debug("Couldn't broadcast P2SH-A funding transaction?");
@@ -312,7 +312,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		}
 
 		// Attempt to send MESSAGE to Bob's Qortal trade address
-		byte[] messageData = DogecoinACCTv2.buildOfferMessage(tradeBotData.getTradeForeignPublicKeyHash(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
+		byte[] messageData = BitcoinACCTv3.buildOfferMessage(tradeBotData.getTradeForeignPublicKeyHash(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
 		String messageRecipient = crossChainTradeData.qortalCreatorTradeAddress;
 
 		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
@@ -354,6 +354,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			case BOB_DONE:
 			case ALICE_REFUNDED:
 			case BOB_REFUNDED:
+			case ALICE_REFUNDING_A:
 				return true;
 
 			default:
@@ -381,7 +382,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			}
 
 			if (tradeBotState.requiresTradeData) {
-				tradeData = DogecoinACCTv2.getInstance().populateTradeData(repository, atData);
+				tradeData = BitcoinACCTv3.getInstance().populateTradeData(repository, atData);
 				if (tradeData == null) {
 					LOGGER.warn(() -> String.format("Unable to fetch ACCT trade data for AT %s from repository", tradeBotData.getAtAddress()));
 					return;
@@ -462,7 +463,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	 * <p>
 	 * Details from Alice are used to derive P2SH-A address and this is checked for funding balance.
 	 * <p>
-	 * Assuming P2SH-A has at least expected Dogecoin balance,
+	 * Assuming P2SH-A has at least expected Bitcoin balance,
 	 * Bob's trade-bot constructs a zero-fee, PoW MESSAGE to send to Bob's AT with more trade details.
 	 * <p>
 	 * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice.
@@ -480,7 +481,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			return;
 		}
 
-		Dogecoin dogecoin = Dogecoin.getInstance();
+		Bitcoin bitcoin = Bitcoin.getInstance();
 
 		String address = tradeBotData.getTradeNativeAddress();
 		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, address, null, null, null);
@@ -489,27 +490,27 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			if (messageTransactionData.isText())
 				continue;
 
-			// We're expecting: HASH160(secret-A), Alice's Dogecoin pubkeyhash and lockTime-A
+			// We're expecting: HASH160(secret-A), Alice's Bitcoin pubkeyhash and lockTime-A
 			byte[] messageData = messageTransactionData.getData();
-			DogecoinACCTv2.OfferMessageData offerMessageData = DogecoinACCTv2.extractOfferMessageData(messageData);
+			BitcoinACCTv3.OfferMessageData offerMessageData = BitcoinACCTv3.extractOfferMessageData(messageData);
 			if (offerMessageData == null)
 				continue;
 
-			byte[] aliceForeignPublicKeyHash = offerMessageData.partnerDogecoinPKH;
+			byte[] aliceForeignPublicKeyHash = offerMessageData.partnerBitcoinPKH;
 			byte[] hashOfSecretA = offerMessageData.hashOfSecretA;
 			int lockTimeA = (int) offerMessageData.lockTimeA;
 			long messageTimestamp = messageTransactionData.getTimestamp();
-			int refundTimeout = DogecoinACCTv2.calcRefundTimeout(messageTimestamp, lockTimeA);
+			int refundTimeout = BitcoinACCTv3.calcRefundTimeout(messageTimestamp, lockTimeA);
 
 			// Determine P2SH-A address and confirm funded
 			byte[] redeemScriptA = BitcoinyHTLC.buildScript(aliceForeignPublicKeyHash, lockTimeA, tradeBotData.getTradeForeignPublicKeyHash(), hashOfSecretA);
-			String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
+			String p2shAddressA = bitcoin.deriveP2shAddress(redeemScriptA);
 
 			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
+			long p2shFee = Bitcoin.getInstance().getP2shFee(feeTimestamp);
 			final long minimumAmountA = tradeBotData.getForeignAmount() + p2shFee;
 
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -539,7 +540,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			String aliceNativeAddress = Crypto.toAddress(messageTransactionData.getCreatorPublicKey());
 
 			// Build outgoing message, padding each part to 32 bytes to make it easier for AT to consume
-			byte[] outgoingMessageData = DogecoinACCTv2.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKeyHash, hashOfSecretA, lockTimeA, refundTimeout);
+			byte[] outgoingMessageData = BitcoinACCTv3.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKeyHash, hashOfSecretA, lockTimeA, refundTimeout);
 			String messageRecipient = tradeBotData.getAtAddress();
 
 			boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, outgoingMessageData);
@@ -578,7 +579,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	 * <p>
 	 * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice.
 	 * <p>
-	 * In revealing a valid secret-A, Bob can then redeem the DOGE funds from P2SH-A.
+	 * In revealing a valid secret-A, Bob can then redeem the BTC funds from P2SH-A.
 	 * <p>
 	 * @throws ForeignBlockchainException
 	 */
@@ -587,19 +588,19 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		if (aliceUnexpectedState(repository, tradeBotData, atData, crossChainTradeData))
 			return;
 
-		Dogecoin dogecoin = Dogecoin.getInstance();
+		Bitcoin bitcoin = Bitcoin.getInstance();
 		int lockTimeA = tradeBotData.getLockTimeA();
 
 		// Refund P2SH-A if we've passed lockTime-A
 		if (NTP.getTime() >= lockTimeA * 1000L) {
 			byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-			String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
+			String p2shAddressA = bitcoin.deriveP2shAddress(redeemScriptA);
 
 			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
+			long p2shFee = Bitcoin.getInstance().getP2shFee(feeTimestamp);
 			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
 
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -645,7 +646,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		}
 
 		long recipientMessageTimestamp = messageTransactionsData.get(0).getTimestamp();
-		int refundTimeout = DogecoinACCTv2.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
+		int refundTimeout = BitcoinACCTv3.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
 
 		// Our calculated refundTimeout should match AT's refundTimeout
 		if (refundTimeout != crossChainTradeData.refundTimeout) {
@@ -659,7 +660,7 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		// Send 'redeem' MESSAGE to AT using both secret
 		byte[] secretA = tradeBotData.getSecret();
 		String qortalReceivingAddress = Base58.encode(tradeBotData.getReceivingAccountInfo()); // Actually contains whole address, not just PKH
-		byte[] messageData = DogecoinACCTv2.buildRedeemMessage(secretA, qortalReceivingAddress);
+		byte[] messageData = BitcoinACCTv3.buildRedeemMessage(secretA, qortalReceivingAddress);
 		String messageRecipient = tradeBotData.getAtAddress();
 
 		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
@@ -686,15 +687,15 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 	}
 
 	/**
-	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the DOGE funds from P2SH-A.
+	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the BTC funds from P2SH-A.
 	 * <p>
 	 * It's possible that Bob's AT has reached its trading timeout and automatically refunded QORT back to Bob. In which case,
 	 * trade-bot is done with this specific trade and finalizes in refunded state.
 	 * <p>
-	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the DOGE funds from P2SH-A
-	 * to Bob's 'foreign'/Dogecoin trade legacy-format address, as derived from trade private key.
+	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the BTC funds from P2SH-A
+	 * to Bob's 'foreign'/Bitcoin trade legacy-format address, as derived from trade private key.
 	 * <p>
-	 * (This could potentially be 'improved' to send DOGE to any address of Bob's choosing by changing the transaction output).
+	 * (This could potentially be 'improved' to send BTC to any address of Bob's choosing by changing the transaction output).
 	 * <p>
 	 * If trade-bot successfully broadcasts the transaction, then this specific trade is done.
 	 * @throws ForeignBlockchainException
@@ -708,14 +709,14 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 
 		// If AT is REFUNDED or CANCELLED then something has gone wrong
 		if (crossChainTradeData.mode == AcctMode.REFUNDED || crossChainTradeData.mode == AcctMode.CANCELLED) {
-			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the DOGE
+			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the BTC
 			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
 					() -> String.format("AT %s has auto-refunded - trade aborted", tradeBotData.getAtAddress()));
 
 			return;
 		}
 
-		byte[] secretA = DogecoinACCTv2.getInstance().findSecretA(repository, crossChainTradeData);
+		byte[] secretA = BitcoinACCTv3.getInstance().findSecretA(repository, crossChainTradeData);
 		if (secretA == null) {
 			LOGGER.debug(() -> String.format("Unable to find secret-A from redeem message to AT %s?", tradeBotData.getAtAddress()));
 			return;
@@ -723,18 +724,18 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 
 		// Use secret-A to redeem P2SH-A
 
-		Dogecoin dogecoin = Dogecoin.getInstance();
+		Bitcoin bitcoin = Bitcoin.getInstance();
 
 		byte[] receivingAccountInfo = tradeBotData.getReceivingAccountInfo();
 		int lockTimeA = crossChainTradeData.lockTimeA;
 		byte[] redeemScriptA = BitcoinyHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTimeA, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
-		String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
+		String p2shAddressA = bitcoin.deriveP2shAddress(redeemScriptA);
 
 		// Fee for redeem/refund is subtracted from P2SH-A balance.
 		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
+		long p2shFee = Bitcoin.getInstance().getP2shFee(feeTimestamp);
 		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 		switch (htlcStatusA) {
 			case UNFUNDED:
@@ -755,17 +756,17 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			case FUNDED: {
 				Coin redeemAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 				ECKey redeemKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = dogecoin.getUnspentOutputs(p2shAddressA);
+				List<TransactionOutput> fundingOutputs = bitcoin.getUnspentOutputs(p2shAddressA);
 
-				Transaction p2shRedeemTransaction = BitcoinyHTLC.buildRedeemTransaction(dogecoin.getNetworkParameters(), redeemAmount, redeemKey,
+				Transaction p2shRedeemTransaction = BitcoinyHTLC.buildRedeemTransaction(bitcoin.getNetworkParameters(), redeemAmount, redeemKey,
 						fundingOutputs, redeemScriptA, secretA, receivingAccountInfo);
 
-				dogecoin.broadcastTransaction(p2shRedeemTransaction);
+				bitcoin.broadcastTransaction(p2shRedeemTransaction);
 				break;
 			}
 		}
 
-		String receivingAddress = dogecoin.pkhToAddress(receivingAccountInfo);
+		String receivingAddress = bitcoin.pkhToAddress(receivingAccountInfo);
 
 		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
 				() -> String.format("P2SH-A %s redeemed. Funds should arrive at %s", tradeBotData.getAtAddress(), receivingAddress));
@@ -783,21 +784,21 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 		if (NTP.getTime() <= lockTimeA * 1000L)
 			return;
 
-		Dogecoin dogecoin = Dogecoin.getInstance();
+		Bitcoin bitcoin = Bitcoin.getInstance();
 
 		// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-		int medianBlockTime = dogecoin.getMedianBlockTime();
+		int medianBlockTime = bitcoin.getMedianBlockTime();
 		if (medianBlockTime <= lockTimeA)
 			return;
 
 		byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-		String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
+		String p2shAddressA = bitcoin.deriveP2shAddress(redeemScriptA);
 
 		// Fee for redeem/refund is subtracted from P2SH-A balance.
 		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
+		long p2shFee = Bitcoin.getInstance().getP2shFee(feeTimestamp);
 		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 		switch (htlcStatusA) {
 			case UNFUNDED:
@@ -819,16 +820,16 @@ public class DogecoinACCTv2TradeBot implements AcctTradeBot {
 			case FUNDED:{
 				Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 				ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = dogecoin.getUnspentOutputs(p2shAddressA);
+				List<TransactionOutput> fundingOutputs = bitcoin.getUnspentOutputs(p2shAddressA);
 
 				// Determine receive address for refund
-				String receiveAddress = dogecoin.getUnusedReceiveAddress(tradeBotData.getForeignKey());
-				Address receiving = Address.fromString(dogecoin.getNetworkParameters(), receiveAddress);
+				String receiveAddress = bitcoin.getUnusedReceiveAddress(tradeBotData.getForeignKey());
+				Address receiving = Address.fromString(bitcoin.getNetworkParameters(), receiveAddress);
 
-				Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(dogecoin.getNetworkParameters(), refundAmount, refundKey,
+				Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoin.getNetworkParameters(), refundAmount, refundKey,
 						fundingOutputs, redeemScriptA, lockTimeA, receiving.getHash());
 
-				dogecoin.broadcastTransaction(p2shRefundTransaction);
+				bitcoin.broadcastTransaction(p2shRefundTransaction);
 				break;
 			}
 		}

src/main/java/org/qortal/controller/tradebot/DigibyteACCTv3TradeBot.java

@@ -45,9 +45,9 @@ import static java.util.stream.Collectors.toMap;
  * 	<li>Trade-bot entries</li>
  * </ul>
  */
-public class LitecoinACCTv2TradeBot implements AcctTradeBot {
+public class DigibyteACCTv3TradeBot implements AcctTradeBot {
 
-	private static final Logger LOGGER = LogManager.getLogger(LitecoinACCTv2TradeBot.class);
+	private static final Logger LOGGER = LogManager.getLogger(DigibyteACCTv3TradeBot.class);
 
 	public enum State implements TradeBot.StateNameAndValueSupplier {
 		BOB_WAITING_FOR_AT_CONFIRM(10, false, false),
@@ -91,18 +91,18 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	/** Maximum time Bob waits for his AT creation transaction to be confirmed into a block. (milliseconds) */
 	private static final long MAX_AT_CONFIRMATION_PERIOD = 24 * 60 * 60 * 1000L; // ms
 
-	private static LitecoinACCTv2TradeBot instance;
+	private static DigibyteACCTv3TradeBot instance;
 
 	private final List<String> endStates = Arrays.asList(State.BOB_DONE, State.BOB_REFUNDED, State.ALICE_DONE, State.ALICE_REFUNDING_A, State.ALICE_REFUNDED).stream()
 			.map(State::name)
 			.collect(Collectors.toUnmodifiableList());
 
-	private LitecoinACCTv2TradeBot() {
+	private DigibyteACCTv3TradeBot() {
 	}
 
-	public static synchronized LitecoinACCTv2TradeBot getInstance() {
+	public static synchronized DigibyteACCTv3TradeBot getInstance() {
 		if (instance == null)
-			instance = new LitecoinACCTv2TradeBot();
+			instance = new DigibyteACCTv3TradeBot();
 
 		return instance;
 	}
@@ -113,7 +113,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	}
 
 	/**
-	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for LTC.
+	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for DGB.
 	 * <p>
 	 * Generates:
 	 * <ul>
@@ -122,14 +122,14 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	 * Derives:
 	 * <ul>
 	 * 	<li>'native' (as in Qortal) public key, public key hash, address (starting with Q)</li>
-	 * 	<li>'foreign' (as in Litecoin) public key, public key hash</li>
+	 * 	<li>'foreign' (as in Digibyte) public key, public key hash</li>
 	 * </ul>
 	 * A Qortal AT is then constructed including the following as constants in the 'data segment':
 	 * <ul>
 	 * 	<li>'native'/Qortal 'trade' address - used as a MESSAGE contact</li>
-	 * 	<li>'foreign'/Litecoin public key hash - used by Alice's P2SH scripts to allow redeem</li>
+	 * 	<li>'foreign'/Digibyte public key hash - used by Alice's P2SH scripts to allow redeem</li>
 	 * 	<li>QORT amount on offer by Bob</li>
-	 * 	<li>LTC amount expected in return by Bob (from Alice)</li>
+	 * 	<li>DGB amount expected in return by Bob (from Alice)</li>
 	 * 	<li>trading timeout, in case things go wrong and everyone needs to refund</li>
 	 * </ul>
 	 * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network.
@@ -151,17 +151,17 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
 		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
 
-		// Convert Litecoin receiving address into public key hash (we only support P2PKH at this time)
-		Address litecoinReceivingAddress;
+		// Convert Digibyte receiving address into public key hash (we only support P2PKH at this time)
+		Address digibyteReceivingAddress;
 		try {
-			litecoinReceivingAddress = Address.fromString(Litecoin.getInstance().getNetworkParameters(), tradeBotCreateRequest.receivingAddress);
+			digibyteReceivingAddress = Address.fromString(Digibyte.getInstance().getNetworkParameters(), tradeBotCreateRequest.receivingAddress);
 		} catch (AddressFormatException e) {
-			throw new DataException("Unsupported Litecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
+			throw new DataException("Unsupported Digibyte receiving address: " + tradeBotCreateRequest.receivingAddress);
 		}
-		if (litecoinReceivingAddress.getOutputScriptType() != ScriptType.P2PKH)
-			throw new DataException("Unsupported Litecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
+		if (digibyteReceivingAddress.getOutputScriptType() != ScriptType.P2PKH)
+			throw new DataException("Unsupported Digibyte receiving address: " + tradeBotCreateRequest.receivingAddress);
 
-		byte[] litecoinReceivingAccountInfo = litecoinReceivingAddress.getHash();
+		byte[] digibyteReceivingAccountInfo = digibyteReceivingAddress.getHash();
 
 		PublicKeyAccount creator = new PublicKeyAccount(repository, tradeBotCreateRequest.creatorPublicKey);
 
@@ -172,11 +172,11 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		byte[] signature = null;
 		BaseTransactionData baseTransactionData = new BaseTransactionData(timestamp, Group.NO_GROUP, reference, creator.getPublicKey(), fee, signature);
 
-		String name = "QORT/LTC ACCT";
-		String description = "QORT/LTC cross-chain trade";
+		String name = "QORT/DGB ACCT";
+		String description = "QORT/DGB cross-chain trade";
 		String aTType = "ACCT";
-		String tags = "ACCT QORT LTC";
-		byte[] creationBytes = LitecoinACCTv2.buildQortalAT(tradeNativeAddress, tradeForeignPublicKeyHash, tradeBotCreateRequest.qortAmount,
+		String tags = "ACCT QORT DGB";
+		byte[] creationBytes = DigibyteACCTv3.buildQortalAT(tradeNativeAddress, tradeForeignPublicKeyHash, tradeBotCreateRequest.qortAmount,
 				tradeBotCreateRequest.foreignAmount, tradeBotCreateRequest.tradeTimeout);
 		long amount = tradeBotCreateRequest.fundingQortAmount;
 
@@ -189,14 +189,14 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		DeployAtTransaction.ensureATAddress(deployAtTransactionData);
 		String atAddress = deployAtTransactionData.getAtAddress();
 
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, LitecoinACCTv2.NAME,
+		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, DigibyteACCTv3.NAME,
 				State.BOB_WAITING_FOR_AT_CONFIRM.name(), State.BOB_WAITING_FOR_AT_CONFIRM.value,
 				creator.getAddress(), atAddress, timestamp, tradeBotCreateRequest.qortAmount,
 				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
 				null, null,
-				SupportedBlockchain.LITECOIN.name(),
+				SupportedBlockchain.DIGIBYTE.name(),
 				tradeForeignPublicKey, tradeForeignPublicKeyHash,
-				tradeBotCreateRequest.foreignAmount, null, null, null, litecoinReceivingAccountInfo);
+				tradeBotCreateRequest.foreignAmount, null, null, null, digibyteReceivingAccountInfo);
 
 		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Built AT %s. Waiting for deployment", atAddress));
 
@@ -212,15 +212,15 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	}
 
 	/**
-	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching LTC to an existing offer.
+	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching DGB to an existing offer.
 	 * <p>
 	 * Requires a chosen trade offer from Bob, passed by <tt>crossChainTradeData</tt>
-	 * and access to a Litecoin wallet via <tt>xprv58</tt>.
+	 * and access to a Digibyte wallet via <tt>xprv58</tt>.
 	 * <p>
 	 * The <tt>crossChainTradeData</tt> contains the current trade offer state
 	 * as extracted from the AT's data segment.
 	 * <p>
-	 * Access to a funded wallet is via a Litecoin BIP32 hierarchical deterministic key,
+	 * Access to a funded wallet is via a Digibyte BIP32 hierarchical deterministic key,
 	 * passed via <tt>xprv58</tt>.
 	 * <b>This key will be stored in your node's database</b>
 	 * to allow trade-bot to create/fund the necessary P2SH transactions!
@@ -230,15 +230,15 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	 * As an example, the xprv58 can be extract from a <i>legacy, password-less</i>
 	 * Electrum wallet by going to the console tab and entering:<br>
 	 * <tt>wallet.keystore.xprv</tt><br>
-	 * which should result in a base58 string starting with either 'xprv' (for Litecoin main-net)
-	 * or 'tprv' for (Litecoin test-net).
+	 * which should result in a base58 string starting with either 'xprv' (for Digibyte main-net)
+	 * or 'tprv' for (Digibyte test-net).
 	 * <p>
 	 * It is envisaged that the value in <tt>xprv58</tt> will actually come from a Qortal-UI-managed wallet.
 	 * <p>
 	 * If sufficient funds are available, <b>this method will actually fund the P2SH-A</b>
-	 * with the Litecoin amount expected by 'Bob'.
+	 * with the Digibyte amount expected by 'Bob'.
 	 * <p>
-	 * If the Litecoin transaction is successfully broadcast to the network then
+	 * If the Digibyte transaction is successfully broadcast to the network then
 	 * we also send a MESSAGE to Bob's trade-bot to let them know.
 	 * <p>
 	 * The trade-bot entry is saved to the repository and the cross-chain trading process commences.
@@ -246,7 +246,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	 * @param repository
 	 * @param crossChainTradeData chosen trade OFFER that Alice wants to match
 	 * @param xprv58 funded wallet xprv in base58
-	 * @return true if P2SH-A funding transaction successfully broadcast to Litecoin network, false otherwise
+	 * @return true if P2SH-A funding transaction successfully broadcast to Digibyte network, false otherwise
 	 * @throws DataException
 	 */
 	public ResponseResult startResponse(Repository repository, ATData atData, ACCT acct, CrossChainTradeData crossChainTradeData, String xprv58, String receivingAddress) throws DataException {
@@ -266,12 +266,12 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		long now = NTP.getTime();
 		int lockTimeA = crossChainTradeData.tradeTimeout * 60 + (int) (now / 1000L);
 
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, LitecoinACCTv2.NAME,
+		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, DigibyteACCTv3.NAME,
 				State.ALICE_WAITING_FOR_AT_LOCK.name(), State.ALICE_WAITING_FOR_AT_LOCK.value,
 				receivingAddress, crossChainTradeData.qortalAtAddress, now, crossChainTradeData.qortAmount,
 				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
 				secretA, hashOfSecretA,
-				SupportedBlockchain.LITECOIN.name(),
+				SupportedBlockchain.DIGIBYTE.name(),
 				tradeForeignPublicKey, tradeForeignPublicKeyHash,
 				crossChainTradeData.expectedForeignAmount, xprv58, null, lockTimeA, receivingPublicKeyHash);
 
@@ -282,9 +282,9 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		// Check we have enough funds via xprv58 to fund P2SH to cover expectedForeignAmount
 		long p2shFee;
 		try {
-			p2shFee = Litecoin.getInstance().getP2shFee(now);
+			p2shFee = Digibyte.getInstance().getP2shFee(now);
 		} catch (ForeignBlockchainException e) {
-			LOGGER.debug("Couldn't estimate Litecoin fees?");
+			LOGGER.debug("Couldn't estimate Digibyte fees?");
 			return ResponseResult.NETWORK_ISSUE;
 		}
 
@@ -294,17 +294,17 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 
 		// P2SH-A to be funded
 		byte[] redeemScriptBytes = BitcoinyHTLC.buildScript(tradeForeignPublicKeyHash, lockTimeA, crossChainTradeData.creatorForeignPKH, hashOfSecretA);
-		String p2shAddress = Litecoin.getInstance().deriveP2shAddress(redeemScriptBytes);
+		String p2shAddress = Digibyte.getInstance().deriveP2shAddress(redeemScriptBytes);
 
 		// Build transaction for funding P2SH-A
-		Transaction p2shFundingTransaction = Litecoin.getInstance().buildSpend(tradeBotData.getForeignKey(), p2shAddress, amountA);
+		Transaction p2shFundingTransaction = Digibyte.getInstance().buildSpend(tradeBotData.getForeignKey(), p2shAddress, amountA);
 		if (p2shFundingTransaction == null) {
 			LOGGER.debug("Unable to build P2SH-A funding transaction - lack of funds?");
 			return ResponseResult.BALANCE_ISSUE;
 		}
 
 		try {
-			Litecoin.getInstance().broadcastTransaction(p2shFundingTransaction);
+			Digibyte.getInstance().broadcastTransaction(p2shFundingTransaction);
 		} catch (ForeignBlockchainException e) {
 			// We couldn't fund P2SH-A at this time
 			LOGGER.debug("Couldn't broadcast P2SH-A funding transaction?");
@@ -312,7 +312,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		}
 
 		// Attempt to send MESSAGE to Bob's Qortal trade address
-		byte[] messageData = LitecoinACCTv2.buildOfferMessage(tradeBotData.getTradeForeignPublicKeyHash(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
+		byte[] messageData = DigibyteACCTv3.buildOfferMessage(tradeBotData.getTradeForeignPublicKeyHash(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
 		String messageRecipient = crossChainTradeData.qortalCreatorTradeAddress;
 
 		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
@@ -382,7 +382,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 			}
 
 			if (tradeBotState.requiresTradeData) {
-				tradeData = LitecoinACCTv2.getInstance().populateTradeData(repository, atData);
+				tradeData = DigibyteACCTv3.getInstance().populateTradeData(repository, atData);
 				if (tradeData == null) {
 					LOGGER.warn(() -> String.format("Unable to fetch ACCT trade data for AT %s from repository", tradeBotData.getAtAddress()));
 					return;
@@ -463,7 +463,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	 * <p>
 	 * Details from Alice are used to derive P2SH-A address and this is checked for funding balance.
 	 * <p>
-	 * Assuming P2SH-A has at least expected Litecoin balance,
+	 * Assuming P2SH-A has at least expected Digibyte balance,
 	 * Bob's trade-bot constructs a zero-fee, PoW MESSAGE to send to Bob's AT with more trade details.
 	 * <p>
 	 * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice.
@@ -481,7 +481,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 			return;
 		}
 
-		Litecoin litecoin = Litecoin.getInstance();
+		Digibyte digibyte = Digibyte.getInstance();
 
 		String address = tradeBotData.getTradeNativeAddress();
 		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, address, null, null, null);
@@ -490,27 +490,27 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 			if (messageTransactionData.isText())
 				continue;
 
-			// We're expecting: HASH160(secret-A), Alice's Litecoin pubkeyhash and lockTime-A
+			// We're expecting: HASH160(secret-A), Alice's Digibyte pubkeyhash and lockTime-A
 			byte[] messageData = messageTransactionData.getData();
-			LitecoinACCTv2.OfferMessageData offerMessageData = LitecoinACCTv2.extractOfferMessageData(messageData);
+			DigibyteACCTv3.OfferMessageData offerMessageData = DigibyteACCTv3.extractOfferMessageData(messageData);
 			if (offerMessageData == null)
 				continue;
 
-			byte[] aliceForeignPublicKeyHash = offerMessageData.partnerLitecoinPKH;
+			byte[] aliceForeignPublicKeyHash = offerMessageData.partnerDigibytePKH;
 			byte[] hashOfSecretA = offerMessageData.hashOfSecretA;
 			int lockTimeA = (int) offerMessageData.lockTimeA;
 			long messageTimestamp = messageTransactionData.getTimestamp();
-			int refundTimeout = LitecoinACCTv2.calcRefundTimeout(messageTimestamp, lockTimeA);
+			int refundTimeout = DigibyteACCTv3.calcRefundTimeout(messageTimestamp, lockTimeA);
 
 			// Determine P2SH-A address and confirm funded
 			byte[] redeemScriptA = BitcoinyHTLC.buildScript(aliceForeignPublicKeyHash, lockTimeA, tradeBotData.getTradeForeignPublicKeyHash(), hashOfSecretA);
-			String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
+			String p2shAddressA = digibyte.deriveP2shAddress(redeemScriptA);
 
 			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
+			long p2shFee = Digibyte.getInstance().getP2shFee(feeTimestamp);
 			final long minimumAmountA = tradeBotData.getForeignAmount() + p2shFee;
 
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(digibyte.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -540,7 +540,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 			String aliceNativeAddress = Crypto.toAddress(messageTransactionData.getCreatorPublicKey());
 
 			// Build outgoing message, padding each part to 32 bytes to make it easier for AT to consume
-			byte[] outgoingMessageData = LitecoinACCTv2.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKeyHash, hashOfSecretA, lockTimeA, refundTimeout);
+			byte[] outgoingMessageData = DigibyteACCTv3.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKeyHash, hashOfSecretA, lockTimeA, refundTimeout);
 			String messageRecipient = tradeBotData.getAtAddress();
 
 			boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, outgoingMessageData);
@@ -579,7 +579,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	 * <p>
 	 * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice.
 	 * <p>
-	 * In revealing a valid secret-A, Bob can then redeem the LTC funds from P2SH-A.
+	 * In revealing a valid secret-A, Bob can then redeem the DGB funds from P2SH-A.
 	 * <p>
 	 * @throws ForeignBlockchainException
 	 */
@@ -588,19 +588,19 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		if (aliceUnexpectedState(repository, tradeBotData, atData, crossChainTradeData))
 			return;
 
-		Litecoin litecoin = Litecoin.getInstance();
+		Digibyte digibyte = Digibyte.getInstance();
 		int lockTimeA = tradeBotData.getLockTimeA();
 
 		// Refund P2SH-A if we've passed lockTime-A
 		if (NTP.getTime() >= lockTimeA * 1000L) {
 			byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-			String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
+			String p2shAddressA = digibyte.deriveP2shAddress(redeemScriptA);
 
 			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
+			long p2shFee = Digibyte.getInstance().getP2shFee(feeTimestamp);
 			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
 
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(digibyte.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -646,7 +646,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		}
 
 		long recipientMessageTimestamp = messageTransactionsData.get(0).getTimestamp();
-		int refundTimeout = LitecoinACCTv2.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
+		int refundTimeout = DigibyteACCTv3.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
 
 		// Our calculated refundTimeout should match AT's refundTimeout
 		if (refundTimeout != crossChainTradeData.refundTimeout) {
@@ -660,7 +660,7 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		// Send 'redeem' MESSAGE to AT using both secret
 		byte[] secretA = tradeBotData.getSecret();
 		String qortalReceivingAddress = Base58.encode(tradeBotData.getReceivingAccountInfo()); // Actually contains whole address, not just PKH
-		byte[] messageData = LitecoinACCTv2.buildRedeemMessage(secretA, qortalReceivingAddress);
+		byte[] messageData = DigibyteACCTv3.buildRedeemMessage(secretA, qortalReceivingAddress);
 		String messageRecipient = tradeBotData.getAtAddress();
 
 		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
@@ -687,15 +687,15 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 	}
 
 	/**
-	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the LTC funds from P2SH-A.
+	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the DGB funds from P2SH-A.
 	 * <p>
 	 * It's possible that Bob's AT has reached its trading timeout and automatically refunded QORT back to Bob. In which case,
 	 * trade-bot is done with this specific trade and finalizes in refunded state.
 	 * <p>
-	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the LTC funds from P2SH-A
-	 * to Bob's 'foreign'/Litecoin trade legacy-format address, as derived from trade private key.
+	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the DGB funds from P2SH-A
+	 * to Bob's 'foreign'/Digibyte trade legacy-format address, as derived from trade private key.
 	 * <p>
-	 * (This could potentially be 'improved' to send LTC to any address of Bob's choosing by changing the transaction output).
+	 * (This could potentially be 'improved' to send DGB to any address of Bob's choosing by changing the transaction output).
 	 * <p>
 	 * If trade-bot successfully broadcasts the transaction, then this specific trade is done.
 	 * @throws ForeignBlockchainException
@@ -709,14 +709,14 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 
 		// If AT is REFUNDED or CANCELLED then something has gone wrong
 		if (crossChainTradeData.mode == AcctMode.REFUNDED || crossChainTradeData.mode == AcctMode.CANCELLED) {
-			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the LTC
+			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the DGB
 			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
 					() -> String.format("AT %s has auto-refunded - trade aborted", tradeBotData.getAtAddress()));
 
 			return;
 		}
 
-		byte[] secretA = LitecoinACCTv2.getInstance().findSecretA(repository, crossChainTradeData);
+		byte[] secretA = DigibyteACCTv3.getInstance().findSecretA(repository, crossChainTradeData);
 		if (secretA == null) {
 			LOGGER.debug(() -> String.format("Unable to find secret-A from redeem message to AT %s?", tradeBotData.getAtAddress()));
 			return;
@@ -724,18 +724,18 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 
 		// Use secret-A to redeem P2SH-A
 
-		Litecoin litecoin = Litecoin.getInstance();
+		Digibyte digibyte = Digibyte.getInstance();
 
 		byte[] receivingAccountInfo = tradeBotData.getReceivingAccountInfo();
 		int lockTimeA = crossChainTradeData.lockTimeA;
 		byte[] redeemScriptA = BitcoinyHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTimeA, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
-		String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
+		String p2shAddressA = digibyte.deriveP2shAddress(redeemScriptA);
 
 		// Fee for redeem/refund is subtracted from P2SH-A balance.
 		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
+		long p2shFee = Digibyte.getInstance().getP2shFee(feeTimestamp);
 		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(digibyte.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 		switch (htlcStatusA) {
 			case UNFUNDED:
@@ -756,17 +756,17 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 			case FUNDED: {
 				Coin redeemAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 				ECKey redeemKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = litecoin.getUnspentOutputs(p2shAddressA);
+				List<TransactionOutput> fundingOutputs = digibyte.getUnspentOutputs(p2shAddressA);
 
-				Transaction p2shRedeemTransaction = BitcoinyHTLC.buildRedeemTransaction(litecoin.getNetworkParameters(), redeemAmount, redeemKey,
+				Transaction p2shRedeemTransaction = BitcoinyHTLC.buildRedeemTransaction(digibyte.getNetworkParameters(), redeemAmount, redeemKey,
 						fundingOutputs, redeemScriptA, secretA, receivingAccountInfo);
 
-				litecoin.broadcastTransaction(p2shRedeemTransaction);
+				digibyte.broadcastTransaction(p2shRedeemTransaction);
 				break;
 			}
 		}
 
-		String receivingAddress = litecoin.pkhToAddress(receivingAccountInfo);
+		String receivingAddress = digibyte.pkhToAddress(receivingAccountInfo);
 
 		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
 				() -> String.format("P2SH-A %s redeemed. Funds should arrive at %s", tradeBotData.getAtAddress(), receivingAddress));
@@ -784,21 +784,21 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 		if (NTP.getTime() <= lockTimeA * 1000L)
 			return;
 
-		Litecoin litecoin = Litecoin.getInstance();
+		Digibyte digibyte = Digibyte.getInstance();
 
 		// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-		int medianBlockTime = litecoin.getMedianBlockTime();
+		int medianBlockTime = digibyte.getMedianBlockTime();
 		if (medianBlockTime <= lockTimeA)
 			return;
 
 		byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-		String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
+		String p2shAddressA = digibyte.deriveP2shAddress(redeemScriptA);
 
 		// Fee for redeem/refund is subtracted from P2SH-A balance.
 		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
+		long p2shFee = Digibyte.getInstance().getP2shFee(feeTimestamp);
 		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(digibyte.getBlockchainProvider(), p2shAddressA, minimumAmountA);
 
 		switch (htlcStatusA) {
 			case UNFUNDED:
@@ -820,16 +820,16 @@ public class LitecoinACCTv2TradeBot implements AcctTradeBot {
 			case FUNDED:{
 				Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 				ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = litecoin.getUnspentOutputs(p2shAddressA);
+				List<TransactionOutput> fundingOutputs = digibyte.getUnspentOutputs(p2shAddressA);
 
 				// Determine receive address for refund
-				String receiveAddress = litecoin.getUnusedReceiveAddress(tradeBotData.getForeignKey());
-				Address receiving = Address.fromString(litecoin.getNetworkParameters(), receiveAddress);
+				String receiveAddress = digibyte.getUnusedReceiveAddress(tradeBotData.getForeignKey());
+				Address receiving = Address.fromString(digibyte.getNetworkParameters(), receiveAddress);
 
-				Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(litecoin.getNetworkParameters(), refundAmount, refundKey,
+				Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(digibyte.getNetworkParameters(), refundAmount, refundKey,
 						fundingOutputs, redeemScriptA, lockTimeA, receiving.getHash());
 
-				litecoin.broadcastTransaction(p2shRefundTransaction);
+				digibyte.broadcastTransaction(p2shRefundTransaction);
 				break;
 			}
 		}

src/main/java/org/qortal/controller/tradebot/PirateChainACCTv3TradeBot.java

@@ -0,0 +1,913 @@
+package org.qortal.controller.tradebot;
+
+import com.google.common.hash.HashCode;
+import com.rust.litewalletjni.LiteWalletJni;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.bitcoinj.core.*;
+import org.qortal.account.PrivateKeyAccount;
+import org.qortal.account.PublicKeyAccount;
+import org.qortal.api.model.crosschain.TradeBotCreateRequest;
+import org.qortal.asset.Asset;
+import org.qortal.crosschain.*;
+import org.qortal.crypto.Crypto;
+import org.qortal.data.at.ATData;
+import org.qortal.data.crosschain.CrossChainTradeData;
+import org.qortal.data.crosschain.TradeBotData;
+import org.qortal.data.transaction.BaseTransactionData;
+import org.qortal.data.transaction.DeployAtTransactionData;
+import org.qortal.data.transaction.MessageTransactionData;
+import org.qortal.group.Group;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.transaction.DeployAtTransaction;
+import org.qortal.transaction.MessageTransaction;
+import org.qortal.transaction.Transaction.ValidationResult;
+import org.qortal.transform.TransformationException;
+import org.qortal.transform.transaction.DeployAtTransactionTransformer;
+import org.qortal.utils.Base58;
+import org.qortal.utils.NTP;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import static java.util.Arrays.stream;
+import static java.util.stream.Collectors.toMap;
+
+/**
+ * Performing cross-chain trading steps on behalf of user.
+ * <p>
+ * We deal with three different independent state-spaces here:
+ * <ul>
+ * 	<li>Qortal blockchain</li>
+ * 	<li>Foreign blockchain</li>
+ * 	<li>Trade-bot entries</li>
+ * </ul>
+ */
+public class PirateChainACCTv3TradeBot implements AcctTradeBot {
+
+	private static final Logger LOGGER = LogManager.getLogger(PirateChainACCTv3TradeBot.class);
+
+	public enum State implements TradeBot.StateNameAndValueSupplier {
+		BOB_WAITING_FOR_AT_CONFIRM(10, false, false),
+		BOB_WAITING_FOR_MESSAGE(15, true, true),
+		BOB_WAITING_FOR_AT_REDEEM(25, true, true),
+		BOB_DONE(30, false, false),
+		BOB_REFUNDED(35, false, false),
+
+		ALICE_WAITING_FOR_AT_LOCK(85, true, true),
+		ALICE_DONE(95, false, false),
+		ALICE_REFUNDING_A(105, true, true),
+		ALICE_REFUNDED(110, false, false);
+
+		private static final Map<Integer, State> map = stream(State.values()).collect(toMap(state -> state.value, state -> state));
+
+		public final int value;
+		public final boolean requiresAtData;
+		public final boolean requiresTradeData;
+
+		State(int value, boolean requiresAtData, boolean requiresTradeData) {
+			this.value = value;
+			this.requiresAtData = requiresAtData;
+			this.requiresTradeData = requiresTradeData;
+		}
+
+		public static State valueOf(int value) {
+			return map.get(value);
+		}
+
+		@Override
+		public String getState() {
+			return this.name();
+		}
+
+		@Override
+		public int getStateValue() {
+			return this.value;
+		}
+	}
+
+	/** Maximum time Bob waits for his AT creation transaction to be confirmed into a block. (milliseconds) */
+	private static final long MAX_AT_CONFIRMATION_PERIOD = 24 * 60 * 60 * 1000L; // ms
+
+	private static PirateChainACCTv3TradeBot instance;
+
+	private final List<String> endStates = Arrays.asList(State.BOB_DONE, State.BOB_REFUNDED, State.ALICE_DONE, State.ALICE_REFUNDING_A, State.ALICE_REFUNDED).stream()
+			.map(State::name)
+			.collect(Collectors.toUnmodifiableList());
+
+	private PirateChainACCTv3TradeBot() {
+	}
+
+	public static synchronized PirateChainACCTv3TradeBot getInstance() {
+		if (instance == null)
+			instance = new PirateChainACCTv3TradeBot();
+
+		return instance;
+	}
+
+	@Override
+	public List<String> getEndStates() {
+		return this.endStates;
+	}
+
+	/**
+	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for ARRR.
+	 * <p>
+	 * Generates:
+	 * <ul>
+	 * 	<li>new 'trade' private key</li>
+	 * </ul>
+	 * Derives:
+	 * <ul>
+	 * 	<li>'native' (as in Qortal) public key, public key hash, address (starting with Q)</li>
+	 * 	<li>'foreign' (as in PirateChain) public key, public key hash</li>
+	 * </ul>
+	 * A Qortal AT is then constructed including the following as constants in the 'data segment':
+	 * <ul>
+	 * 	<li>'native'/Qortal 'trade' address - used as a MESSAGE contact</li>
+	 * 	<li>'foreign'/PirateChain public key hash - used by Alice's P2SH scripts to allow redeem</li>
+	 * 	<li>QORT amount on offer by Bob</li>
+	 * 	<li>ARRR amount expected in return by Bob (from Alice)</li>
+	 * 	<li>trading timeout, in case things go wrong and everyone needs to refund</li>
+	 * </ul>
+	 * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network.
+	 * <p>
+	 * Trade-bot will wait for Bob's AT to be deployed before taking next step.
+	 * <p>
+	 * @param repository
+	 * @param tradeBotCreateRequest
+	 * @return raw, unsigned DEPLOY_AT transaction
+	 * @throws DataException
+	 */
+	public byte[] createTrade(Repository repository, TradeBotCreateRequest tradeBotCreateRequest) throws DataException {
+		byte[] tradePrivateKey = TradeBot.generateTradePrivateKey();
+
+		byte[] tradeNativePublicKey = TradeBot.deriveTradeNativePublicKey(tradePrivateKey);
+		byte[] tradeNativePublicKeyHash = Crypto.hash160(tradeNativePublicKey);
+		String tradeNativeAddress = Crypto.toAddress(tradeNativePublicKey);
+
+		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
+		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
+
+		// ARRR wallet must be loaded before a trade can be created
+		// This is to stop trades from nodes on unsupported architectures (e.g. 32bit)
+		if (!LiteWalletJni.isLoaded()) {
+			throw new DataException("Pirate wallet not found. Check wallets screen for details.");
+		}
+
+		if (!PirateChain.getInstance().isValidAddress(tradeBotCreateRequest.receivingAddress)) {
+			throw new DataException("Unsupported Pirate Chain receiving address: " + tradeBotCreateRequest.receivingAddress);
+		}
+
+		Bech32.Bech32Data decodedReceivingAddress = Bech32.decode(tradeBotCreateRequest.receivingAddress);
+		byte[] pirateChainReceivingAccountInfo = decodedReceivingAddress.data;
+
+		PublicKeyAccount creator = new PublicKeyAccount(repository, tradeBotCreateRequest.creatorPublicKey);
+
+		// Deploy AT
+		long timestamp = NTP.getTime();
+		byte[] reference = creator.getLastReference();
+		long fee = 0L;
+		byte[] signature = null;
+		BaseTransactionData baseTransactionData = new BaseTransactionData(timestamp, Group.NO_GROUP, reference, creator.getPublicKey(), fee, signature);
+
+		String name = "QORT/ARRR ACCT";
+		String description = "QORT/ARRR cross-chain trade";
+		String aTType = "ACCT";
+		String tags = "ACCT QORT ARRR";
+		byte[] creationBytes = PirateChainACCTv3.buildQortalAT(tradeNativeAddress, tradeForeignPublicKey, tradeBotCreateRequest.qortAmount,
+				tradeBotCreateRequest.foreignAmount, tradeBotCreateRequest.tradeTimeout);
+		long amount = tradeBotCreateRequest.fundingQortAmount;
+
+		DeployAtTransactionData deployAtTransactionData = new DeployAtTransactionData(baseTransactionData, name, description, aTType, tags, creationBytes, amount, Asset.QORT);
+
+		DeployAtTransaction deployAtTransaction = new DeployAtTransaction(repository, deployAtTransactionData);
+		fee = deployAtTransaction.calcRecommendedFee();
+		deployAtTransactionData.setFee(fee);
+
+		DeployAtTransaction.ensureATAddress(deployAtTransactionData);
+		String atAddress = deployAtTransactionData.getAtAddress();
+
+		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, PirateChainACCTv3.NAME,
+				State.BOB_WAITING_FOR_AT_CONFIRM.name(), State.BOB_WAITING_FOR_AT_CONFIRM.value,
+				creator.getAddress(), atAddress, timestamp, tradeBotCreateRequest.qortAmount,
+				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
+				null, null,
+				SupportedBlockchain.PIRATECHAIN.name(),
+				tradeForeignPublicKey, tradeForeignPublicKeyHash,
+				tradeBotCreateRequest.foreignAmount, null, null, null, pirateChainReceivingAccountInfo);
+
+		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Built AT %s. Waiting for deployment", atAddress));
+
+		// Attempt to backup the trade bot data
+		TradeBot.backupTradeBotData(repository, null);
+
+		// Return to user for signing and broadcast as we don't have their Qortal private key
+		try {
+			return DeployAtTransactionTransformer.toBytes(deployAtTransactionData);
+		} catch (TransformationException e) {
+			throw new DataException("Failed to transform DEPLOY_AT transaction?", e);
+		}
+	}
+
+	/**
+	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching ARRR to an existing offer.
+	 * <p>
+	 * Requires a chosen trade offer from Bob, passed by <tt>crossChainTradeData</tt>
+	 * and access to a PirateChain wallet via <tt>xprv58</tt>.
+	 * <p>
+	 * The <tt>crossChainTradeData</tt> contains the current trade offer state
+	 * as extracted from the AT's data segment.
+	 * <p>
+	 * Access to a funded wallet is via a PirateChain BIP32 hierarchical deterministic key,
+	 * passed via <tt>xprv58</tt>.
+	 * <b>This key will be stored in your node's database</b>
+	 * to allow trade-bot to create/fund the necessary P2SH transactions!
+	 * However, due to the nature of BIP32 keys, it is possible to give the trade-bot
+	 * only a subset of wallet access (see BIP32 for more details).
+	 * <p>
+	 * As an example, the xprv58 can be extract from a <i>legacy, password-less</i>
+	 * Electrum wallet by going to the console tab and entering:<br>
+	 * <tt>wallet.keystore.xprv</tt><br>
+	 * which should result in a base58 string starting with either 'xprv' (for PirateChain main-net)
+	 * or 'tprv' for (PirateChain test-net).
+	 * <p>
+	 * It is envisaged that the value in <tt>xprv58</tt> will actually come from a Qortal-UI-managed wallet.
+	 * <p>
+	 * If sufficient funds are available, <b>this method will actually fund the P2SH-A</b>
+	 * with the PirateChain amount expected by 'Bob'.
+	 * <p>
+	 * If the PirateChain transaction is successfully broadcast to the network then
+	 * we also send a MESSAGE to Bob's trade-bot to let them know.
+	 * <p>
+	 * The trade-bot entry is saved to the repository and the cross-chain trading process commences.
+	 * <p>
+	 * @param repository
+	 * @param crossChainTradeData chosen trade OFFER that Alice wants to match
+	 * @param seed58 funded wallet xprv in base58
+	 * @return true if P2SH-A funding transaction successfully broadcast to PirateChain network, false otherwise
+	 * @throws DataException
+	 */
+	public ResponseResult startResponse(Repository repository, ATData atData, ACCT acct, CrossChainTradeData crossChainTradeData, String seed58, String receivingAddress) throws DataException {
+		byte[] tradePrivateKey = TradeBot.generateTradePrivateKey();
+		byte[] secretA = TradeBot.generateSecret();
+		byte[] hashOfSecretA = Crypto.hash160(secretA);
+
+		byte[] tradeNativePublicKey = TradeBot.deriveTradeNativePublicKey(tradePrivateKey);
+		byte[] tradeNativePublicKeyHash = Crypto.hash160(tradeNativePublicKey);
+		String tradeNativeAddress = Crypto.toAddress(tradeNativePublicKey);
+
+		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
+		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
+		byte[] receivingPublicKeyHash = Base58.decode(receivingAddress); // Actually the whole address, not just PKH
+
+		String tradePrivateKey58 = Base58.encode(tradePrivateKey);
+        String tradeForeignPublicKey58 = Base58.encode(tradeForeignPublicKey);
+		String secret58 = Base58.encode(secretA);
+
+		// We need to generate lockTime-A: add tradeTimeout to now
+		long now = NTP.getTime();
+		int lockTimeA = crossChainTradeData.tradeTimeout * 60 + (int) (now / 1000L);
+
+		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, PirateChainACCTv3.NAME,
+				State.ALICE_WAITING_FOR_AT_LOCK.name(), State.ALICE_WAITING_FOR_AT_LOCK.value,
+				receivingAddress, crossChainTradeData.qortalAtAddress, now, crossChainTradeData.qortAmount,
+				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
+				secretA, hashOfSecretA,
+				SupportedBlockchain.PIRATECHAIN.name(),
+				tradeForeignPublicKey, tradeForeignPublicKeyHash,
+				crossChainTradeData.expectedForeignAmount, seed58, null, lockTimeA, receivingPublicKeyHash);
+
+		// Attempt to backup the trade bot data
+		// Include tradeBotData as an additional parameter, since it's not in the repository yet
+		TradeBot.backupTradeBotData(repository, Arrays.asList(tradeBotData));
+
+		// Check we have enough funds via xprv58 to fund P2SH to cover expectedForeignAmount
+		long p2shFee;
+		try {
+			p2shFee = PirateChain.getInstance().getP2shFee(now);
+		} catch (ForeignBlockchainException e) {
+			LOGGER.debug("Couldn't estimate PirateChain fees?");
+			return ResponseResult.NETWORK_ISSUE;
+		}
+
+		// Fee for redeem/refund is subtracted from P2SH-A balance.
+		// Do not include fee for funding transaction as this is covered by buildSpend()
+		long amountA = crossChainTradeData.expectedForeignAmount + p2shFee /*redeeming/refunding P2SH-A*/;
+
+		// P2SH-A to be funded
+		byte[] redeemScriptBytes = PirateChainHTLC.buildScript(tradeForeignPublicKey, lockTimeA, crossChainTradeData.creatorForeignPKH, hashOfSecretA);
+		String p2shAddressT3 = PirateChain.getInstance().deriveP2shAddress(redeemScriptBytes); // Use t3 prefix when funding
+		byte[] redeemScriptWithPrefixBytes = PirateChainHTLC.buildScriptWithPrefix(tradeForeignPublicKey, lockTimeA, crossChainTradeData.creatorForeignPKH, hashOfSecretA);
+		String redeemScriptWithPrefix58 = Base58.encode(redeemScriptWithPrefixBytes);
+
+		// Send to P2SH address
+		try {
+			String txid = PirateChain.getInstance().fundP2SH(seed58, p2shAddressT3, amountA, redeemScriptWithPrefix58);
+			LOGGER.info("fundingTxidHex: {}", txid);
+
+		} catch (ForeignBlockchainException e) {
+			LOGGER.debug("Unable to build and send P2SH-A funding transaction - lack of funds?");
+			return ResponseResult.BALANCE_ISSUE;
+		}
+
+		// Attempt to send MESSAGE to Bob's Qortal trade address
+		byte[] messageData = PirateChainACCTv3.buildOfferMessage(tradeBotData.getTradeForeignPublicKey(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
+		String messageRecipient = crossChainTradeData.qortalCreatorTradeAddress;
+
+		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
+		if (!isMessageAlreadySent) {
+			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
+			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
+
+			messageTransaction.computeNonce();
+			messageTransaction.sign(sender);
+
+			// reset repository state to prevent deadlock
+			repository.discardChanges();
+			ValidationResult result = messageTransaction.importAsUnconfirmed();
+
+			if (result != ValidationResult.OK) {
+				LOGGER.warn(() -> String.format("Unable to send MESSAGE to Bob's trade-bot %s: %s", messageRecipient, result.name()));
+				return ResponseResult.NETWORK_ISSUE;
+			}
+		}
+
+		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Funding P2SH-A %s. Messaged Bob. Waiting for AT-lock", p2shAddressT3));
+
+		return ResponseResult.OK;
+	}
+
+	public static String hex(byte[] bytes) {
+		StringBuilder result = new StringBuilder();
+		for (byte aByte : bytes) {
+			result.append(String.format("%02x", aByte));
+			// upper case
+			// result.append(String.format("%02X", aByte));
+		}
+		return result.toString();
+	}
+
+	@Override
+	public boolean canDelete(Repository repository, TradeBotData tradeBotData) throws DataException {
+		State tradeBotState = State.valueOf(tradeBotData.getStateValue());
+		if (tradeBotState == null)
+			return true;
+
+		// If the AT doesn't exist then we might as well let the user tidy up
+		if (!repository.getATRepository().exists(tradeBotData.getAtAddress()))
+			return true;
+
+		switch (tradeBotState) {
+			case BOB_WAITING_FOR_AT_CONFIRM:
+			case ALICE_DONE:
+			case BOB_DONE:
+			case ALICE_REFUNDED:
+			case BOB_REFUNDED:
+			case ALICE_REFUNDING_A:
+				return true;
+
+			default:
+				return false;
+		}
+	}
+
+	@Override
+	public void progress(Repository repository, TradeBotData tradeBotData) throws DataException, ForeignBlockchainException {
+		State tradeBotState = State.valueOf(tradeBotData.getStateValue());
+		if (tradeBotState == null) {
+			LOGGER.info(() -> String.format("Trade-bot entry for AT %s has invalid state?", tradeBotData.getAtAddress()));
+			return;
+		}
+
+		ATData atData = null;
+		CrossChainTradeData tradeData = null;
+
+		if (tradeBotState.requiresAtData) {
+			// Attempt to fetch AT data
+			atData = repository.getATRepository().fromATAddress(tradeBotData.getAtAddress());
+			if (atData == null) {
+				LOGGER.debug(() -> String.format("Unable to fetch trade AT %s from repository", tradeBotData.getAtAddress()));
+				return;
+			}
+
+			if (tradeBotState.requiresTradeData) {
+				tradeData = PirateChainACCTv3.getInstance().populateTradeData(repository, atData);
+				if (tradeData == null) {
+					LOGGER.warn(() -> String.format("Unable to fetch ACCT trade data for AT %s from repository", tradeBotData.getAtAddress()));
+					return;
+				}
+			}
+		}
+
+		switch (tradeBotState) {
+			case BOB_WAITING_FOR_AT_CONFIRM:
+				handleBobWaitingForAtConfirm(repository, tradeBotData);
+				break;
+
+			case BOB_WAITING_FOR_MESSAGE:
+				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
+				handleBobWaitingForMessage(repository, tradeBotData, atData, tradeData);
+				break;
+
+			case ALICE_WAITING_FOR_AT_LOCK:
+				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
+				handleAliceWaitingForAtLock(repository, tradeBotData, atData, tradeData);
+				break;
+
+			case BOB_WAITING_FOR_AT_REDEEM:
+				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
+				handleBobWaitingForAtRedeem(repository, tradeBotData, atData, tradeData);
+				break;
+
+			case ALICE_DONE:
+			case BOB_DONE:
+				break;
+
+			case ALICE_REFUNDING_A:
+				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
+				handleAliceRefundingP2shA(repository, tradeBotData, atData, tradeData);
+				break;
+
+			case ALICE_REFUNDED:
+			case BOB_REFUNDED:
+				break;
+		}
+	}
+
+	/**
+	 * Trade-bot is waiting for Bob's AT to deploy.
+	 * <p>
+	 * If AT is deployed, then trade-bot's next step is to wait for MESSAGE from Alice.
+	 */
+	private void handleBobWaitingForAtConfirm(Repository repository, TradeBotData tradeBotData) throws DataException {
+		if (!repository.getATRepository().exists(tradeBotData.getAtAddress())) {
+			if (NTP.getTime() - tradeBotData.getTimestamp() <= MAX_AT_CONFIRMATION_PERIOD)
+				return;
+
+			// We've waited ages for AT to be confirmed into a block but something has gone awry.
+			// After this long we assume transaction loss so give up with trade-bot entry too.
+			tradeBotData.setState(State.BOB_REFUNDED.name());
+			tradeBotData.setStateValue(State.BOB_REFUNDED.value);
+			tradeBotData.setTimestamp(NTP.getTime());
+			// We delete trade-bot entry here instead of saving, hence not using updateTradeBotState()
+			repository.getCrossChainRepository().delete(tradeBotData.getTradePrivateKey());
+			repository.saveChanges();
+
+			LOGGER.info(() -> String.format("AT %s never confirmed. Giving up on trade", tradeBotData.getAtAddress()));
+			TradeBot.notifyStateChange(tradeBotData);
+			return;
+		}
+
+		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_WAITING_FOR_MESSAGE,
+				() -> String.format("AT %s confirmed ready. Waiting for trade message", tradeBotData.getAtAddress()));
+	}
+
+	/**
+	 * Trade-bot is waiting for MESSAGE from Alice's trade-bot, containing Alice's trade info.
+	 * <p>
+	 * It's possible Bob has cancelling his trade offer, receiving an automatic QORT refund,
+	 * in which case trade-bot is done with this specific trade and finalizes on refunded state.
+	 * <p>
+	 * Assuming trade is still on offer, trade-bot checks the contents of MESSAGE from Alice's trade-bot.
+	 * <p>
+	 * Details from Alice are used to derive P2SH-A address and this is checked for funding balance.
+	 * <p>
+	 * Assuming P2SH-A has at least expected PirateChain balance,
+	 * Bob's trade-bot constructs a zero-fee, PoW MESSAGE to send to Bob's AT with more trade details.
+	 * <p>
+	 * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice.
+	 * <p>
+	 * Trade-bot's next step is to wait for Alice to redeem the AT, which will allow Bob to
+	 * extract secret-A needed to redeem Alice's P2SH.
+	 * @throws ForeignBlockchainException
+	 */
+	private void handleBobWaitingForMessage(Repository repository, TradeBotData tradeBotData,
+			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
+		// If AT has finished then Bob likely cancelled his trade offer
+		if (atData.getIsFinished()) {
+			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
+					() -> String.format("AT %s cancelled - trading aborted", tradeBotData.getAtAddress()));
+			return;
+		}
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		String address = tradeBotData.getTradeNativeAddress();
+		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, address, null, null, null);
+
+		for (MessageTransactionData messageTransactionData : messageTransactionsData) {
+			if (messageTransactionData.isText())
+				continue;
+
+			// We're expecting: HASH160(secret-A), Alice's PirateChain pubkeyhash and lockTime-A
+			byte[] messageData = messageTransactionData.getData();
+			PirateChainACCTv3.OfferMessageData offerMessageData = PirateChainACCTv3.extractOfferMessageData(messageData);
+			if (offerMessageData == null)
+				continue;
+
+			byte[] aliceForeignPublicKey = offerMessageData.partnerPirateChainPublicKey;
+			byte[] hashOfSecretA = offerMessageData.hashOfSecretA;
+			int lockTimeA = (int) offerMessageData.lockTimeA;
+			long messageTimestamp = messageTransactionData.getTimestamp();
+			int refundTimeout = PirateChainACCTv3.calcRefundTimeout(messageTimestamp, lockTimeA);
+
+			// Determine P2SH-A address and confirm funded
+			byte[] redeemScriptA = PirateChainHTLC.buildScript(aliceForeignPublicKey, lockTimeA, tradeBotData.getTradeForeignPublicKey(), hashOfSecretA);
+			String p2shAddress = pirateChain.deriveP2shAddressBPrefix(redeemScriptA); // Use 'b' prefix when checking status
+
+			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
+			long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
+			final long minimumAmountA = tradeBotData.getForeignAmount() + p2shFee;
+
+			BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+
+			switch (htlcStatusA) {
+				case UNFUNDED:
+				case FUNDING_IN_PROGRESS:
+					// There might be another MESSAGE from someone else with an actually funded P2SH-A...
+					continue;
+
+				case REDEEM_IN_PROGRESS:
+				case REDEEMED:
+					// We've already redeemed this?
+					TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
+							() -> String.format("P2SH-A %s already spent? Assuming trade complete", p2shAddress));
+					return;
+
+				case REFUND_IN_PROGRESS:
+				case REFUNDED:
+					// This P2SH-A is burnt, but there might be another MESSAGE from someone else with an actually funded P2SH-A...
+					continue;
+
+				case FUNDED:
+					// Fall-through out of switch...
+					break;
+			}
+
+			// Good to go - send MESSAGE to AT
+
+			String aliceNativeAddress = Crypto.toAddress(messageTransactionData.getCreatorPublicKey());
+
+			// Build outgoing message, padding each part to 32 bytes to make it easier for AT to consume
+			byte[] outgoingMessageData = PirateChainACCTv3.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKey, hashOfSecretA, lockTimeA, refundTimeout);
+			String messageRecipient = tradeBotData.getAtAddress();
+
+			boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, outgoingMessageData);
+			if (!isMessageAlreadySent) {
+				PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
+				MessageTransaction outgoingMessageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, outgoingMessageData, false, false);
+
+				outgoingMessageTransaction.computeNonce();
+				outgoingMessageTransaction.sign(sender);
+
+				// reset repository state to prevent deadlock
+				repository.discardChanges();
+				ValidationResult result = outgoingMessageTransaction.importAsUnconfirmed();
+
+				if (result != ValidationResult.OK) {
+					LOGGER.warn(() -> String.format("Unable to send MESSAGE to AT %s: %s", messageRecipient, result.name()));
+					return;
+				}
+			}
+
+			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_WAITING_FOR_AT_REDEEM,
+					() -> String.format("Locked AT %s to %s. Waiting for AT redeem", tradeBotData.getAtAddress(), aliceNativeAddress));
+
+			return;
+		}
+	}
+
+	/**
+	 * Trade-bot is waiting for Bob's AT to switch to TRADE mode and lock trade to Alice only.
+	 * <p>
+	 * It's possible that Bob has cancelled his trade offer in the mean time, or that somehow
+	 * this process has taken so long that we've reached P2SH-A's locktime, or that someone else
+	 * has managed to trade with Bob. In any of these cases, trade-bot switches to begin the refunding process.
+	 * <p>
+	 * Assuming Bob's AT is locked to Alice, trade-bot checks AT's state data to make sure it is correct.
+	 * <p>
+	 * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice.
+	 * <p>
+	 * In revealing a valid secret-A, Bob can then redeem the ARRR funds from P2SH-A.
+	 * <p>
+	 * @throws ForeignBlockchainException
+	 */
+	private void handleAliceWaitingForAtLock(Repository repository, TradeBotData tradeBotData,
+			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
+		if (aliceUnexpectedState(repository, tradeBotData, atData, crossChainTradeData))
+			return;
+
+		PirateChain pirateChain = PirateChain.getInstance();
+		int lockTimeA = tradeBotData.getLockTimeA();
+
+		// Refund P2SH-A if we've passed lockTime-A
+		if (NTP.getTime() >= lockTimeA * 1000L) {
+			byte[] redeemScriptA = PirateChainHTLC.buildScript(tradeBotData.getTradeForeignPublicKey(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+			String p2shAddress = pirateChain.deriveP2shAddressBPrefix(redeemScriptA); // Use 'b' prefix when checking status
+
+			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
+			long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
+			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
+
+			BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+
+			switch (htlcStatusA) {
+				case UNFUNDED:
+				case FUNDING_IN_PROGRESS:
+				case FUNDED:
+					break;
+
+				case REDEEM_IN_PROGRESS:
+				case REDEEMED:
+					// Already redeemed?
+					TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
+							() -> String.format("P2SH-A %s already spent? Assuming trade completed", p2shAddress));
+					return;
+
+				case REFUND_IN_PROGRESS:
+				case REFUNDED:
+					TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDED,
+							() -> String.format("P2SH-A %s already refunded. Trade aborted", p2shAddress));
+					return;
+
+			}
+
+			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
+					() -> atData.getIsFinished()
+					? String.format("AT %s cancelled. Refunding P2SH-A %s - aborting trade", tradeBotData.getAtAddress(), p2shAddress)
+					: String.format("LockTime-A reached, refunding P2SH-A %s - aborting trade", p2shAddress));
+
+			return;
+		}
+
+		// We're waiting for AT to be in TRADE mode
+		if (crossChainTradeData.mode != AcctMode.TRADING)
+			return;
+
+		// AT is in TRADE mode and locked to us as checked by aliceUnexpectedState() above
+
+		// Find our MESSAGE to AT from previous state
+		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(tradeBotData.getTradeNativePublicKey(),
+				crossChainTradeData.qortalCreatorTradeAddress, null, null, null);
+		if (messageTransactionsData == null || messageTransactionsData.isEmpty()) {
+			LOGGER.warn(() -> String.format("Unable to find our message to trade creator %s?", crossChainTradeData.qortalCreatorTradeAddress));
+			return;
+		}
+
+		long recipientMessageTimestamp = messageTransactionsData.get(0).getTimestamp();
+		int refundTimeout = PirateChainACCTv3.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
+
+		// Our calculated refundTimeout should match AT's refundTimeout
+		if (refundTimeout != crossChainTradeData.refundTimeout) {
+			LOGGER.debug(() -> String.format("Trade AT refundTimeout '%d' doesn't match our refundTimeout '%d'", crossChainTradeData.refundTimeout, refundTimeout));
+			// We'll eventually refund
+			return;
+		}
+
+		// We're good to redeem AT
+
+		// Send 'redeem' MESSAGE to AT using both secret
+		byte[] secretA = tradeBotData.getSecret();
+		String qortalReceivingAddress = Base58.encode(tradeBotData.getReceivingAccountInfo()); // Actually contains whole address, not just PKH
+		byte[] messageData = PirateChainACCTv3.buildRedeemMessage(secretA, qortalReceivingAddress);
+		String messageRecipient = tradeBotData.getAtAddress();
+
+		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
+		if (!isMessageAlreadySent) {
+			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
+			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
+
+			messageTransaction.computeNonce();
+			messageTransaction.sign(sender);
+
+			// Reset repository state to prevent deadlock
+			repository.discardChanges();
+			ValidationResult result = messageTransaction.importAsUnconfirmed();
+
+			if (result != ValidationResult.OK) {
+				LOGGER.warn(() -> String.format("Unable to send MESSAGE to AT %s: %s", messageRecipient, result.name()));
+				return;
+			}
+		}
+
+		TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
+				() -> String.format("Redeeming AT %s. Funds should arrive at %s",
+						tradeBotData.getAtAddress(), qortalReceivingAddress));
+	}
+
+	/**
+	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the ARRR funds from P2SH-A.
+	 * <p>
+	 * It's possible that Bob's AT has reached its trading timeout and automatically refunded QORT back to Bob. In which case,
+	 * trade-bot is done with this specific trade and finalizes in refunded state.
+	 * <p>
+	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the ARRR funds from P2SH-A
+	 * to Bob's 'foreign'/PirateChain trade legacy-format address, as derived from trade private key.
+	 * <p>
+	 * (This could potentially be 'improved' to send ARRR to any address of Bob's choosing by changing the transaction output).
+	 * <p>
+	 * If trade-bot successfully broadcasts the transaction, then this specific trade is done.
+	 * @throws ForeignBlockchainException
+	 */
+	private void handleBobWaitingForAtRedeem(Repository repository, TradeBotData tradeBotData,
+			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
+		// AT should be 'finished' once Alice has redeemed QORT funds
+		if (!atData.getIsFinished())
+			// Not finished yet
+			return;
+
+		// If AT is REFUNDED or CANCELLED then something has gone wrong
+		if (crossChainTradeData.mode == AcctMode.REFUNDED || crossChainTradeData.mode == AcctMode.CANCELLED) {
+			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the ARRR
+			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
+					() -> String.format("AT %s has auto-refunded - trade aborted", tradeBotData.getAtAddress()));
+
+			return;
+		}
+
+		byte[] secretA = PirateChainACCTv3.getInstance().findSecretA(repository, crossChainTradeData);
+		if (secretA == null) {
+			LOGGER.debug(() -> String.format("Unable to find secret-A from redeem message to AT %s?", tradeBotData.getAtAddress()));
+			return;
+		}
+
+		// Use secret-A to redeem P2SH-A
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		byte[] receivingAccountInfo = tradeBotData.getReceivingAccountInfo();
+		int lockTimeA = crossChainTradeData.lockTimeA;
+		byte[] redeemScriptA = PirateChainHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTimeA, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
+		String p2shAddress = pirateChain.deriveP2shAddressBPrefix(redeemScriptA); // Use 'b' prefix when checking status
+		String p2shAddressT3 = pirateChain.deriveP2shAddress(redeemScriptA); // Use 't3' prefix when refunding
+
+		// Fee for redeem/refund is subtracted from P2SH-A balance.
+		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
+		long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
+		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
+		String receivingAddress = Bech32.encode("zs", receivingAccountInfo);
+
+		BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+
+		switch (htlcStatusA) {
+			case UNFUNDED:
+			case FUNDING_IN_PROGRESS:
+				// P2SH-A suddenly not funded? Our best bet at this point is to hope for AT auto-refund
+				return;
+
+			case REDEEM_IN_PROGRESS:
+			case REDEEMED:
+				// Double-check that we have redeemed P2SH-A...
+				break;
+
+			case REFUND_IN_PROGRESS:
+			case REFUNDED:
+				// Wait for AT to auto-refund
+				return;
+
+			case FUNDED: {
+				// Get funding txid
+				String fundingTxidHex = PirateChainHTLC.getUnspentFundingTxid(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+				if (fundingTxidHex == null) {
+					throw new ForeignBlockchainException("Missing funding txid when redeeming P2SH");
+				}
+				String fundingTxid58 = Base58.encode(HashCode.fromString(fundingTxidHex).asBytes());
+
+				// Redeem P2SH
+				Coin redeemAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
+				byte[] privateKey = tradeBotData.getTradePrivateKey();
+				String secret58 = Base58.encode(secretA);
+				String privateKey58 = Base58.encode(privateKey);
+				String redeemScript58 = Base58.encode(redeemScriptA);
+
+				String txid = PirateChain.getInstance().redeemP2sh(p2shAddressT3, receivingAddress, redeemAmount.value,
+						redeemScript58, fundingTxid58, secret58, privateKey58);
+				LOGGER.info("Redeem txid: {}", txid);
+				break;
+			}
+		}
+
+		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
+				() -> String.format("P2SH-A %s redeemed. Funds should arrive at %s", tradeBotData.getAtAddress(), receivingAddress));
+	}
+
+	/**
+	 * Trade-bot is attempting to refund P2SH-A.
+	 * @throws ForeignBlockchainException
+	 */
+	private void handleAliceRefundingP2shA(Repository repository, TradeBotData tradeBotData,
+			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
+		int lockTimeA = tradeBotData.getLockTimeA();
+
+		// We can't refund P2SH-A until lockTime-A has passed
+		if (NTP.getTime() <= lockTimeA * 1000L)
+			return;
+
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
+		int medianBlockTime = pirateChain.getMedianBlockTime();
+		if (medianBlockTime <= lockTimeA)
+			return;
+
+		byte[] redeemScriptA = PirateChainHTLC.buildScript(tradeBotData.getTradeForeignPublicKey(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+		String p2shAddress = pirateChain.deriveP2shAddressBPrefix(redeemScriptA); // Use 'b' prefix when checking status
+		String p2shAddressT3 = pirateChain.deriveP2shAddress(redeemScriptA); // Use 't3' prefix when refunding
+
+		// Fee for redeem/refund is subtracted from P2SH-A balance.
+		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
+		long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
+		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
+		BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+
+		switch (htlcStatusA) {
+			case UNFUNDED:
+			case FUNDING_IN_PROGRESS:
+				// Still waiting for P2SH-A to be funded...
+				return;
+
+			case REDEEM_IN_PROGRESS:
+			case REDEEMED:
+				// Too late!
+				TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
+						() -> String.format("P2SH-A %s already spent!", p2shAddress));
+				return;
+
+			case REFUND_IN_PROGRESS:
+			case REFUNDED:
+				break;
+
+			case FUNDED:{
+				// Get funding txid
+				String fundingTxidHex = PirateChainHTLC.getUnspentFundingTxid(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+				if (fundingTxidHex == null) {
+					throw new ForeignBlockchainException("Missing funding txid when refunding P2SH");
+				}
+				String fundingTxid58 = Base58.encode(HashCode.fromString(fundingTxidHex).asBytes());
+
+				Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
+				byte[] privateKey = tradeBotData.getTradePrivateKey();
+				String privateKey58 = Base58.encode(privateKey);
+				String redeemScript58 = Base58.encode(redeemScriptA);
+				String receivingAddress = pirateChain.getWalletAddress(tradeBotData.getForeignKey());
+
+				String txid = PirateChain.getInstance().refundP2sh(p2shAddressT3,
+						receivingAddress, refundAmount.value, redeemScript58, fundingTxid58, lockTimeA, privateKey58);
+				LOGGER.info("Refund txid: {}", txid);
+				break;
+			}
+		}
+
+		TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDED,
+				() -> String.format("LockTime-A reached. Refunded P2SH-A %s. Trade aborted", p2shAddress));
+	}
+
+	/**
+	 * Returns true if Alice finds AT unexpectedly cancelled, refunded, redeemed or locked to someone else.
+	 * <p>
+	 * Will automatically update trade-bot state to <tt>ALICE_REFUNDING_A</tt> or <tt>ALICE_DONE</tt> as necessary.
+	 * 
+	 * @throws DataException
+	 * @throws ForeignBlockchainException
+	 */
+	private boolean aliceUnexpectedState(Repository repository, TradeBotData tradeBotData,
+			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
+		// This is OK
+		if (!atData.getIsFinished() && crossChainTradeData.mode == AcctMode.OFFERING)
+			return false;
+
+		boolean isAtLockedToUs = tradeBotData.getTradeNativeAddress().equals(crossChainTradeData.qortalPartnerAddress);
+
+		if (!atData.getIsFinished() && crossChainTradeData.mode == AcctMode.TRADING)
+			if (isAtLockedToUs) {
+				// AT is trading with us - OK
+				return false;
+			} else {
+				TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
+						() -> String.format("AT %s trading with someone else: %s. Refunding & aborting trade", tradeBotData.getAtAddress(), crossChainTradeData.qortalPartnerAddress));
+
+				return true;
+			}
+
+		if (atData.getIsFinished() && crossChainTradeData.mode == AcctMode.REDEEMED && isAtLockedToUs) {
+			// We've redeemed already?
+			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
+					() -> String.format("AT %s already redeemed by us. Trade completed", tradeBotData.getAtAddress()));
+		} else {
+			// Any other state is not good, so start defensive refund
+			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
+					() -> String.format("AT %s cancelled/refunded/redeemed by someone else/invalid state. Refunding & aborting trade", tradeBotData.getAtAddress()));
+		}
+
+		return true;
+	}
+
+	private long calcFeeTimestamp(int lockTimeA, int tradeTimeout) {
+		return (lockTimeA - tradeTimeout * 60) * 1000L;
+	}
+
+}

src/main/java/org/qortal/controller/tradebot/TradeBot.java

@@ -94,13 +94,14 @@ public class TradeBot implements Listener {
 	private static final Map<Class<? extends ACCT>, Supplier<AcctTradeBot>> acctTradeBotSuppliers = new HashMap<>();
 	static {
 		acctTradeBotSuppliers.put(BitcoinACCTv1.class, BitcoinACCTv1TradeBot::getInstance);
+		acctTradeBotSuppliers.put(BitcoinACCTv3.class, BitcoinACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(LitecoinACCTv1.class, LitecoinACCTv1TradeBot::getInstance);
-		acctTradeBotSuppliers.put(LitecoinACCTv2.class, LitecoinACCTv2TradeBot::getInstance);
 		acctTradeBotSuppliers.put(LitecoinACCTv3.class, LitecoinACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(DogecoinACCTv1.class, DogecoinACCTv1TradeBot::getInstance);
-		acctTradeBotSuppliers.put(DogecoinACCTv2.class, DogecoinACCTv2TradeBot::getInstance);
 		acctTradeBotSuppliers.put(DogecoinACCTv3.class, DogecoinACCTv3TradeBot::getInstance);
+		acctTradeBotSuppliers.put(DigibyteACCTv3.class, DigibyteACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(RavencoinACCTv3.class, RavencoinACCTv3TradeBot::getInstance);
+		acctTradeBotSuppliers.put(PirateChainACCTv3.class, PirateChainACCTv3TradeBot::getInstance);
 	}
 
 	private static TradeBot instance;
@@ -240,8 +241,8 @@ public class TradeBot implements Listener {
 		if (!(event instanceof Synchronizer.NewChainTipEvent))
 			return;
 
-		// Don't process trade bots or broadcast presence timestamps if our chain is more than 30 minutes old
-		final Long minLatestBlockTimestamp = NTP.getTime() - (30 * 60 * 1000L);
+		// Don't process trade bots or broadcast presence timestamps if our chain is more than 60 minutes old
+		final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
 		if (!Controller.getInstance().isUpToDate(minLatestBlockTimestamp))
 			return;
 
@@ -290,14 +291,14 @@ public class TradeBot implements Listener {
 	}
 
 	public static byte[] deriveTradeNativePublicKey(byte[] privateKey) {
-		return PrivateKeyAccount.toPublicKey(privateKey);
+		return Crypto.toPublicKey(privateKey);
 	}
 
 	public static byte[] deriveTradeForeignPublicKey(byte[] privateKey) {
 		return ECKey.fromPrivate(privateKey).getPubKey();
 	}
 
-	/*package*/ static byte[] generateSecret() {
+	/*package*/ public static byte[] generateSecret() {
 		byte[] secret = new byte[32];
 		RANDOM.nextBytes(secret);
 		return secret;
@@ -467,9 +468,6 @@ public class TradeBot implements Listener {
 
 		List<TradePresenceData> safeTradePresences = List.copyOf(this.safeAllTradePresencesByPubkey.values());
 
-		if (safeTradePresences.isEmpty())
-			return;
-
 		LOGGER.debug("Broadcasting all {} known trade presences. Next broadcast timestamp: {}",
 				safeTradePresences.size(), nextTradePresenceBroadcastTimestamp
 		);
@@ -636,7 +634,7 @@ public class TradeBot implements Listener {
 		}
 
 		if (newCount > 0) {
-			LOGGER.debug("New trade presences: {}", newCount);
+			LOGGER.debug("New trade presences: {}, all trade presences: {}", newCount, allTradePresencesByPubkey.size());
 			rebuildSafeAllTradePresences();
 		}
 	}

src/main/java/org/qortal/crosschain/Bitcoin.java

@@ -7,6 +7,7 @@ import java.util.Map;
 
 import org.bitcoinj.core.Context;
 import org.bitcoinj.core.NetworkParameters;
+import org.bitcoinj.core.Transaction;
 import org.bitcoinj.params.MainNetParams;
 import org.bitcoinj.params.RegTestParams;
 import org.bitcoinj.params.TestNet3Params;
@@ -18,10 +19,12 @@ public class Bitcoin extends Bitcoiny {
 
 	public static final String CURRENCY_CODE = "BTC";
 
+	private static final long MINIMUM_ORDER_AMOUNT = 100000; // 0.001 BTC minimum order, due to high fees
+
 	// Temporary values until a dynamic fee system is written.
 	private static final long OLD_FEE_AMOUNT = 4_000L; // Not 5000 so that existing P2SH-B can output 1000, avoiding dust issue, leaving 4000 for fees.
 	private static final long NEW_FEE_TIMESTAMP = 1598280000000L; // milliseconds since epoch
-	private static final long NEW_FEE_AMOUNT = 10_000L;
+	private static final long NEW_FEE_AMOUNT = 6_000L;
 
 	private static final long NON_MAINNET_FEE = 1000L; // enough for TESTNET3 and should be OK for REGTEST
 
@@ -171,6 +174,8 @@ public class Bitcoin extends Bitcoiny {
 			Context bitcoinjContext = new Context(bitcoinNet.getParams());
 
 			instance = new Bitcoin(bitcoinNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;
@@ -182,6 +187,11 @@ public class Bitcoin extends Bitcoiny {
 		instance = null;
 	}
 
+	@Override
+	public long getMinimumOrderAmount() {
+		return MINIMUM_ORDER_AMOUNT;
+	}
+
 	// Actual useful methods for use by other classes
 
 	/**
@@ -195,4 +205,17 @@ public class Bitcoin extends Bitcoiny {
 		return this.bitcoinNet.getP2shFee(timestamp);
 	}
 
+	/**
+ 	* Returns bitcoinj transaction sending <tt>amount</tt> to <tt>recipient</tt> using 20 sat/byte fee.
+ 	*
+ 	* @param xprv58 BIP32 private key
+ 	* @param recipient P2PKH address
+ 	* @param amount unscaled amount
+ 	* @return transaction, or null if insufficient funds
+ 	*/
+	@Override
+	public Transaction buildSpend(String xprv58, String recipient, long amount) {
+		return buildSpend(xprv58, recipient, amount, 20L);
+	}
+
 }

src/main/java/org/qortal/crosschain/BitcoinACCTv3.java

@@ -29,7 +29,7 @@ import static org.ciyam.at.OpCode.calcOffset;
  * 
  * <p>
  * <ul>
- * <li>Bob generates Dogecoin & Qortal 'trade' keys
+ * <li>Bob generates Bitcoin & Qortal 'trade' keys
  * 		<ul>
  * 			<li>private key required to sign P2SH redeem tx</li>
  * 			<li>private key could be used to create 'secret' (e.g. double-SHA256)</li>
@@ -42,12 +42,12 @@ import static org.ciyam.at.OpCode.calcOffset;
  * </li>
  * <li>Alice finds Qortal AT and wants to trade
  * 		<ul>
- * 			<li>Alice generates Dogecoin & Qortal 'trade' keys</li>
- * 			<li>Alice funds Dogecoin P2SH-A</li>
+ * 			<li>Alice generates Bitcoin & Qortal 'trade' keys</li>
+ * 			<li>Alice funds Bitcoin P2SH-A</li>
  * 			<li>Alice sends 'offer' MESSAGE to Bob from her Qortal trade address, containing:
  * 				<ul>
  * 					<li>hash-of-secret-A</li>
- * 					<li>her 'trade' Dogecoin PKH</li>
+ * 					<li>her 'trade' Bitcoin PKH</li>
  * 				</ul>
  * 			</li>
  * 		</ul>
@@ -58,7 +58,7 @@ import static org.ciyam.at.OpCode.calcOffset;
  * 			<li>Sends 'trade' MESSAGE to Qortal AT from his trade address, containing:
  * 				<ul>
  * 					<li>Alice's trade Qortal address</li>
- * 					<li>Alice's trade Dogecoin PKH</li>
+ * 					<li>Alice's trade Bitcoin PKH</li>
  * 					<li>hash-of-secret-A</li>
  * 				</ul>
  * 			</li>
@@ -77,18 +77,18 @@ import static org.ciyam.at.OpCode.calcOffset;
  * </li>
  * <li>Bob checks AT, extracts secret-A
  * 		<ul>
- * 			<li>Bob redeems P2SH-A using his Dogecoin trade key and secret-A</li>
- * 			<li>P2SH-A DOGE funds end up at Dogecoin address determined by redeem transaction output(s)</li>
+ * 			<li>Bob redeems P2SH-A using his Bitcoin trade key and secret-A</li>
+ * 			<li>P2SH-A BTC funds end up at Bitcoin address determined by redeem transaction output(s)</li>
  * 		</ul>
  * </li>
  * </ul>
  */
-public class DogecoinACCTv2 implements ACCT {
+public class BitcoinACCTv3 implements ACCT {
 
-	private static final Logger LOGGER = LogManager.getLogger(DogecoinACCTv2.class);
+	private static final Logger LOGGER = LogManager.getLogger(BitcoinACCTv3.class);
 
-	public static final String NAME = DogecoinACCTv2.class.getSimpleName();
-	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("6fff38d6eeb06568a9c879c5628527730319844aa0de53f5f4ffab5506efe885").asBytes(); // SHA256 of AT code bytes
+	public static final String NAME = BitcoinACCTv3.class.getSimpleName();
+	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("676fb9350708dafa054eb0262d655039e393c1eb4918ec582f8d45524c9b4860").asBytes(); // SHA256 of AT code bytes
 
 	public static final int SECRET_LENGTH = 32;
 
@@ -98,27 +98,27 @@ public class DogecoinACCTv2 implements ACCT {
 	public static final int MODE_BYTE_OFFSET = MachineState.HEADER_LENGTH + (MODE_VALUE_OFFSET * MachineState.VALUE_SIZE);
 
 	public static class OfferMessageData {
-		public byte[] partnerDogecoinPKH;
+		public byte[] partnerBitcoinPKH;
 		public byte[] hashOfSecretA;
 		public long lockTimeA;
 	}
-	public static final int OFFER_MESSAGE_LENGTH = 20 /*partnerDogecoinPKH*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
+	public static final int OFFER_MESSAGE_LENGTH = 20 /*partnerBitcoinPKH*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
 	public static final int TRADE_MESSAGE_LENGTH = 32 /*partner's Qortal trade address (padded from 25 to 32)*/
-			+ 24 /*partner's Dogecoin PKH (padded from 20 to 24)*/
+			+ 24 /*partner's Bitcoin PKH (padded from 20 to 24)*/
 			+ 8 /*AT trade timeout (minutes)*/
 			+ 24 /*hash of secret-A (padded from 20 to 24)*/
 			+ 8 /*lockTimeA*/;
 	public static final int REDEEM_MESSAGE_LENGTH = 32 /*secret-A*/ + 32 /*partner's Qortal receiving address padded from 25 to 32*/;
 	public static final int CANCEL_MESSAGE_LENGTH = 32 /*AT creator's Qortal address*/;
 
-	private static DogecoinACCTv2 instance;
+	private static BitcoinACCTv3 instance;
 
-	private DogecoinACCTv2() {
+	private BitcoinACCTv3() {
 	}
 
-	public static synchronized DogecoinACCTv2 getInstance() {
+	public static synchronized BitcoinACCTv3 getInstance() {
 		if (instance == null)
-			instance = new DogecoinACCTv2();
+			instance = new BitcoinACCTv3();
 
 		return instance;
 	}
@@ -135,7 +135,7 @@ public class DogecoinACCTv2 implements ACCT {
 
 	@Override
 	public ForeignBlockchain getBlockchain() {
-		return Dogecoin.getInstance();
+		return Bitcoin.getInstance();
 	}
 
 	/**
@@ -145,14 +145,14 @@ public class DogecoinACCTv2 implements ACCT {
 	 * 32-byte secret to the AT, before the AT automatically refunds the AT's creator.
 	 * 
 	 * @param creatorTradeAddress AT creator's trade Qortal address
-	 * @param dogecoinPublicKeyHash 20-byte HASH160 of creator's trade Dogecoin public key
+	 * @param bitcoinPublicKeyHash 20-byte HASH160 of creator's trade Bitcoin public key
 	 * @param qortAmount how much QORT to pay trade partner if they send correct 32-byte secrets to AT
-	 * @param dogecoinAmount how much DOGE the AT creator is expecting to trade
+	 * @param bitcoinAmount how much BTC the AT creator is expecting to trade
 	 * @param tradeTimeout suggested timeout for entire trade
 	 */
-	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] dogecoinPublicKeyHash, long qortAmount, long dogecoinAmount, int tradeTimeout) {
-		if (dogecoinPublicKeyHash.length != 20)
-			throw new IllegalArgumentException("Dogecoin public key hash should be 20 bytes");
+	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] bitcoinPublicKeyHash, long qortAmount, long bitcoinAmount, int tradeTimeout) {
+		if (bitcoinPublicKeyHash.length != 20)
+			throw new IllegalArgumentException("Bitcoin public key hash should be 20 bytes");
 
 		// Labels for data segment addresses
 		int addrCounter = 0;
@@ -164,11 +164,11 @@ public class DogecoinACCTv2 implements ACCT {
 		final int addrCreatorTradeAddress3 = addrCounter++;
 		final int addrCreatorTradeAddress4 = addrCounter++;
 
-		final int addrDogecoinPublicKeyHash = addrCounter;
+		final int addrBitcoinPublicKeyHash = addrCounter;
 		addrCounter += 4;
 
 		final int addrQortAmount = addrCounter++;
-		final int addrDogecoinAmount = addrCounter++;
+		final int addrBitcoinAmount = addrCounter++;
 		final int addrTradeTimeout = addrCounter++;
 
 		final int addrMessageTxnType = addrCounter++;
@@ -179,8 +179,8 @@ public class DogecoinACCTv2 implements ACCT {
 		final int addrQortalPartnerAddressPointer = addrCounter++;
 		final int addrMessageSenderPointer = addrCounter++;
 
-		final int addrTradeMessagePartnerDogecoinPKHOffset = addrCounter++;
-		final int addrPartnerDogecoinPKHPointer = addrCounter++;
+		final int addrTradeMessagePartnerBitcoinPKHOffset = addrCounter++;
+		final int addrPartnerBitcoinPKHPointer = addrCounter++;
 		final int addrTradeMessageHashOfSecretAOffset = addrCounter++;
 		final int addrHashOfSecretAPointer = addrCounter++;
 
@@ -226,7 +226,7 @@ public class DogecoinACCTv2 implements ACCT {
 		final int addrHashOfSecretA = addrCounter;
 		addrCounter += 4;
 
-		final int addrPartnerDogecoinPKH = addrCounter;
+		final int addrPartnerBitcoinPKH = addrCounter;
 		addrCounter += 4;
 
 		final int addrPartnerReceivingAddress = addrCounter;
@@ -243,17 +243,17 @@ public class DogecoinACCTv2 implements ACCT {
 		byte[] creatorTradeAddressBytes = Base58.decode(creatorTradeAddress);
 		dataByteBuffer.put(Bytes.ensureCapacity(creatorTradeAddressBytes, 32, 0));
 
-		// Dogecoin public key hash
-		assert dataByteBuffer.position() == addrDogecoinPublicKeyHash * MachineState.VALUE_SIZE : "addrDogecoinPublicKeyHash incorrect";
-		dataByteBuffer.put(Bytes.ensureCapacity(dogecoinPublicKeyHash, 32, 0));
+		// Bitcoin public key hash
+		assert dataByteBuffer.position() == addrBitcoinPublicKeyHash * MachineState.VALUE_SIZE : "addrBitcoinPublicKeyHash incorrect";
+		dataByteBuffer.put(Bytes.ensureCapacity(bitcoinPublicKeyHash, 32, 0));
 
 		// Redeem Qort amount
 		assert dataByteBuffer.position() == addrQortAmount * MachineState.VALUE_SIZE : "addrQortAmount incorrect";
 		dataByteBuffer.putLong(qortAmount);
 
-		// Expected Dogecoin amount
-		assert dataByteBuffer.position() == addrDogecoinAmount * MachineState.VALUE_SIZE : "addrDogecoinAmount incorrect";
-		dataByteBuffer.putLong(dogecoinAmount);
+		// Expected Bitcoin amount
+		assert dataByteBuffer.position() == addrBitcoinAmount * MachineState.VALUE_SIZE : "addrBitcoinAmount incorrect";
+		dataByteBuffer.putLong(bitcoinAmount);
 
 		// Suggested trade timeout (minutes)
 		assert dataByteBuffer.position() == addrTradeTimeout * MachineState.VALUE_SIZE : "addrTradeTimeout incorrect";
@@ -283,13 +283,13 @@ public class DogecoinACCTv2 implements ACCT {
 		assert dataByteBuffer.position() == addrMessageSenderPointer * MachineState.VALUE_SIZE : "addrMessageSenderPointer incorrect";
 		dataByteBuffer.putLong(addrMessageSender1);
 
-		// Offset into 'trade' MESSAGE data payload for extracting partner's Dogecoin PKH
-		assert dataByteBuffer.position() == addrTradeMessagePartnerDogecoinPKHOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerDogecoinPKHOffset incorrect";
+		// Offset into 'trade' MESSAGE data payload for extracting partner's Bitcoin PKH
+		assert dataByteBuffer.position() == addrTradeMessagePartnerBitcoinPKHOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerBitcoinPKHOffset incorrect";
 		dataByteBuffer.putLong(32L);
 
-		// Index into data segment of partner's Dogecoin PKH, used by GET_B_IND
-		assert dataByteBuffer.position() == addrPartnerDogecoinPKHPointer * MachineState.VALUE_SIZE : "addrPartnerDogecoinPKHPointer incorrect";
-		dataByteBuffer.putLong(addrPartnerDogecoinPKH);
+		// Index into data segment of partner's Bitcoin PKH, used by GET_B_IND
+		assert dataByteBuffer.position() == addrPartnerBitcoinPKHPointer * MachineState.VALUE_SIZE : "addrPartnerBitcoinPKHPointer incorrect";
+		dataByteBuffer.putLong(addrPartnerBitcoinPKH);
 
 		// Offset into 'trade' MESSAGE data payload for extracting hash-of-secret-A
 		assert dataByteBuffer.position() == addrTradeMessageHashOfSecretAOffset * MachineState.VALUE_SIZE : "addrTradeMessageHashOfSecretAOffset incorrect";
@@ -338,9 +338,6 @@ public class DogecoinACCTv2 implements ACCT {
 			try {
 				/* Initialization */
 
-				/* NOP - to ensure DOGECOIN ACCT is unique */
-				codeByteBuffer.put(OpCode.NOP.compile());
-
 				// Use AT creation 'timestamp' as starting point for finding transactions sent to AT
 				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_CREATION_TIMESTAMP, addrLastTxnTimestamp));
 
@@ -429,10 +426,10 @@ public class DogecoinACCTv2 implements ACCT {
 				// Save B register into data segment starting at addrQortalPartnerAddress1 (as pointed to by addrQortalPartnerAddressPointer)
 				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrQortalPartnerAddressPointer));
 
-				// Extract trade partner's Dogecoin public key hash (PKH) from message into B
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerDogecoinPKHOffset));
-				// Store partner's Dogecoin PKH (we only really use values from B1-B3)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerDogecoinPKHPointer));
+				// Extract trade partner's Bitcoin public key hash (PKH) from message into B
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerBitcoinPKHOffset));
+				// Store partner's Bitcoin PKH (we only really use values from B1-B3)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerBitcoinPKHPointer));
 				// Extract AT trade timeout (minutes) (from B4)
 				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrRefundTimeout));
 
@@ -465,9 +462,6 @@ public class DogecoinACCTv2 implements ACCT {
 				/* Transaction processing loop */
 				labelRedeemTxnLoop = codeByteBuffer.position();
 
-				/* Sleep until message arrives */
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
-
 				// Find next transaction to this AT since the last one (if any)
 				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
 				// If no transaction found, A will be zero. If A is zero, set addrComparator to 1, otherwise 0.
@@ -541,12 +535,15 @@ public class DogecoinACCTv2 implements ACCT {
 				/* Refund balance back to AT creator */
 				labelRefund = codeByteBuffer.position();
 
+				/* NOP - to ensure BITCOIN ACCT is unique */
+				codeByteBuffer.put(OpCode.NOP.compile());
+
 				// Set refunded mode
 				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REFUNDED.value));
 				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
 				codeByteBuffer.put(OpCode.FIN_IMD.compile());
 			} catch (CompilationException e) {
-				throw new IllegalStateException("Unable to compile DOGE-QORT ACCT?", e);
+				throw new IllegalStateException("Unable to compile BTC-QORT ACCT?", e);
 			}
 		}
 
@@ -555,7 +552,7 @@ public class DogecoinACCTv2 implements ACCT {
 		byte[] codeBytes = new byte[codeByteBuffer.limit()];
 		codeByteBuffer.get(codeBytes);
 
-		assert Arrays.equals(Crypto.digest(codeBytes), DogecoinACCTv2.CODE_BYTES_HASH)
+		assert Arrays.equals(Crypto.digest(codeBytes), BitcoinACCTv3.CODE_BYTES_HASH)
 			: String.format("BTCACCT.CODE_BYTES_HASH mismatch: expected %s, actual %s", HashCode.fromBytes(CODE_BYTES_HASH), HashCode.fromBytes(Crypto.digest(codeBytes)));
 
 		final short ciyamAtVersion = 2;
@@ -593,7 +590,7 @@ public class DogecoinACCTv2 implements ACCT {
 
 		CrossChainTradeData tradeData = new CrossChainTradeData();
 
-		tradeData.foreignBlockchain = SupportedBlockchain.DOGECOIN.name();
+		tradeData.foreignBlockchain = SupportedBlockchain.BITCOIN.name();
 		tradeData.acctName = NAME;
 
 		tradeData.qortalAtAddress = atAddress;
@@ -614,7 +611,7 @@ public class DogecoinACCTv2 implements ACCT {
 		tradeData.qortalCreatorTradeAddress = Base58.encode(addressBytes);
 		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
 
-		// Creator's Dogecoin/foreign public key hash
+		// Creator's Bitcoin/foreign public key hash
 		tradeData.creatorForeignPKH = new byte[20];
 		dataByteBuffer.get(tradeData.creatorForeignPKH);
 		dataByteBuffer.position(dataByteBuffer.position() + 32 - tradeData.creatorForeignPKH.length); // skip to 32 bytes
@@ -625,7 +622,7 @@ public class DogecoinACCTv2 implements ACCT {
 		// Redeem payout
 		tradeData.qortAmount = dataByteBuffer.getLong();
 
-		// Expected DOGE amount
+		// Expected BTC amount
 		tradeData.expectedForeignAmount = dataByteBuffer.getLong();
 
 		// Trade timeout
@@ -649,10 +646,10 @@ public class DogecoinACCTv2 implements ACCT {
 		// Skip pointer to message sender
 		dataByteBuffer.position(dataByteBuffer.position() + 8);
 
-		// Skip 'trade' message data offset for partner's Dogecoin PKH
+		// Skip 'trade' message data offset for partner's Bitcoin PKH
 		dataByteBuffer.position(dataByteBuffer.position() + 8);
 
-		// Skip pointer to partner's Dogecoin PKH
+		// Skip pointer to partner's Bitcoin PKH
 		dataByteBuffer.position(dataByteBuffer.position() + 8);
 
 		// Skip 'trade' message data offset for hash-of-secret-A
@@ -718,10 +715,10 @@ public class DogecoinACCTv2 implements ACCT {
 		dataByteBuffer.get(hashOfSecretA);
 		dataByteBuffer.position(dataByteBuffer.position() + 32 - hashOfSecretA.length); // skip to 32 bytes
 
-		// Potential partner's Dogecoin PKH
-		byte[] partnerDogecoinPKH = new byte[20];
-		dataByteBuffer.get(partnerDogecoinPKH);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerDogecoinPKH.length); // skip to 32 bytes
+		// Potential partner's Bitcoin PKH
+		byte[] partnerBitcoinPKH = new byte[20];
+		dataByteBuffer.get(partnerBitcoinPKH);
+		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerBitcoinPKH.length); // skip to 32 bytes
 
 		// Partner's receiving address (if present)
 		byte[] partnerReceivingAddress = new byte[25];
@@ -740,7 +737,7 @@ public class DogecoinACCTv2 implements ACCT {
 			tradeData.tradeRefundHeight = new Timestamp(tradeRefundTimestamp).blockHeight;
 			tradeData.qortalPartnerAddress = qortalRecipient;
 			tradeData.hashOfSecretA = hashOfSecretA;
-			tradeData.partnerForeignPKH = partnerDogecoinPKH;
+			tradeData.partnerForeignPKH = partnerBitcoinPKH;
 			tradeData.lockTimeA = lockTimeA;
 
 			if (mode == AcctMode.REDEEMED)
@@ -766,7 +763,7 @@ public class DogecoinACCTv2 implements ACCT {
 			return null;
 
 		OfferMessageData offerMessageData = new OfferMessageData();
-		offerMessageData.partnerDogecoinPKH = Arrays.copyOfRange(messageData, 0, 20);
+		offerMessageData.partnerBitcoinPKH = Arrays.copyOfRange(messageData, 0, 20);
 		offerMessageData.hashOfSecretA = Arrays.copyOfRange(messageData, 20, 40);
 		offerMessageData.lockTimeA = BitTwiddling.longFromBEBytes(messageData, 40);
 

src/main/java/org/qortal/crosschain/Bitcoiny.java

@@ -29,6 +29,7 @@ import org.bitcoinj.wallet.SendRequest;
 import org.bitcoinj.wallet.Wallet;
 import org.qortal.api.model.SimpleForeignTransaction;
 import org.qortal.crypto.Crypto;
+import org.qortal.settings.Settings;
 import org.qortal.utils.Amounts;
 import org.qortal.utils.BitTwiddling;
 
@@ -42,7 +43,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 
 	public static final int HASH160_LENGTH = 20;
 
-	protected final BitcoinyBlockchainProvider blockchain;
+	protected final BitcoinyBlockchainProvider blockchainProvider;
 	protected final Context bitcoinjContext;
 	protected final String currencyCode;
 
@@ -61,18 +62,13 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	/** How many wallet keys to generate in each batch. */
 	private static final int WALLET_KEY_LOOKAHEAD_INCREMENT = 3;
 
-	/** How many wallet keys to generate when using bitcoinj as the data provider.
-	 * We must use a higher value here since we are unable to request multiple batches of keys.
-	 * Without this, the bitcoinj state can be missing transactions, causing errors such as "insufficient balance". */
-	private static final int WALLET_KEY_LOOKAHEAD_INCREMENT_BITCOINJ = 50;
-
 	/** Byte offset into raw block headers to block timestamp. */
 	private static final int TIMESTAMP_OFFSET = 4 + 32 + 32;
 
 	// Constructors and instance
 
-	protected Bitcoiny(BitcoinyBlockchainProvider blockchain, Context bitcoinjContext, String currencyCode) {
-		this.blockchain = blockchain;
+	protected Bitcoiny(BitcoinyBlockchainProvider blockchainProvider, Context bitcoinjContext, String currencyCode) {
+		this.blockchainProvider = blockchainProvider;
 		this.bitcoinjContext = bitcoinjContext;
 		this.currencyCode = currencyCode;
 
@@ -82,7 +78,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	// Getters & setters
 
 	public BitcoinyBlockchainProvider getBlockchainProvider() {
-		return this.blockchain;
+		return this.blockchainProvider;
 	}
 
 	public Context getBitcoinjContext() {
@@ -155,10 +151,10 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @throws ForeignBlockchainException if error occurs
 	 */
 	public int getMedianBlockTime() throws ForeignBlockchainException {
-		int height = this.blockchain.getCurrentHeight();
+		int height = this.blockchainProvider.getCurrentHeight();
 
 		// Grab latest 11 blocks
-		List<byte[]> blockHeaders = this.blockchain.getRawBlockHeaders(height - 11, 11);
+		List<byte[]> blockHeaders = this.blockchainProvider.getRawBlockHeaders(height - 11, 11);
 		if (blockHeaders.size() < 11)
 			throw new ForeignBlockchainException("Not enough blocks to determine median block time");
 
@@ -197,7 +193,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @throws ForeignBlockchainException if there was an error
 	 */
 	public long getConfirmedBalance(String base58Address) throws ForeignBlockchainException {
-		return this.blockchain.getConfirmedBalance(addressToScriptPubKey(base58Address));
+		return this.blockchainProvider.getConfirmedBalance(addressToScriptPubKey(base58Address));
 	}
 
 	/**
@@ -208,7 +204,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 */
 	// TODO: don't return bitcoinj-based objects like TransactionOutput, use BitcoinyTransaction.Output instead
 	public List<TransactionOutput> getUnspentOutputs(String base58Address) throws ForeignBlockchainException {
-		List<UnspentOutput> unspentOutputs = this.blockchain.getUnspentOutputs(addressToScriptPubKey(base58Address), false);
+		List<UnspentOutput> unspentOutputs = this.blockchainProvider.getUnspentOutputs(addressToScriptPubKey(base58Address), false);
 
 		List<TransactionOutput> unspentTransactionOutputs = new ArrayList<>();
 		for (UnspentOutput unspentOutput : unspentOutputs) {
@@ -228,7 +224,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 */
 	// TODO: don't return bitcoinj-based objects like TransactionOutput, use BitcoinyTransaction.Output instead
 	public List<TransactionOutput> getOutputs(byte[] txHash) throws ForeignBlockchainException {
-		byte[] rawTransactionBytes = this.blockchain.getRawTransaction(txHash);
+		byte[] rawTransactionBytes = this.blockchainProvider.getRawTransaction(txHash);
 
 		Context.propagate(bitcoinjContext);
 		Transaction transaction = new Transaction(this.params, rawTransactionBytes);
@@ -245,7 +241,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 		ForeignBlockchainException e2 = null;
 		while (retries <= 3) {
 			try {
-				return this.blockchain.getAddressTransactions(scriptPubKey, includeUnconfirmed);
+				return this.blockchainProvider.getAddressTransactions(scriptPubKey, includeUnconfirmed);
 			} catch (ForeignBlockchainException e) {
 				e2 = e;
 				retries++;
@@ -261,7 +257,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @throws ForeignBlockchainException if there was an error.
 	 */
 	public List<TransactionHash> getAddressTransactions(String base58Address, boolean includeUnconfirmed) throws ForeignBlockchainException {
-		return this.blockchain.getAddressTransactions(addressToScriptPubKey(base58Address), includeUnconfirmed);
+		return this.blockchainProvider.getAddressTransactions(addressToScriptPubKey(base58Address), includeUnconfirmed);
 	}
 
 	/**
@@ -270,11 +266,11 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @throws ForeignBlockchainException if there was an error
 	 */
 	public List<byte[]> getAddressTransactions(String base58Address) throws ForeignBlockchainException {
-		List<TransactionHash> transactionHashes = this.blockchain.getAddressTransactions(addressToScriptPubKey(base58Address), false);
+		List<TransactionHash> transactionHashes = this.blockchainProvider.getAddressTransactions(addressToScriptPubKey(base58Address), false);
 
 		List<byte[]> rawTransactions = new ArrayList<>();
 		for (TransactionHash transactionInfo : transactionHashes) {
-			byte[] rawTransaction = this.blockchain.getRawTransaction(HashCode.fromString(transactionInfo.txHash).asBytes());
+			byte[] rawTransaction = this.blockchainProvider.getRawTransaction(HashCode.fromString(transactionInfo.txHash).asBytes());
 			rawTransactions.add(rawTransaction);
 		}
 
@@ -292,7 +288,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 		ForeignBlockchainException e2 = null;
 		while (retries <= 3) {
 			try {
-				return this.blockchain.getTransaction(txHash);
+				return this.blockchainProvider.getTransaction(txHash);
 			} catch (ForeignBlockchainException e) {
 				e2 = e;
 				retries++;
@@ -307,7 +303,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @throws ForeignBlockchainException if error occurs
 	 */
 	public void broadcastTransaction(Transaction transaction) throws ForeignBlockchainException {
-		this.blockchain.broadcastTransaction(transaction.bitcoinSerialize());
+		this.blockchainProvider.broadcastTransaction(transaction.bitcoinSerialize());
 	}
 
 	/**
@@ -360,22 +356,25 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @param key58 BIP32/HD extended Bitcoin private/public key
 	 * @return unspent BTC balance, or null if unable to determine balance
 	 */
-	public Long getWalletBalance(String key58) {
-		Context.propagate(bitcoinjContext);
+	public Long getWalletBalance(String key58) throws ForeignBlockchainException {
+		// It's more accurate to calculate the balance from the transactions, rather than asking Bitcoinj
+		return this.getWalletBalanceFromTransactions(key58);
 
-		Wallet wallet = walletFromDeterministicKey58(key58);
-		wallet.setUTXOProvider(new WalletAwareUTXOProvider(this, wallet));
-
-		Coin balance = wallet.getBalance();
-		if (balance == null)
-			return null;
-
-		return balance.value;
+//		Context.propagate(bitcoinjContext);
+//
+//		Wallet wallet = walletFromDeterministicKey58(key58);
+//		wallet.setUTXOProvider(new WalletAwareUTXOProvider(this, wallet));
+//
+//		Coin balance = wallet.getBalance();
+//		if (balance == null)
+//			return null;
+//
+//		return balance.value;
 	}
 
 	public Long getWalletBalanceFromTransactions(String key58) throws ForeignBlockchainException {
 		long balance = 0;
-		Comparator<SimpleTransaction> oldestTimestampFirstComparator = Comparator.comparingInt(SimpleTransaction::getTimestamp);
+		Comparator<SimpleTransaction> oldestTimestampFirstComparator = Comparator.comparingLong(SimpleTransaction::getTimestamp);
 		List<SimpleTransaction> transactions = getWalletTransactions(key58).stream().sorted(oldestTimestampFirstComparator).collect(Collectors.toList());
 		for (SimpleTransaction transaction : transactions) {
 			balance += transaction.getTotalAmount();
@@ -409,9 +408,6 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 			Set<BitcoinyTransaction> walletTransactions = new HashSet<>();
 			Set<String> keySet = new HashSet<>();
 
-			// Set the number of consecutive empty batches required before giving up
-			final int numberOfAdditionalBatchesToSearch = 7;
-
 			int unusedCounter = 0;
 			int ki = 0;
 			do {
@@ -438,12 +434,12 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 
 				if (areAllKeysUnused) {
 					// No transactions
-					if (unusedCounter >= numberOfAdditionalBatchesToSearch) {
+					if (unusedCounter >= Settings.getInstance().getGapLimit()) {
 						// ... and we've hit our search limit
 						break;
 					}
 					// We haven't hit our search limit yet so increment the counter and keep looking
-					unusedCounter++;
+					unusedCounter += WALLET_KEY_LOOKAHEAD_INCREMENT;
 				} else {
 					// Some keys in this batch were used, so reset the counter
 					unusedCounter = 0;
@@ -455,7 +451,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 				// Process new keys
 			} while (true);
 
-			Comparator<SimpleTransaction> newestTimestampFirstComparator = Comparator.comparingInt(SimpleTransaction::getTimestamp).reversed();
+			Comparator<SimpleTransaction> newestTimestampFirstComparator = Comparator.comparingLong(SimpleTransaction::getTimestamp).reversed();
 
 			// Update cache and return
 			transactionsCacheTimestamp = NTP.getTime();
@@ -537,7 +533,8 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 			// All inputs and outputs relate to this wallet, so the balance should be unaffected
 			amount = 0;
 		}
-		return new SimpleTransaction(t.txHash, t.timestamp, amount, fee, inputs, outputs);
+		long timestampMillis = t.timestamp * 1000L;
+		return new SimpleTransaction(t.txHash, timestampMillis, amount, fee, inputs, outputs, null);
 	}
 
 	/**
@@ -573,7 +570,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 				Address address = Address.fromKey(this.params, dKey, ScriptType.P2PKH);
 				byte[] script = ScriptBuilder.createOutputScript(address).getProgram();
 
-				List<UnspentOutput> unspentOutputs = this.blockchain.getUnspentOutputs(script, false);
+				List<UnspentOutput> unspentOutputs = this.blockchainProvider.getUnspentOutputs(script, false);
 
 				/*
 				 * If there are no unspent outputs then either:
@@ -591,7 +588,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 					}
 
 					// Ask for transaction history - if it's empty then key has never been used
-					List<TransactionHash> historicTransactionHashes = this.blockchain.getAddressTransactions(script, false);
+					List<TransactionHash> historicTransactionHashes = this.blockchainProvider.getAddressTransactions(script, false);
 
 					if (!historicTransactionHashes.isEmpty()) {
 						// Fully spent key - case (a)
@@ -629,7 +626,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 			this.keyChain = this.wallet.getActiveKeyChain();
 
 			// Set up wallet's key chain
-			this.keyChain.setLookaheadSize(Bitcoiny.WALLET_KEY_LOOKAHEAD_INCREMENT_BITCOINJ);
+			this.keyChain.setLookaheadSize(Settings.getInstance().getBitcoinjLookaheadSize());
 			this.keyChain.maybeLookAhead();
 		}
 
@@ -650,7 +647,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 
 					List<UnspentOutput> unspentOutputs;
 					try {
-						unspentOutputs = this.bitcoiny.blockchain.getUnspentOutputs(script, false);
+						unspentOutputs = this.bitcoiny.blockchainProvider.getUnspentOutputs(script, false);
 					} catch (ForeignBlockchainException e) {
 						throw new UTXOProviderException(String.format("Unable to fetch unspent outputs for %s", address));
 					}
@@ -674,7 +671,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 						// Ask for transaction history - if it's empty then key has never been used
 						List<TransactionHash> historicTransactionHashes;
 						try {
-							historicTransactionHashes = this.bitcoiny.blockchain.getAddressTransactions(script, false);
+							historicTransactionHashes = this.bitcoiny.blockchainProvider.getAddressTransactions(script, false);
 						} catch (ForeignBlockchainException e) {
 							throw new UTXOProviderException(String.format("Unable to fetch transaction history for %s", address));
 						}
@@ -727,7 +724,7 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 		@Override
 		public int getChainHeadHeight() throws UTXOProviderException {
 			try {
-				return this.bitcoiny.blockchain.getCurrentHeight();
+				return this.bitcoiny.blockchainProvider.getCurrentHeight();
 			} catch (ForeignBlockchainException e) {
 				throw new UTXOProviderException("Unable to determine Bitcoiny chain height");
 			}

src/main/java/org/qortal/crosschain/BitcoinyBlockchainProvider.java

@@ -1,5 +1,7 @@
 package org.qortal.crosschain;
 
+import cash.z.wallet.sdk.rpc.CompactFormats.*;
+
 import java.util.List;
 
 public abstract class BitcoinyBlockchainProvider {
@@ -7,18 +9,32 @@ public abstract class BitcoinyBlockchainProvider {
 	public static final boolean INCLUDE_UNCONFIRMED = true;
 	public static final boolean EXCLUDE_UNCONFIRMED = false;
 
+	/** Sets the blockchain using this provider instance */
+	public abstract void setBlockchain(Bitcoiny blockchain);
+
 	/** Returns ID unique to bitcoiny network (e.g. "Litecoin-TEST3") */
 	public abstract String getNetId();
 
 	/** Returns current blockchain height. */
 	public abstract int getCurrentHeight() throws ForeignBlockchainException;
 
+	/** Returns a list of compact blocks, starting at <tt>startHeight</tt> (inclusive), up to <tt>count</tt> max.
+	 * Used for Pirate/Zcash only. If ever needed for other blockchains, the response format will need to be
+	 * made generic. */
+	public abstract List<CompactBlock> getCompactBlocks(int startHeight, int count) throws ForeignBlockchainException;
+
 	/** Returns a list of raw block headers, starting at <tt>startHeight</tt> (inclusive), up to <tt>count</tt> max. */
 	public abstract List<byte[]> getRawBlockHeaders(int startHeight, int count) throws ForeignBlockchainException;
 
+	/** Returns a list of block timestamps, starting at <tt>startHeight</tt> (inclusive), up to <tt>count</tt> max. */
+	public abstract List<Long> getBlockTimestamps(int startHeight, int count) throws ForeignBlockchainException;
+
 	/** Returns balance of address represented by <tt>scriptPubKey</tt>. */
 	public abstract long getConfirmedBalance(byte[] scriptPubKey) throws ForeignBlockchainException;
 
+	/** Returns balance of base58 encoded address. */
+	public abstract long getConfirmedAddressBalance(String base58Address) throws ForeignBlockchainException;
+
 	/** Returns raw, serialized, transaction bytes given <tt>txHash</tt>. */
 	public abstract byte[] getRawTransaction(String txHash) throws ForeignBlockchainException;
 
@@ -31,6 +47,12 @@ public abstract class BitcoinyBlockchainProvider {
 	/** Returns list of transaction hashes (and heights) for address represented by <tt>scriptPubKey</tt>, optionally including unconfirmed transactions. */
 	public abstract List<TransactionHash> getAddressTransactions(byte[] scriptPubKey, boolean includeUnconfirmed) throws ForeignBlockchainException;
 
+	/** Returns list of BitcoinyTransaction objects for <tt>address</tt>, optionally including unconfirmed transactions. */
+	public abstract List<BitcoinyTransaction> getAddressBitcoinyTransactions(String address, boolean includeUnconfirmed) throws ForeignBlockchainException;
+
+		/** Returns list of unspent transaction outputs for <tt>address</tt>, optionally including unconfirmed transactions. */
+	public abstract List<UnspentOutput> getUnspentOutputs(String address, boolean includeUnconfirmed) throws ForeignBlockchainException;
+
 	/** Returns list of unspent transaction outputs for address represented by <tt>scriptPubKey</tt>, optionally including unconfirmed transactions. */
 	public abstract List<UnspentOutput> getUnspentOutputs(byte[] scriptPubKey, boolean includeUnconfirmed) throws ForeignBlockchainException;
 

src/main/java/org/qortal/crosschain/BitcoinyTransaction.java

@@ -1,5 +1,6 @@
 package org.qortal.crosschain;
 
+import java.util.Comparator;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -10,8 +11,13 @@ import javax.xml.bind.annotation.XmlTransient;
 @XmlAccessorType(XmlAccessType.FIELD)
 public class BitcoinyTransaction {
 
+	public static final Comparator<BitcoinyTransaction> CONFIRMED_FIRST = (a, b) -> Boolean.compare(a.height != 0, b.height != 0);
+
 	public final String txHash;
 
+	@XmlTransient
+	public Integer height;
+
 	@XmlTransient
 	public final int size;
 
@@ -113,6 +119,10 @@ public class BitcoinyTransaction {
 		this.totalAmount = outputs.stream().map(output -> output.value).reduce(0L, Long::sum);
 	}
 
+	public int getHeight() {
+		return this.height;
+	}
+
 	public String toString() {
 		return String.format("txHash %s, size %d, locktime %d, timestamp %d\n"
 				+ "\tinputs: [%s]\n"

src/main/java/org/qortal/crosschain/Digibyte.java

@@ -0,0 +1,171 @@
+package org.qortal.crosschain;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.EnumMap;
+import java.util.Map;
+
+import org.bitcoinj.core.Coin;
+import org.bitcoinj.core.Context;
+import org.bitcoinj.core.NetworkParameters;
+import org.bitcoinj.params.RegTestParams;
+import org.bitcoinj.params.TestNet3Params;
+import org.libdohj.params.DigibyteMainNetParams;
+import org.qortal.crosschain.ElectrumX.Server;
+import org.qortal.crosschain.ElectrumX.Server.ConnectionType;
+import org.qortal.settings.Settings;
+
+public class Digibyte extends Bitcoiny {
+
+	public static final String CURRENCY_CODE = "DGB";
+
+	private static final Coin DEFAULT_FEE_PER_KB = Coin.valueOf(100000); // 0.001 DGB per 1000 bytes
+
+	private static final long MINIMUM_ORDER_AMOUNT = 1000000; // 0.01 DGB minimum order, to avoid dust errors
+
+	// Temporary values until a dynamic fee system is written.
+	private static final long MAINNET_FEE = 10000L;
+	private static final long NON_MAINNET_FEE = 10000L; // enough for TESTNET3 and should be OK for REGTEST
+
+	private static final Map<ConnectionType, Integer> DEFAULT_ELECTRUMX_PORTS = new EnumMap<>(ConnectionType.class);
+	static {
+		DEFAULT_ELECTRUMX_PORTS.put(ConnectionType.TCP, 50001);
+		DEFAULT_ELECTRUMX_PORTS.put(ConnectionType.SSL, 50002);
+	}
+
+	public enum DigibyteNet {
+		MAIN {
+			@Override
+			public NetworkParameters getParams() {
+				return DigibyteMainNetParams.get();
+			}
+
+			@Override
+			public Collection<Server> getServers() {
+				return Arrays.asList(
+						// Servers chosen on NO BASIS WHATSOEVER from various sources!
+						// Status verified at https://1209k.com/bitcoin-eye/ele.php?chain=dgb
+						new Server("electrum1.cipig.net", ConnectionType.SSL, 20059),
+						new Server("electrum2.cipig.net", ConnectionType.SSL, 20059),
+						new Server("electrum3.cipig.net", ConnectionType.SSL, 20059));
+			}
+
+			@Override
+			public String getGenesisHash() {
+				return "7497ea1b465eb39f1c8f507bc877078fe016d6fcb6dfad3a64c98dcc6e1e8496";
+			}
+
+			@Override
+			public long getP2shFee(Long timestamp) {
+				// TODO: This will need to be replaced with something better in the near future!
+				return MAINNET_FEE;
+			}
+		},
+		TEST3 {
+			@Override
+			public NetworkParameters getParams() {
+				return TestNet3Params.get();
+			}
+
+			@Override
+			public Collection<Server> getServers() {
+				return Arrays.asList(); // TODO: find testnet servers
+			}
+
+			@Override
+			public String getGenesisHash() {
+				return "308ea0711d5763be2995670dd9ca9872753561285a84da1d58be58acaa822252";
+			}
+
+			@Override
+			public long getP2shFee(Long timestamp) {
+				return NON_MAINNET_FEE;
+			}
+		},
+		REGTEST {
+			@Override
+			public NetworkParameters getParams() {
+				return RegTestParams.get();
+			}
+
+			@Override
+			public Collection<Server> getServers() {
+				return Arrays.asList(
+						new Server("localhost", ConnectionType.TCP, 50001),
+						new Server("localhost", ConnectionType.SSL, 50002));
+			}
+
+			@Override
+			public String getGenesisHash() {
+				// This is unique to each regtest instance
+				return null;
+			}
+
+			@Override
+			public long getP2shFee(Long timestamp) {
+				return NON_MAINNET_FEE;
+			}
+		};
+
+		public abstract NetworkParameters getParams();
+		public abstract Collection<Server> getServers();
+		public abstract String getGenesisHash();
+		public abstract long getP2shFee(Long timestamp) throws ForeignBlockchainException;
+	}
+
+	private static Digibyte instance;
+
+	private final DigibyteNet digibyteNet;
+
+	// Constructors and instance
+
+	private Digibyte(DigibyteNet digibyteNet, BitcoinyBlockchainProvider blockchain, Context bitcoinjContext, String currencyCode) {
+		super(blockchain, bitcoinjContext, currencyCode);
+		this.digibyteNet = digibyteNet;
+
+		LOGGER.info(() -> String.format("Starting Digibyte support using %s", this.digibyteNet.name()));
+	}
+
+	public static synchronized Digibyte getInstance() {
+		if (instance == null) {
+			DigibyteNet digibyteNet = Settings.getInstance().getDigibyteNet();
+
+			BitcoinyBlockchainProvider electrumX = new ElectrumX("Digibyte-" + digibyteNet.name(), digibyteNet.getGenesisHash(), digibyteNet.getServers(), DEFAULT_ELECTRUMX_PORTS);
+			Context bitcoinjContext = new Context(digibyteNet.getParams());
+
+			instance = new Digibyte(digibyteNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+		}
+
+		return instance;
+	}
+
+	// Getters & setters
+
+	public static synchronized void resetForTesting() {
+		instance = null;
+	}
+
+	// Actual useful methods for use by other classes
+
+	@Override
+	public Coin getFeePerKb() {
+		return DEFAULT_FEE_PER_KB;
+	}
+
+	@Override
+	public long getMinimumOrderAmount() {
+		return MINIMUM_ORDER_AMOUNT;
+	}
+
+	/**
+	 * Returns estimated DGB fee, in sats per 1000bytes, optionally for historic timestamp.
+	 * 
+	 * @param timestamp optional milliseconds since epoch, or null for 'now'
+	 * @return sats per 1000bytes, or throws ForeignBlockchainException if something went wrong
+	 */
+	@Override
+	public long getP2shFee(Long timestamp) throws ForeignBlockchainException {
+		return this.digibyteNet.getP2shFee(timestamp);
+	}
+
+}

src/main/java/org/qortal/crosschain/DigibyteACCTv3.java

@@ -2,6 +2,8 @@ package org.qortal.crosschain;
 
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Bytes;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.ciyam.at.*;
 import org.qortal.account.Account;
 import org.qortal.asset.Asset;
@@ -27,7 +29,7 @@ import static org.ciyam.at.OpCode.calcOffset;
  * 
  * <p>
  * <ul>
- * <li>Bob generates Litecoin & Qortal 'trade' keys
+ * <li>Bob generates Digibyte & Qortal 'trade' keys
  * 		<ul>
  * 			<li>private key required to sign P2SH redeem tx</li>
  * 			<li>private key could be used to create 'secret' (e.g. double-SHA256)</li>
@@ -40,12 +42,12 @@ import static org.ciyam.at.OpCode.calcOffset;
  * </li>
  * <li>Alice finds Qortal AT and wants to trade
  * 		<ul>
- * 			<li>Alice generates Litecoin & Qortal 'trade' keys</li>
- * 			<li>Alice funds Litecoin P2SH-A</li>
+ * 			<li>Alice generates Digibyte & Qortal 'trade' keys</li>
+ * 			<li>Alice funds Digibyte P2SH-A</li>
  * 			<li>Alice sends 'offer' MESSAGE to Bob from her Qortal trade address, containing:
  * 				<ul>
  * 					<li>hash-of-secret-A</li>
- * 					<li>her 'trade' Litecoin PKH</li>
+ * 					<li>her 'trade' Digibyte PKH</li>
  * 				</ul>
  * 			</li>
  * 		</ul>
@@ -56,7 +58,7 @@ import static org.ciyam.at.OpCode.calcOffset;
  * 			<li>Sends 'trade' MESSAGE to Qortal AT from his trade address, containing:
  * 				<ul>
  * 					<li>Alice's trade Qortal address</li>
- * 					<li>Alice's trade Litecoin PKH</li>
+ * 					<li>Alice's trade Digibyte PKH</li>
  * 					<li>hash-of-secret-A</li>
  * 				</ul>
  * 			</li>
@@ -75,16 +77,18 @@ import static org.ciyam.at.OpCode.calcOffset;
  * </li>
  * <li>Bob checks AT, extracts secret-A
  * 		<ul>
- * 			<li>Bob redeems P2SH-A using his Litecoin trade key and secret-A</li>
- * 			<li>P2SH-A LTC funds end up at Litecoin address determined by redeem transaction output(s)</li>
+ * 			<li>Bob redeems P2SH-A using his Digibyte trade key and secret-A</li>
+ * 			<li>P2SH-A DGB funds end up at Digibyte address determined by redeem transaction output(s)</li>
  * 		</ul>
  * </li>
  * </ul>
  */
-public class LitecoinACCTv2 implements ACCT {
+public class DigibyteACCTv3 implements ACCT {
 
-	public static final String NAME = LitecoinACCTv2.class.getSimpleName();
-	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("d5ea386a41441180c854ca8d7bbc620bfd53a97df2650a2b162b52324caf6e19").asBytes(); // SHA256 of AT code bytes
+	private static final Logger LOGGER = LogManager.getLogger(DigibyteACCTv3.class);
+
+	public static final String NAME = DigibyteACCTv3.class.getSimpleName();
+	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("e6a7dcd87296fae3ce7d80183bf7660c8e2cb4f8746c6a0421a17148f87a0e1d").asBytes(); // SHA256 of AT code bytes
 
 	public static final int SECRET_LENGTH = 32;
 
@@ -94,27 +98,27 @@ public class LitecoinACCTv2 implements ACCT {
 	public static final int MODE_BYTE_OFFSET = MachineState.HEADER_LENGTH + (MODE_VALUE_OFFSET * MachineState.VALUE_SIZE);
 
 	public static class OfferMessageData {
-		public byte[] partnerLitecoinPKH;
+		public byte[] partnerDigibytePKH;
 		public byte[] hashOfSecretA;
 		public long lockTimeA;
 	}
-	public static final int OFFER_MESSAGE_LENGTH = 20 /*partnerLitecoinPKH*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
+	public static final int OFFER_MESSAGE_LENGTH = 20 /*partnerDigibytePKH*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
 	public static final int TRADE_MESSAGE_LENGTH = 32 /*partner's Qortal trade address (padded from 25 to 32)*/
-			+ 24 /*partner's Litecoin PKH (padded from 20 to 24)*/
+			+ 24 /*partner's Digibyte PKH (padded from 20 to 24)*/
 			+ 8 /*AT trade timeout (minutes)*/
 			+ 24 /*hash of secret-A (padded from 20 to 24)*/
 			+ 8 /*lockTimeA*/;
 	public static final int REDEEM_MESSAGE_LENGTH = 32 /*secret-A*/ + 32 /*partner's Qortal receiving address padded from 25 to 32*/;
 	public static final int CANCEL_MESSAGE_LENGTH = 32 /*AT creator's Qortal address*/;
 
-	private static LitecoinACCTv2 instance;
+	private static DigibyteACCTv3 instance;
 
-	private LitecoinACCTv2() {
+	private DigibyteACCTv3() {
 	}
 
-	public static synchronized LitecoinACCTv2 getInstance() {
+	public static synchronized DigibyteACCTv3 getInstance() {
 		if (instance == null)
-			instance = new LitecoinACCTv2();
+			instance = new DigibyteACCTv3();
 
 		return instance;
 	}
@@ -131,7 +135,7 @@ public class LitecoinACCTv2 implements ACCT {
 
 	@Override
 	public ForeignBlockchain getBlockchain() {
-		return Litecoin.getInstance();
+		return Digibyte.getInstance();
 	}
 
 	/**
@@ -141,14 +145,14 @@ public class LitecoinACCTv2 implements ACCT {
 	 * 32-byte secret to the AT, before the AT automatically refunds the AT's creator.
 	 * 
 	 * @param creatorTradeAddress AT creator's trade Qortal address
-	 * @param litecoinPublicKeyHash 20-byte HASH160 of creator's trade Litecoin public key
+	 * @param digibytePublicKeyHash 20-byte HASH160 of creator's trade Digibyte public key
 	 * @param qortAmount how much QORT to pay trade partner if they send correct 32-byte secrets to AT
-	 * @param litecoinAmount how much LTC the AT creator is expecting to trade
+	 * @param digibyteAmount how much DGB the AT creator is expecting to trade
 	 * @param tradeTimeout suggested timeout for entire trade
 	 */
-	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] litecoinPublicKeyHash, long qortAmount, long litecoinAmount, int tradeTimeout) {
-		if (litecoinPublicKeyHash.length != 20)
-			throw new IllegalArgumentException("Litecoin public key hash should be 20 bytes");
+	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] digibytePublicKeyHash, long qortAmount, long digibyteAmount, int tradeTimeout) {
+		if (digibytePublicKeyHash.length != 20)
+			throw new IllegalArgumentException("Digibyte public key hash should be 20 bytes");
 
 		// Labels for data segment addresses
 		int addrCounter = 0;
@@ -160,11 +164,11 @@ public class LitecoinACCTv2 implements ACCT {
 		final int addrCreatorTradeAddress3 = addrCounter++;
 		final int addrCreatorTradeAddress4 = addrCounter++;
 
-		final int addrLitecoinPublicKeyHash = addrCounter;
+		final int addrDigibytePublicKeyHash = addrCounter;
 		addrCounter += 4;
 
 		final int addrQortAmount = addrCounter++;
-		final int addrLitecoinAmount = addrCounter++;
+		final int addrDigibyteAmount = addrCounter++;
 		final int addrTradeTimeout = addrCounter++;
 
 		final int addrMessageTxnType = addrCounter++;
@@ -175,8 +179,8 @@ public class LitecoinACCTv2 implements ACCT {
 		final int addrQortalPartnerAddressPointer = addrCounter++;
 		final int addrMessageSenderPointer = addrCounter++;
 
-		final int addrTradeMessagePartnerLitecoinPKHOffset = addrCounter++;
-		final int addrPartnerLitecoinPKHPointer = addrCounter++;
+		final int addrTradeMessagePartnerDigibytePKHOffset = addrCounter++;
+		final int addrPartnerDigibytePKHPointer = addrCounter++;
 		final int addrTradeMessageHashOfSecretAOffset = addrCounter++;
 		final int addrHashOfSecretAPointer = addrCounter++;
 
@@ -222,7 +226,7 @@ public class LitecoinACCTv2 implements ACCT {
 		final int addrHashOfSecretA = addrCounter;
 		addrCounter += 4;
 
-		final int addrPartnerLitecoinPKH = addrCounter;
+		final int addrPartnerDigibytePKH = addrCounter;
 		addrCounter += 4;
 
 		final int addrPartnerReceivingAddress = addrCounter;
@@ -239,17 +243,17 @@ public class LitecoinACCTv2 implements ACCT {
 		byte[] creatorTradeAddressBytes = Base58.decode(creatorTradeAddress);
 		dataByteBuffer.put(Bytes.ensureCapacity(creatorTradeAddressBytes, 32, 0));
 
-		// Litecoin public key hash
-		assert dataByteBuffer.position() == addrLitecoinPublicKeyHash * MachineState.VALUE_SIZE : "addrLitecoinPublicKeyHash incorrect";
-		dataByteBuffer.put(Bytes.ensureCapacity(litecoinPublicKeyHash, 32, 0));
+		// Digibyte public key hash
+		assert dataByteBuffer.position() == addrDigibytePublicKeyHash * MachineState.VALUE_SIZE : "addrDigibytePublicKeyHash incorrect";
+		dataByteBuffer.put(Bytes.ensureCapacity(digibytePublicKeyHash, 32, 0));
 
 		// Redeem Qort amount
 		assert dataByteBuffer.position() == addrQortAmount * MachineState.VALUE_SIZE : "addrQortAmount incorrect";
 		dataByteBuffer.putLong(qortAmount);
 
-		// Expected Litecoin amount
-		assert dataByteBuffer.position() == addrLitecoinAmount * MachineState.VALUE_SIZE : "addrLitecoinAmount incorrect";
-		dataByteBuffer.putLong(litecoinAmount);
+		// Expected Digibyte amount
+		assert dataByteBuffer.position() == addrDigibyteAmount * MachineState.VALUE_SIZE : "addrDigibyteAmount incorrect";
+		dataByteBuffer.putLong(digibyteAmount);
 
 		// Suggested trade timeout (minutes)
 		assert dataByteBuffer.position() == addrTradeTimeout * MachineState.VALUE_SIZE : "addrTradeTimeout incorrect";
@@ -279,13 +283,13 @@ public class LitecoinACCTv2 implements ACCT {
 		assert dataByteBuffer.position() == addrMessageSenderPointer * MachineState.VALUE_SIZE : "addrMessageSenderPointer incorrect";
 		dataByteBuffer.putLong(addrMessageSender1);
 
-		// Offset into 'trade' MESSAGE data payload for extracting partner's Litecoin PKH
-		assert dataByteBuffer.position() == addrTradeMessagePartnerLitecoinPKHOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerLitecoinPKHOffset incorrect";
+		// Offset into 'trade' MESSAGE data payload for extracting partner's Digibyte PKH
+		assert dataByteBuffer.position() == addrTradeMessagePartnerDigibytePKHOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerDigibytePKHOffset incorrect";
 		dataByteBuffer.putLong(32L);
 
-		// Index into data segment of partner's Litecoin PKH, used by GET_B_IND
-		assert dataByteBuffer.position() == addrPartnerLitecoinPKHPointer * MachineState.VALUE_SIZE : "addrPartnerLitecoinPKHPointer incorrect";
-		dataByteBuffer.putLong(addrPartnerLitecoinPKH);
+		// Index into data segment of partner's Digibyte PKH, used by GET_B_IND
+		assert dataByteBuffer.position() == addrPartnerDigibytePKHPointer * MachineState.VALUE_SIZE : "addrPartnerDigibytePKHPointer incorrect";
+		dataByteBuffer.putLong(addrPartnerDigibytePKH);
 
 		// Offset into 'trade' MESSAGE data payload for extracting hash-of-secret-A
 		assert dataByteBuffer.position() == addrTradeMessageHashOfSecretAOffset * MachineState.VALUE_SIZE : "addrTradeMessageHashOfSecretAOffset incorrect";
@@ -337,6 +341,9 @@ public class LitecoinACCTv2 implements ACCT {
 				// Use AT creation 'timestamp' as starting point for finding transactions sent to AT
 				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_CREATION_TIMESTAMP, addrLastTxnTimestamp));
 
+				/* NOP - to ensure DIGIBYTE ACCT is unique */
+				codeByteBuffer.put(OpCode.NOP.compile());
+
 				// Load B register with AT creator's address so we can save it into addrCreatorAddress1-4
 				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_CREATOR_INTO_B));
 				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrCreatorAddressPointer));
@@ -422,10 +429,10 @@ public class LitecoinACCTv2 implements ACCT {
 				// Save B register into data segment starting at addrQortalPartnerAddress1 (as pointed to by addrQortalPartnerAddressPointer)
 				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrQortalPartnerAddressPointer));
 
-				// Extract trade partner's Litecoin public key hash (PKH) from message into B
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerLitecoinPKHOffset));
-				// Store partner's Litecoin PKH (we only really use values from B1-B3)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerLitecoinPKHPointer));
+				// Extract trade partner's Digibyte public key hash (PKH) from message into B
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerDigibytePKHOffset));
+				// Store partner's Digibyte PKH (we only really use values from B1-B3)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerDigibytePKHPointer));
 				// Extract AT trade timeout (minutes) (from B4)
 				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrRefundTimeout));
 
@@ -458,9 +465,6 @@ public class LitecoinACCTv2 implements ACCT {
 				/* Transaction processing loop */
 				labelRedeemTxnLoop = codeByteBuffer.position();
 
-				/* Sleep until message arrives */
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
-
 				// Find next transaction to this AT since the last one (if any)
 				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
 				// If no transaction found, A will be zero. If A is zero, set addrComparator to 1, otherwise 0.
@@ -539,7 +543,7 @@ public class LitecoinACCTv2 implements ACCT {
 				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
 				codeByteBuffer.put(OpCode.FIN_IMD.compile());
 			} catch (CompilationException e) {
-				throw new IllegalStateException("Unable to compile LTC-QORT ACCT?", e);
+				throw new IllegalStateException("Unable to compile DGB-QORT ACCT?", e);
 			}
 		}
 
@@ -548,7 +552,7 @@ public class LitecoinACCTv2 implements ACCT {
 		byte[] codeBytes = new byte[codeByteBuffer.limit()];
 		codeByteBuffer.get(codeBytes);
 
-		assert Arrays.equals(Crypto.digest(codeBytes), LitecoinACCTv2.CODE_BYTES_HASH)
+		assert Arrays.equals(Crypto.digest(codeBytes), DigibyteACCTv3.CODE_BYTES_HASH)
 			: String.format("BTCACCT.CODE_BYTES_HASH mismatch: expected %s, actual %s", HashCode.fromBytes(CODE_BYTES_HASH), HashCode.fromBytes(Crypto.digest(codeBytes)));
 
 		final short ciyamAtVersion = 2;
@@ -586,7 +590,7 @@ public class LitecoinACCTv2 implements ACCT {
 
 		CrossChainTradeData tradeData = new CrossChainTradeData();
 
-		tradeData.foreignBlockchain = SupportedBlockchain.LITECOIN.name();
+		tradeData.foreignBlockchain = SupportedBlockchain.DIGIBYTE.name();
 		tradeData.acctName = NAME;
 
 		tradeData.qortalAtAddress = atAddress;
@@ -607,7 +611,7 @@ public class LitecoinACCTv2 implements ACCT {
 		tradeData.qortalCreatorTradeAddress = Base58.encode(addressBytes);
 		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
 
-		// Creator's Litecoin/foreign public key hash
+		// Creator's Digibyte/foreign public key hash
 		tradeData.creatorForeignPKH = new byte[20];
 		dataByteBuffer.get(tradeData.creatorForeignPKH);
 		dataByteBuffer.position(dataByteBuffer.position() + 32 - tradeData.creatorForeignPKH.length); // skip to 32 bytes
@@ -618,7 +622,7 @@ public class LitecoinACCTv2 implements ACCT {
 		// Redeem payout
 		tradeData.qortAmount = dataByteBuffer.getLong();
 
-		// Expected LTC amount
+		// Expected DGB amount
 		tradeData.expectedForeignAmount = dataByteBuffer.getLong();
 
 		// Trade timeout
@@ -642,10 +646,10 @@ public class LitecoinACCTv2 implements ACCT {
 		// Skip pointer to message sender
 		dataByteBuffer.position(dataByteBuffer.position() + 8);
 
-		// Skip 'trade' message data offset for partner's Litecoin PKH
+		// Skip 'trade' message data offset for partner's Digibyte PKH
 		dataByteBuffer.position(dataByteBuffer.position() + 8);
 
-		// Skip pointer to partner's Litecoin PKH
+		// Skip pointer to partner's Digibyte PKH
 		dataByteBuffer.position(dataByteBuffer.position() + 8);
 
 		// Skip 'trade' message data offset for hash-of-secret-A
@@ -711,10 +715,10 @@ public class LitecoinACCTv2 implements ACCT {
 		dataByteBuffer.get(hashOfSecretA);
 		dataByteBuffer.position(dataByteBuffer.position() + 32 - hashOfSecretA.length); // skip to 32 bytes
 
-		// Potential partner's Litecoin PKH
-		byte[] partnerLitecoinPKH = new byte[20];
-		dataByteBuffer.get(partnerLitecoinPKH);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerLitecoinPKH.length); // skip to 32 bytes
+		// Potential partner's Digibyte PKH
+		byte[] partnerDigibytePKH = new byte[20];
+		dataByteBuffer.get(partnerDigibytePKH);
+		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerDigibytePKH.length); // skip to 32 bytes
 
 		// Partner's receiving address (if present)
 		byte[] partnerReceivingAddress = new byte[25];
@@ -733,7 +737,7 @@ public class LitecoinACCTv2 implements ACCT {
 			tradeData.tradeRefundHeight = new Timestamp(tradeRefundTimestamp).blockHeight;
 			tradeData.qortalPartnerAddress = qortalRecipient;
 			tradeData.hashOfSecretA = hashOfSecretA;
-			tradeData.partnerForeignPKH = partnerLitecoinPKH;
+			tradeData.partnerForeignPKH = partnerDigibytePKH;
 			tradeData.lockTimeA = lockTimeA;
 
 			if (mode == AcctMode.REDEEMED)
@@ -759,7 +763,7 @@ public class LitecoinACCTv2 implements ACCT {
 			return null;
 
 		OfferMessageData offerMessageData = new OfferMessageData();
-		offerMessageData.partnerLitecoinPKH = Arrays.copyOfRange(messageData, 0, 20);
+		offerMessageData.partnerDigibytePKH = Arrays.copyOfRange(messageData, 0, 20);
 		offerMessageData.hashOfSecretA = Arrays.copyOfRange(messageData, 20, 40);
 		offerMessageData.lockTimeA = BitTwiddling.longFromBEBytes(messageData, 40);
 

src/main/java/org/qortal/crosschain/Dogecoin.java

@@ -135,6 +135,8 @@ public class Dogecoin extends Bitcoiny {
 			Context bitcoinjContext = new Context(dogecoinNet.getParams());
 
 			instance = new Dogecoin(dogecoinNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;

src/main/java/org/qortal/crosschain/ElectrumX.java

@@ -11,6 +11,7 @@ import java.util.regex.Pattern;
 
 import javax.net.ssl.SSLSocketFactory;
 
+import cash.z.wallet.sdk.rpc.CompactFormats.*;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.json.simple.JSONArray;
@@ -107,6 +108,7 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 	private final String netId;
 	private final String expectedGenesisHash;
 	private final Map<Server.ConnectionType, Integer> defaultPorts = new EnumMap<>(Server.ConnectionType.class);
+	private Bitcoiny blockchain;
 
 	private final Object serverLock = new Object();
 	private Server currentServer;
@@ -135,6 +137,11 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 
 	// Methods for use by other classes
 
+	@Override
+	public void setBlockchain(Bitcoiny blockchain) {
+		this.blockchain = blockchain;
+	}
+
 	@Override
 	public String getNetId() {
 		return this.netId;
@@ -161,6 +168,16 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 		return ((Long) heightObj).intValue();
 	}
 
+	/**
+	 * Returns list of raw blocks, starting from <tt>startHeight</tt> inclusive.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public List<CompactBlock> getCompactBlocks(int startHeight, int count) throws ForeignBlockchainException {
+		throw new ForeignBlockchainException("getCompactBlocks not implemented for ElectrumX due to being specific to zcash");
+	}
+
 	/**
 	 * Returns list of raw block headers, starting from <tt>startHeight</tt> inclusive.
 	 * <p>
@@ -222,6 +239,17 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 		return rawBlockHeaders;
 	}
 
+	/**
+	 * Returns list of raw block timestamps, starting from <tt>startHeight</tt> inclusive.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public List<Long> getBlockTimestamps(int startHeight, int count) throws ForeignBlockchainException {
+		// FUTURE: implement this if needed. For now we use getRawBlockHeaders directly
+		throw new ForeignBlockchainException("getBlockTimestamps not yet implemented for ElectrumX");
+	}
+
 	/**
 	 * Returns confirmed balance, based on passed payment script.
 	 * <p>
@@ -247,6 +275,29 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 		return (Long) balanceJson.get("confirmed");
 	}
 
+	/**
+	 * Returns confirmed balance, based on passed base58 encoded address.
+	 * <p>
+	 * @return confirmed balance, or zero if address unknown
+	 * @throws ForeignBlockchainException if there was an error
+	 */
+	@Override
+	public long getConfirmedAddressBalance(String base58Address) throws ForeignBlockchainException {
+		throw new ForeignBlockchainException("getConfirmedAddressBalance not yet implemented for ElectrumX");
+	}
+
+	/**
+	 * Returns list of unspent outputs pertaining to passed address.
+	 * <p>
+	 * @return list of unspent outputs, or empty list if address unknown
+	 * @throws ForeignBlockchainException if there was an error.
+	 */
+	@Override
+	public List<UnspentOutput> getUnspentOutputs(String address, boolean includeUnconfirmed) throws ForeignBlockchainException {
+		byte[] script = this.blockchain.addressToScriptPubKey(address);
+		return this.getUnspentOutputs(script, includeUnconfirmed);
+	}
+
 	/**
 	 * Returns list of unspent outputs pertaining to passed payment script.
 	 * <p>
@@ -482,6 +533,12 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 		return transactionHashes;
 	}
 
+	@Override
+	public List<BitcoinyTransaction> getAddressBitcoinyTransactions(String address, boolean includeUnconfirmed) throws ForeignBlockchainException {
+		// FUTURE: implement this if needed. For now we use getAddressTransactions() + getTransaction()
+		throw new ForeignBlockchainException("getAddressBitcoinyTransactions not yet implemented for ElectrumX");
+	}
+
 	/**
 	 * Broadcasts raw transaction to network.
 	 * <p>
@@ -682,6 +739,10 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 		} catch (IOException | NoSuchElementException e) {
 			// Unable to send, or receive -- try another server?
 			return null;
+		} catch (NoSuchMethodError e) {
+			// Likely an SSL dependency issue - retries are unlikely to succeed
+			LOGGER.error("ElectrumX output stream error", e);
+			return null;
 		}
 
 		long endTime = System.currentTimeMillis();

src/main/java/org/qortal/crosschain/LegacyZcashAddress.java

@@ -0,0 +1,254 @@
+/*
+ * Copyright 2011 Google Inc.
+ * Copyright 2014 Giannis Dzegoutanis
+ * Copyright 2015 Andreas Schildbach
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Updated for Zcash in May 2022 by Qortal core dev team. Modifications allow
+* correct encoding of P2SH (t3) addresses only. */
+
+package org.qortal.crosschain;
+
+import org.bitcoinj.core.*;
+import org.bitcoinj.params.Networks;
+import org.bitcoinj.script.Script.ScriptType;
+
+import javax.annotation.Nullable;
+import java.util.Arrays;
+import java.util.Objects;
+
+/**
+ * <p>A Bitcoin address looks like 1MsScoe2fTJoq4ZPdQgqyhgWeoNamYPevy and is derived from an elliptic curve public key
+ * plus a set of network parameters. Not to be confused with a {@link PeerAddress} or {@link AddressMessage}
+ * which are about network (TCP) addresses.</p>
+ *
+ * <p>A standard address is built by taking the RIPE-MD160 hash of the public key bytes, with a version prefix and a
+ * checksum suffix, then encoding it textually as base58. The version prefix is used to both denote the network for
+ * which the address is valid (see {@link NetworkParameters}, and also to indicate how the bytes inside the address
+ * should be interpreted. Whilst almost all addresses today are hashes of public keys, another (currently unsupported
+ * type) can contain a hash of a script instead.</p>
+ */
+public class LegacyZcashAddress extends Address {
+    /**
+     * An address is a RIPEMD160 hash of a public key, therefore is always 160 bits or 20 bytes.
+     */
+    public static final int LENGTH = 20;
+
+    /** True if P2SH, false if P2PKH. */
+    public final boolean p2sh;
+
+    /* Zcash P2SH header bytes */
+    private static int P2SH_HEADER_1 = 28;
+    private static int P2SH_HEADER_2 = 189;
+
+    /**
+     * Private constructor. Use {@link #fromBase58(NetworkParameters, String)},
+     * {@link #fromPubKeyHash(NetworkParameters, byte[])}, {@link #fromScriptHash(NetworkParameters, byte[])} or
+     * {@link #fromKey(NetworkParameters, ECKey)}.
+     * 
+     * @param params
+     *            network this address is valid for
+     * @param p2sh
+     *            true if hash160 is hash of a script, false if it is hash of a pubkey
+     * @param hash160
+     *            20-byte hash of pubkey or script
+     */
+    private LegacyZcashAddress(NetworkParameters params, boolean p2sh, byte[] hash160) throws AddressFormatException {
+        super(params, hash160);
+        if (hash160.length != 20)
+            throw new AddressFormatException.InvalidDataLength(
+                    "Legacy addresses are 20 byte (160 bit) hashes, but got: " + hash160.length);
+        this.p2sh = p2sh;
+    }
+
+    /**
+     * Construct a {@link LegacyZcashAddress} that represents the given pubkey hash. The resulting address will be a P2PKH type of
+     * address.
+     * 
+     * @param params
+     *            network this address is valid for
+     * @param hash160
+     *            20-byte pubkey hash
+     * @return constructed address
+     */
+    public static LegacyZcashAddress fromPubKeyHash(NetworkParameters params, byte[] hash160) throws AddressFormatException {
+        return new LegacyZcashAddress(params, false, hash160);
+    }
+
+    /**
+     * Construct a {@link LegacyZcashAddress} that represents the public part of the given {@link ECKey}. Note that an address is
+     * derived from a hash of the public key and is not the public key itself.
+     * 
+     * @param params
+     *            network this address is valid for
+     * @param key
+     *            only the public part is used
+     * @return constructed address
+     */
+    public static LegacyZcashAddress fromKey(NetworkParameters params, ECKey key) {
+        return fromPubKeyHash(params, key.getPubKeyHash());
+    }
+
+    /**
+     * Construct a {@link LegacyZcashAddress} that represents the given P2SH script hash.
+     * 
+     * @param params
+     *            network this address is valid for
+     * @param hash160
+     *            P2SH script hash
+     * @return constructed address
+     */
+    public static LegacyZcashAddress fromScriptHash(NetworkParameters params, byte[] hash160) throws AddressFormatException {
+        return new LegacyZcashAddress(params, true, hash160);
+    }
+
+    /**
+     * Construct a {@link LegacyZcashAddress} from its base58 form.
+     * 
+     * @param params
+     *            expected network this address is valid for, or null if if the network should be derived from the
+     *            base58
+     * @param base58
+     *            base58-encoded textual form of the address
+     * @throws AddressFormatException
+     *             if the given base58 doesn't parse or the checksum is invalid
+     * @throws AddressFormatException.WrongNetwork
+     *             if the given address is valid but for a different chain (eg testnet vs mainnet)
+     */
+    public static LegacyZcashAddress fromBase58(@Nullable NetworkParameters params, String base58)
+            throws AddressFormatException, AddressFormatException.WrongNetwork {
+        byte[] versionAndDataBytes = Base58.decodeChecked(base58);
+        int version = versionAndDataBytes[0] & 0xFF;
+        byte[] bytes = Arrays.copyOfRange(versionAndDataBytes, 1, versionAndDataBytes.length);
+        if (params == null) {
+            for (NetworkParameters p : Networks.get()) {
+                if (version == p.getAddressHeader())
+                    return new LegacyZcashAddress(p, false, bytes);
+                else if (version == p.getP2SHHeader())
+                    return new LegacyZcashAddress(p, true, bytes);
+            }
+            throw new AddressFormatException.InvalidPrefix("No network found for " + base58);
+        } else {
+            if (version == params.getAddressHeader())
+                return new LegacyZcashAddress(params, false, bytes);
+            else if (version == params.getP2SHHeader())
+                return new LegacyZcashAddress(params, true, bytes);
+            throw new AddressFormatException.WrongNetwork(version);
+        }
+    }
+
+    /**
+     * Get the version header of an address. This is the first byte of a base58 encoded address.
+     * 
+     * @return version header as one byte
+     */
+    public int getVersion() {
+        return p2sh ? params.getP2SHHeader() : params.getAddressHeader();
+    }
+
+    /**
+     * Returns the base58-encoded textual form, including version and checksum bytes.
+     * 
+     * @return textual form
+     */
+    public String toBase58() {
+        return this.encodeChecked(getVersion(), bytes);
+    }
+
+    /** The (big endian) 20 byte hash that is the core of a Bitcoin address. */
+    @Override
+    public byte[] getHash() {
+        return bytes;
+    }
+
+    /**
+     * Get the type of output script that will be used for sending to the address. This is either
+     * {@link ScriptType#P2PKH} or {@link ScriptType#P2SH}.
+     * 
+     * @return type of output script
+     */
+    @Override
+    public ScriptType getOutputScriptType() {
+        return p2sh ? ScriptType.P2SH : ScriptType.P2PKH;
+    }
+
+    /**
+     * Given an address, examines the version byte and attempts to find a matching NetworkParameters. If you aren't sure
+     * which network the address is intended for (eg, it was provided by a user), you can use this to decide if it is
+     * compatible with the current wallet.
+     * 
+     * @return network the address is valid for
+     * @throws AddressFormatException if the given base58 doesn't parse or the checksum is invalid
+     */
+    public static NetworkParameters getParametersFromAddress(String address) throws AddressFormatException {
+        return LegacyZcashAddress.fromBase58(null, address).getParameters();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o)
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
+        LegacyZcashAddress other = (LegacyZcashAddress) o;
+        return super.equals(other) && this.p2sh == other.p2sh;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(super.hashCode(), p2sh);
+    }
+
+    @Override
+    public String toString() {
+        return toBase58();
+    }
+
+    @Override
+    public LegacyZcashAddress clone() throws CloneNotSupportedException {
+        return (LegacyZcashAddress) super.clone();
+    }
+
+    public static String encodeChecked(int version, byte[] payload) {
+        if (version < 0 || version > 255)
+            throw new IllegalArgumentException("Version not in range.");
+
+        // A stringified buffer is:
+        // 1 byte version + data bytes + 4 bytes check code (a truncated hash)
+        byte[] addressBytes = new byte[2 + payload.length + 4];
+        addressBytes[0] = (byte) P2SH_HEADER_1;
+        addressBytes[1] = (byte) P2SH_HEADER_2;
+        System.arraycopy(payload, 0, addressBytes, 2, payload.length);
+        byte[] checksum = Sha256Hash.hashTwice(addressBytes, 0, payload.length + 2);
+        System.arraycopy(checksum, 0, addressBytes, payload.length + 2, 4);
+        return Base58.encode(addressBytes);
+    }
+
+//    // Comparator for LegacyAddress, left argument must be LegacyAddress, right argument can be any Address
+//    private static final Comparator<Address> LEGACY_ADDRESS_COMPARATOR = Address.PARTIAL_ADDRESS_COMPARATOR
+//            .thenComparingInt(a -> ((LegacyZcashAddress) a).getVersion())                    // Then compare Legacy address version byte
+//            .thenComparing(a -> a.bytes, UnsignedBytes.lexicographicalComparator());    // Then compare Legacy bytes
+//
+//    /**
+//     * {@inheritDoc}
+//     *
+//     * @param o other {@code Address} object
+//     * @return comparison result
+//     */
+//    @Override
+//    public int compareTo(Address o) {
+//       return LEGACY_ADDRESS_COMPARATOR.compare(this, o);
+//    }
+}

src/main/java/org/qortal/crosschain/Litecoin.java

@@ -145,6 +145,8 @@ public class Litecoin extends Bitcoiny {
 			Context bitcoinjContext = new Context(litecoinNet.getParams());
 
 			instance = new Litecoin(litecoinNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;

src/main/java/org/qortal/crosschain/PirateChain.java

@@ -0,0 +1,659 @@
+package org.qortal.crosschain;
+
+import cash.z.wallet.sdk.rpc.CompactFormats;
+import com.google.common.hash.HashCode;
+import com.rust.litewalletjni.LiteWalletJni;
+import org.bitcoinj.core.*;
+import org.bitcoinj.crypto.ChildNumber;
+import org.bitcoinj.crypto.DeterministicKey;
+import org.bitcoinj.script.Script;
+import org.bitcoinj.script.ScriptBuilder;
+import org.bitcoinj.wallet.DeterministicKeyChain;
+import org.bitcoinj.wallet.Wallet;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.libdohj.params.LitecoinRegTestParams;
+import org.libdohj.params.LitecoinTestNet3Params;
+import org.libdohj.params.PirateChainMainNetParams;
+import org.qortal.api.model.crosschain.PirateChainSendRequest;
+import org.qortal.controller.PirateChainWalletController;
+import org.qortal.crosschain.PirateLightClient.Server;
+import org.qortal.crosschain.PirateLightClient.Server.ConnectionType;
+import org.qortal.crypto.Crypto;
+import org.qortal.settings.Settings;
+import org.qortal.transform.TransformationException;
+import org.qortal.utils.BitTwiddling;
+
+import java.nio.ByteBuffer;
+import java.util.*;
+
+public class PirateChain extends Bitcoiny {
+
+	public static final String CURRENCY_CODE = "ARRR";
+
+	private static final Coin DEFAULT_FEE_PER_KB = Coin.valueOf(10000); // 0.0001 ARRR per 1000 bytes
+
+	private static final long MINIMUM_ORDER_AMOUNT = 10000; // 0.0001 ARRR minimum order, to avoid dust errors // TODO: increase this
+
+	// Temporary values until a dynamic fee system is written.
+	private static final long MAINNET_FEE = 10000L; // 0.0001 ARRR
+	private static final long NON_MAINNET_FEE = 10000L; // 0.0001 ARRR
+
+	private static final Map<ConnectionType, Integer> DEFAULT_LITEWALLET_PORTS = new EnumMap<>(ConnectionType.class);
+	static {
+		DEFAULT_LITEWALLET_PORTS.put(ConnectionType.TCP, 9067);
+		DEFAULT_LITEWALLET_PORTS.put(ConnectionType.SSL, 443);
+	}
+
+	public enum PirateChainNet {
+		MAIN {
+			@Override
+			public NetworkParameters getParams() {
+				return PirateChainMainNetParams.get();
+			}
+
+			@Override
+			public Collection<Server> getServers() {
+				return Arrays.asList(
+						// Servers chosen on NO BASIS WHATSOEVER from various sources!
+						new Server("arrrlightd.qortal.online", ConnectionType.SSL, 443),
+						new Server("arrrlightd1.qortal.online", ConnectionType.SSL, 443),
+						new Server("arrrlightd2.qortal.online", ConnectionType.SSL, 443),
+						new Server("lightd.pirate.black", ConnectionType.SSL, 443));
+			}
+
+			@Override
+			public String getGenesisHash() {
+				return "027e3758c3a65b12aa1046462b486d0a63bfa1beae327897f56c5cfb7daaae71";
+			}
+
+			@Override
+			public long getP2shFee(Long timestamp) {
+				// TODO: This will need to be replaced with something better in the near future!
+				return MAINNET_FEE;
+			}
+		},
+		TEST3 {
+			@Override
+			public NetworkParameters getParams() {
+				return LitecoinTestNet3Params.get();
+			}
+
+			@Override
+			public Collection<Server> getServers() {
+				return Arrays.asList();
+			}
+
+			@Override
+			public String getGenesisHash() {
+				return "4966625a4b2851d9fdee139e56211a0d88575f59ed816ff5e6a63deb4e3e29a0";
+			}
+
+			@Override
+			public long getP2shFee(Long timestamp) {
+				return NON_MAINNET_FEE;
+			}
+		},
+		REGTEST {
+			@Override
+			public NetworkParameters getParams() {
+				return LitecoinRegTestParams.get();
+			}
+
+			@Override
+			public Collection<Server> getServers() {
+				return Arrays.asList(
+						new Server("localhost", ConnectionType.TCP, 9067),
+						new Server("localhost", ConnectionType.SSL, 443));
+			}
+
+			@Override
+			public String getGenesisHash() {
+				// This is unique to each regtest instance
+				return null;
+			}
+
+			@Override
+			public long getP2shFee(Long timestamp) {
+				return NON_MAINNET_FEE;
+			}
+		};
+
+		public abstract NetworkParameters getParams();
+		public abstract Collection<Server> getServers();
+		public abstract String getGenesisHash();
+		public abstract long getP2shFee(Long timestamp) throws ForeignBlockchainException;
+	}
+
+	private static PirateChain instance;
+
+	private final PirateChainNet pirateChainNet;
+
+	// Constructors and instance
+
+	private PirateChain(PirateChainNet pirateChainNet, BitcoinyBlockchainProvider blockchain, Context bitcoinjContext, String currencyCode) {
+		super(blockchain, bitcoinjContext, currencyCode);
+		this.pirateChainNet = pirateChainNet;
+
+		LOGGER.info(() -> String.format("Starting Pirate Chain support using %s", this.pirateChainNet.name()));
+	}
+
+	public static synchronized PirateChain getInstance() {
+		if (instance == null) {
+			PirateChainNet pirateChainNet = Settings.getInstance().getPirateChainNet();
+
+			BitcoinyBlockchainProvider pirateLightClient = new PirateLightClient("PirateChain-" + pirateChainNet.name(), pirateChainNet.getGenesisHash(), pirateChainNet.getServers(), DEFAULT_LITEWALLET_PORTS);
+			Context bitcoinjContext = new Context(pirateChainNet.getParams());
+
+			instance = new PirateChain(pirateChainNet, pirateLightClient, bitcoinjContext, CURRENCY_CODE);
+
+			pirateLightClient.setBlockchain(instance);
+		}
+
+		return instance;
+	}
+
+	// Getters & setters
+
+	public static synchronized void resetForTesting() {
+		instance = null;
+	}
+
+	// Actual useful methods for use by other classes
+
+	/** Default Litecoin fee is lower than Bitcoin: only 10sats/byte. */
+	@Override
+	public Coin getFeePerKb() {
+		return DEFAULT_FEE_PER_KB;
+	}
+
+	@Override
+	public long getMinimumOrderAmount() {
+		return MINIMUM_ORDER_AMOUNT;
+	}
+
+	/**
+	 * Returns estimated LTC fee, in sats per 1000bytes, optionally for historic timestamp.
+	 * 
+	 * @param timestamp optional milliseconds since epoch, or null for 'now'
+	 * @return sats per 1000bytes, or throws ForeignBlockchainException if something went wrong
+	 */
+	@Override
+	public long getP2shFee(Long timestamp) throws ForeignBlockchainException {
+		return this.pirateChainNet.getP2shFee(timestamp);
+	}
+
+	/**
+	 * Returns confirmed balance, based on passed payment script.
+	 * <p>
+	 * @return confirmed balance, or zero if balance unknown
+	 * @throws ForeignBlockchainException if there was an error
+	 */
+	public long getConfirmedBalance(String base58Address) throws ForeignBlockchainException {
+		return this.blockchainProvider.getConfirmedAddressBalance(base58Address);
+	}
+
+	/**
+	 * Returns median timestamp from latest 11 blocks, in seconds.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public int getMedianBlockTime() throws ForeignBlockchainException {
+		int height = this.blockchainProvider.getCurrentHeight();
+
+		// Grab latest 11 blocks
+		List<Long> blockTimestamps = this.blockchainProvider.getBlockTimestamps(height - 11, 11);
+		if (blockTimestamps.size() < 11)
+			throw new ForeignBlockchainException("Not enough blocks to determine median block time");
+
+		// Descending order
+		blockTimestamps.sort((a, b) -> Long.compare(b, a));
+
+		// Pick median
+		return Math.toIntExact(blockTimestamps.get(5));
+	}
+
+	/**
+	 * Returns list of compact blocks
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	public List<CompactFormats.CompactBlock> getCompactBlocks(int startHeight, int count) throws ForeignBlockchainException {
+		return this.blockchainProvider.getCompactBlocks(startHeight, count);
+	}
+
+
+	@Override
+	public boolean isValidAddress(String address) {
+		// Start with some simple checks
+		if (address == null || !address.toLowerCase().startsWith("zs") || address.length() != 78) {
+			return false;
+		}
+
+		// Now try Bech32 decoding the address (which includes checksum verification)
+		try {
+			Bech32.Bech32Data decoded = Bech32.decode(address);
+			return (decoded != null && Objects.equals("zs", decoded.hrp));
+		}
+		catch (AddressFormatException e) {
+			// Invalid address, checksum failed, etc
+			return false;
+		}
+	}
+
+	@Override
+	public boolean isValidWalletKey(String walletKey) {
+		// For Pirate Chain, we only care that the key is a random string
+		// 32 characters in length, as it is used as entropy for the seed.
+		return walletKey != null && Base58.decode(walletKey).length == 32;
+	}
+
+	/** Returns 't3' prefixed P2SH address using passed redeem script. */
+	public String deriveP2shAddress(byte[] redeemScriptBytes) {
+		Context.propagate(bitcoinjContext);
+		byte[] redeemScriptHash = Crypto.hash160(redeemScriptBytes);
+		return LegacyZcashAddress.fromScriptHash(this.params, redeemScriptHash).toString();
+	}
+
+	/** Returns 'b' prefixed P2SH address using passed redeem script. */
+	public String deriveP2shAddressBPrefix(byte[] redeemScriptBytes) {
+		Context.propagate(bitcoinjContext);
+		byte[] redeemScriptHash = Crypto.hash160(redeemScriptBytes);
+		return LegacyAddress.fromScriptHash(this.params, redeemScriptHash).toString();
+	}
+
+	public Long getWalletBalance(String entropy58) throws ForeignBlockchainException {
+		synchronized (this) {
+			PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+			walletController.initWithEntropy58(entropy58);
+			walletController.ensureInitialized();
+			walletController.ensureSynchronized();
+			walletController.ensureNotNullSeed();
+
+			// Get balance
+			String response = LiteWalletJni.execute("balance", "");
+			JSONObject json = new JSONObject(response);
+			if (json.has("zbalance")) {
+				return json.getLong("zbalance");
+			}
+
+			throw new ForeignBlockchainException("Unable to determine balance");
+		}
+	}
+
+	public List<SimpleTransaction> getWalletTransactions(String entropy58) throws ForeignBlockchainException {
+		synchronized (this) {
+			PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+			walletController.initWithEntropy58(entropy58);
+			walletController.ensureInitialized();
+			walletController.ensureSynchronized();
+			walletController.ensureNotNullSeed();
+
+			List<SimpleTransaction> transactions = new ArrayList<>();
+
+			// Get transactions list
+			String response = LiteWalletJni.execute("list", "");
+			JSONArray transactionsJson = new JSONArray(response);
+			if (transactionsJson != null) {
+				for (int i = 0; i < transactionsJson.length(); i++) {
+					JSONObject transactionJson = transactionsJson.getJSONObject(i);
+
+					if (transactionJson.has("txid")) {
+						String txId = transactionJson.getString("txid");
+						Long timestamp = transactionJson.getLong("datetime");
+						Long amount = transactionJson.getLong("amount");
+						Long fee = transactionJson.getLong("fee");
+						String memo = null;
+
+						if (transactionJson.has("incoming_metadata")) {
+							JSONArray incomingMetadatas = transactionJson.getJSONArray("incoming_metadata");
+							if (incomingMetadatas != null) {
+								for (int j = 0; j < incomingMetadatas.length(); j++) {
+									JSONObject incomingMetadata = incomingMetadatas.getJSONObject(j);
+									if (incomingMetadata.has("value")) {
+										//String address = incomingMetadata.getString("address");
+										Long value = incomingMetadata.getLong("value");
+										amount = value; // TODO: figure out how to parse transactions with multiple incomingMetadata entries
+									}
+
+									if (incomingMetadata.has("memo") && !incomingMetadata.isNull("memo")) {
+										memo = incomingMetadata.getString("memo");
+									}
+								}
+							}
+						}
+
+						if (transactionJson.has("outgoing_metadata")) {
+							JSONArray outgoingMetadatas = transactionJson.getJSONArray("outgoing_metadata");
+							for (int j = 0; j < outgoingMetadatas.length(); j++) {
+								JSONObject outgoingMetadata = outgoingMetadatas.getJSONObject(j);
+
+								if (outgoingMetadata.has("memo") && !outgoingMetadata.isNull("memo")) {
+									memo = outgoingMetadata.getString("memo");
+								}
+							}
+						}
+
+						long timestampMillis = Math.toIntExact(timestamp) * 1000L;
+						SimpleTransaction transaction = new SimpleTransaction(txId, timestampMillis, amount, fee, null, null, memo);
+						transactions.add(transaction);
+					}
+				}
+			}
+
+			return transactions;
+		}
+	}
+
+	public String getWalletAddress(String entropy58) throws ForeignBlockchainException {
+		synchronized (this) {
+			PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+			walletController.initWithEntropy58(entropy58);
+			walletController.ensureInitialized();
+			walletController.ensureNotNullSeed();
+
+			return walletController.getCurrentWallet().getWalletAddress();
+		}
+	}
+
+	public String getUnusedReceiveAddress(String key58) throws ForeignBlockchainException {
+		// For now, return the main wallet address
+		// FUTURE: generate an unused one
+		return this.getWalletAddress(key58);
+	}
+
+	public String sendCoins(PirateChainSendRequest pirateChainSendRequest) throws ForeignBlockchainException {
+		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+		walletController.initWithEntropy58(pirateChainSendRequest.entropy58);
+		walletController.ensureInitialized();
+		walletController.ensureSynchronized();
+		walletController.ensureNotNullSeed();
+
+		// Unlock wallet
+		walletController.getCurrentWallet().unlock();
+
+		// Build spend
+		JSONObject txn = new JSONObject();
+		txn.put("input", walletController.getCurrentWallet().getWalletAddress());
+		txn.put("fee", MAINNET_FEE);
+
+		JSONObject output = new JSONObject();
+		output.put("address", pirateChainSendRequest.receivingAddress);
+		output.put("amount", pirateChainSendRequest.arrrAmount);
+		output.put("memo", pirateChainSendRequest.memo);
+
+		JSONArray outputs = new JSONArray();
+		outputs.put(output);
+		txn.put("output", outputs);
+
+		String txnString = txn.toString();
+
+		// Send the coins
+		String response = LiteWalletJni.execute("send", txnString);
+		JSONObject json = new JSONObject(response);
+		try {
+			if (json.has("txid")) { // Success
+				return json.getString("txid");
+			}
+			else if (json.has("error")) {
+				String error = json.getString("error");
+				throw new ForeignBlockchainException(error);
+			}
+
+		} catch (JSONException e) {
+			throw new ForeignBlockchainException(e.getMessage());
+		}
+
+		throw new ForeignBlockchainException("Something went wrong");
+	}
+
+	public String fundP2SH(String entropy58, String receivingAddress, long amount,
+						   String redeemScript58) throws ForeignBlockchainException {
+
+		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+		walletController.initWithEntropy58(entropy58);
+		walletController.ensureInitialized();
+		walletController.ensureSynchronized();
+		walletController.ensureNotNullSeed();
+
+		// Unlock wallet
+		walletController.getCurrentWallet().unlock();
+
+		// Build spend
+		JSONObject txn = new JSONObject();
+		txn.put("input", walletController.getCurrentWallet().getWalletAddress());
+		txn.put("fee", MAINNET_FEE);
+
+		JSONObject output = new JSONObject();
+		output.put("address", receivingAddress);
+		output.put("amount", amount);
+		//output.put("memo", memo);
+
+		JSONArray outputs = new JSONArray();
+		outputs.put(output);
+		txn.put("output", outputs);
+		txn.put("script", redeemScript58);
+
+		String txnString = txn.toString();
+
+		// Send the coins
+		String response = LiteWalletJni.execute("sendp2sh", txnString);
+		JSONObject json = new JSONObject(response);
+		try {
+			if (json.has("txid")) { // Success
+				return json.getString("txid");
+			}
+			else if (json.has("error")) {
+				String error = json.getString("error");
+				throw new ForeignBlockchainException(error);
+			}
+
+		} catch (JSONException e) {
+			throw new ForeignBlockchainException(e.getMessage());
+		}
+
+		throw new ForeignBlockchainException("Something went wrong");
+	}
+
+	public String redeemP2sh(String p2shAddress, String receivingAddress, long amount, String redeemScript58,
+							 String fundingTxid58, String secret58, String privateKey58) throws ForeignBlockchainException {
+
+		// Use null seed wallet since we may not have the entropy bytes for a real wallet's seed
+		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+		walletController.initNullSeedWallet();
+		walletController.ensureInitialized();
+
+		walletController.getCurrentWallet().unlock();
+
+		// Build spend
+		JSONObject txn = new JSONObject();
+		txn.put("input", p2shAddress);
+		txn.put("fee", MAINNET_FEE);
+
+		JSONObject output = new JSONObject();
+		output.put("address", receivingAddress);
+		output.put("amount", amount);
+		// output.put("memo", ""); // Maybe useful in future to include trade details?
+
+		JSONArray outputs = new JSONArray();
+		outputs.put(output);
+		txn.put("output", outputs);
+
+		txn.put("script", redeemScript58);
+		txn.put("txid", fundingTxid58);
+		txn.put("locktime", 0); // Must be 0 when redeeming
+		txn.put("secret", secret58);
+		txn.put("privkey", privateKey58);
+
+		String txnString = txn.toString();
+
+		// Redeem the P2SH
+		String response = LiteWalletJni.execute("redeemp2sh", txnString);
+		JSONObject json = new JSONObject(response);
+		try {
+			if (json.has("txid")) { // Success
+				return json.getString("txid");
+			}
+			else if (json.has("error")) {
+				String error = json.getString("error");
+				throw new ForeignBlockchainException(error);
+			}
+
+		} catch (JSONException e) {
+			throw new ForeignBlockchainException(e.getMessage());
+		}
+
+		throw new ForeignBlockchainException("Something went wrong");
+	}
+
+	public String refundP2sh(String p2shAddress, String receivingAddress, long amount, String redeemScript58,
+							 String fundingTxid58, int lockTime, String privateKey58) throws ForeignBlockchainException {
+
+		// Use null seed wallet since we may not have the entropy bytes for a real wallet's seed
+		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+		walletController.initNullSeedWallet();
+		walletController.ensureInitialized();
+
+		walletController.getCurrentWallet().unlock();
+
+		// Build spend
+		JSONObject txn = new JSONObject();
+		txn.put("input", p2shAddress);
+		txn.put("fee", MAINNET_FEE);
+
+		JSONObject output = new JSONObject();
+		output.put("address", receivingAddress);
+		output.put("amount", amount);
+		// output.put("memo", ""); // Maybe useful in future to include trade details?
+
+		JSONArray outputs = new JSONArray();
+		outputs.put(output);
+		txn.put("output", outputs);
+
+		txn.put("script", redeemScript58);
+		txn.put("txid", fundingTxid58);
+		txn.put("locktime", lockTime);
+		txn.put("secret", ""); // Must be blank when refunding
+		txn.put("privkey", privateKey58);
+
+		String txnString = txn.toString();
+
+		// Redeem the P2SH
+		String response = LiteWalletJni.execute("redeemp2sh", txnString);
+		JSONObject json = new JSONObject(response);
+		try {
+			if (json.has("txid")) { // Success
+				return json.getString("txid");
+			}
+			else if (json.has("error")) {
+				String error = json.getString("error");
+				throw new ForeignBlockchainException(error);
+			}
+
+		} catch (JSONException e) {
+			throw new ForeignBlockchainException(e.getMessage());
+		}
+
+		throw new ForeignBlockchainException("Something went wrong");
+	}
+
+	public String getSyncStatus(String entropy58) throws ForeignBlockchainException {
+		synchronized (this) {
+			PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+			walletController.initWithEntropy58(entropy58);
+
+			return walletController.getSyncStatus();
+		}
+	}
+
+	public static BitcoinyTransaction deserializeRawTransaction(String rawTransactionHex) throws TransformationException {
+		byte[] rawTransactionData = HashCode.fromString(rawTransactionHex).asBytes();
+		ByteBuffer byteBuffer = ByteBuffer.wrap(rawTransactionData);
+
+		// Header
+		int header = BitTwiddling.readU32(byteBuffer);
+		boolean overwintered = ((header >> 31 & 0xff) == 255);
+		int version = header & 0x7FFFFFFF;
+
+		// Version group ID
+		int versionGroupId = 0;
+		if (overwintered) {
+			versionGroupId = BitTwiddling.readU32(byteBuffer);
+		}
+
+		boolean isOverwinterV3 = overwintered && versionGroupId == 0x03C48270 && version == 3;
+		boolean isSaplingV4 = overwintered && versionGroupId == 0x892F2085 && version == 4;
+		if (overwintered && !(isOverwinterV3 || isSaplingV4)) {
+			throw new TransformationException("Unknown transaction format");
+		}
+
+		// Inputs
+		List<BitcoinyTransaction.Input> inputs = new ArrayList<>();
+		int vinCount = BitTwiddling.readU8(byteBuffer);
+		for (int i=0; i<vinCount; i++) {
+			// Outpoint hash
+			byte[] outpointHashBytes = new byte[32];
+			byteBuffer.get(outpointHashBytes);
+			String outpointHash = HashCode.fromBytes(outpointHashBytes).toString();
+
+			// vout
+			int vout = BitTwiddling.readU32(byteBuffer);
+
+			// scriptSig
+			int scriptSigLength = BitTwiddling.readU8(byteBuffer);
+			byte[] scriptSigBytes = new byte[scriptSigLength];
+			byteBuffer.get(scriptSigBytes);
+			String scriptSig = HashCode.fromBytes(scriptSigBytes).toString();
+
+			int sequence = BitTwiddling.readU32(byteBuffer);
+
+			BitcoinyTransaction.Input input = new BitcoinyTransaction.Input(scriptSig, sequence, outpointHash, vout);
+			inputs.add(input);
+		}
+
+		// Outputs
+		List<BitcoinyTransaction.Output> outputs = new ArrayList<>();
+		int voutCount = BitTwiddling.readU8(byteBuffer);
+		for (int i=0; i<voutCount; i++) {
+			// Amount
+			byte[] amountBytes = new byte[8];
+			byteBuffer.get(amountBytes);
+			long amount = BitTwiddling.longFromLEBytes(amountBytes, 0);
+
+			// Script pubkey
+			int scriptPubkeySize = BitTwiddling.readU8(byteBuffer);
+			byte[] scriptPubkeyBytes = new byte[scriptPubkeySize];
+			byteBuffer.get(scriptPubkeyBytes);
+			String scriptPubKey = HashCode.fromBytes(scriptPubkeyBytes).toString();
+
+			outputs.add(new BitcoinyTransaction.Output(scriptPubKey, amount, null));
+		}
+
+		// Locktime
+		byte[] locktimeBytes = new byte[4];
+		byteBuffer.get(locktimeBytes);
+		int locktime = BitTwiddling.intFromLEBytes(locktimeBytes, 0);
+
+		// Expiry height
+		int expiryHeight = 0;
+		if (isOverwinterV3 || isSaplingV4) {
+			byte[] expiryHeightBytes = new byte[4];
+			byteBuffer.get(expiryHeightBytes);
+			expiryHeight = BitTwiddling.intFromLEBytes(expiryHeightBytes, 0);
+		}
+
+		String txHash = null; // Not present in raw transaction data
+		int size = 0; // Not present in raw transaction data
+		Integer timestamp = null; // Not present in raw transaction data
+
+		// Note: this is incomplete, as sapling spend info is not yet parsed. We don't need it for our
+		// current trade bot implementation, but it could be added in the future, for completeness.
+		// See link below for reference:
+		// https://github.com/PirateNetwork/librustzcash/blob/2981c4d2860f7cd73282fed885daac0323ff0280/zcash_primitives/src/transaction/mod.rs#L197
+
+		return new BitcoinyTransaction(txHash, size, locktime, timestamp, inputs, outputs);
+	}
+
+}

src/main/java/org/qortal/crosschain/PirateChainACCTv3.java

@@ -0,0 +1,875 @@
+package org.qortal.crosschain;
+
+import com.google.common.hash.HashCode;
+import com.google.common.primitives.Bytes;
+import org.ciyam.at.*;
+import org.qortal.account.Account;
+import org.qortal.asset.Asset;
+import org.qortal.at.QortalFunctionCode;
+import org.qortal.crypto.Crypto;
+import org.qortal.data.at.ATData;
+import org.qortal.data.at.ATStateData;
+import org.qortal.data.crosschain.CrossChainTradeData;
+import org.qortal.data.transaction.MessageTransactionData;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.utils.Base58;
+import org.qortal.utils.BitTwiddling;
+
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.List;
+
+import static org.ciyam.at.OpCode.calcOffset;
+
+/**
+ * Cross-chain trade AT
+ * 
+ * <p>
+ * <ul>
+ * <li>Bob generates PirateChain & Qortal 'trade' keys
+ * 		<ul>
+ * 			<li>private key required to sign P2SH redeem tx</li>
+ * 			<li>private key could be used to create 'secret' (e.g. double-SHA256)</li>
+ * 			<li>encrypted private key could be stored in Qortal AT for access by Bob from any node</li>
+ * 		</ul>
+ * </li>
+ * <li>Bob deploys Qortal AT
+ * 		<ul>
+ * 		</ul>
+ * </li>
+ * <li>Alice finds Qortal AT and wants to trade
+ * 		<ul>
+ * 			<li>Alice generates PirateChain & Qortal 'trade' keys</li>
+ * 			<li>Alice funds PirateChain P2SH-A</li>
+ * 			<li>Alice sends 'offer' MESSAGE to Bob from her Qortal trade address, containing:
+ * 				<ul>
+ * 					<li>hash-of-secret-A</li>
+ * 					<li>her 'trade' Pirate Chain public key</li>
+ * 				</ul>
+ * 			</li>
+ * 		</ul>
+ * </li>
+ * <li>Bob receives "offer" MESSAGE
+ * 		<ul>
+ * 			<li>Checks Alice's P2SH-A</li>
+ * 			<li>Sends 'trade' MESSAGE to Qortal AT from his trade address, containing:
+ * 				<ul>
+ * 					<li>Alice's trade Qortal address</li>
+ * 					<li>Alice's trade Pirate Chain public key</li>
+ * 					<li>hash-of-secret-A</li>
+ * 				</ul>
+ * 			</li>
+ * 		</ul>
+ * </li>
+ * <li>Alice checks Qortal AT to confirm it's locked to her
+ * 		<ul>
+ * 			<li>Alice sends 'redeem' MESSAGE to Qortal AT from her trade address, containing:
+ * 				<ul>
+ * 					<li>secret-A</li>
+ * 					<li>Qortal receiving address of her chosing</li>
+ * 				</ul>
+ * 			</li>
+ * 			<li>AT's QORT funds are sent to Qortal receiving address</li>
+ * 		</ul>
+ * </li>
+ * <li>Bob checks AT, extracts secret-A
+ * 		<ul>
+ * 			<li>Bob redeems P2SH-A using his PirateChain trade key and secret-A</li>
+ * 			<li>P2SH-A ARRR funds end up at PirateChain address determined by redeem transaction output(s)</li>
+ * 		</ul>
+ * </li>
+ * </ul>
+ */
+public class PirateChainACCTv3 implements ACCT {
+
+	public static final String NAME = PirateChainACCTv3.class.getSimpleName();
+	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("fc2818ac0819ab658a065ab0d050e75f167921e2dce5969b9b7741e47e477d83").asBytes(); // SHA256 of AT code bytes
+
+	public static final int SECRET_LENGTH = 32;
+
+	/** <b>Value</b> offset into AT segment where 'mode' variable (long) is stored. (Multiply by MachineState.VALUE_SIZE for byte offset). */
+	private static final int MODE_VALUE_OFFSET = 68;
+	/** <b>Byte</b> offset into AT state data where 'mode' variable (long) is stored. */
+	public static final int MODE_BYTE_OFFSET = MachineState.HEADER_LENGTH + (MODE_VALUE_OFFSET * MachineState.VALUE_SIZE);
+
+	public static class OfferMessageData {
+		public byte[] partnerPirateChainPublicKey;
+		public byte[] hashOfSecretA;
+		public long lockTimeA;
+	}
+	public static final int OFFER_MESSAGE_LENGTH = 33 /*partnerPirateChainPublicKey*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
+	public static final int TRADE_MESSAGE_LENGTH = 32 /*partner's Qortal trade address (padded from 25 to 32)*/
+			+ 40 /*partner's Pirate Chain public key (padded from 33 to 40)*/
+			+ 8 /*AT trade timeout (minutes)*/
+			+ 24 /*hash of secret-A (padded from 20 to 24)*/
+			+ 8 /*lockTimeA*/;
+	public static final int REDEEM_MESSAGE_LENGTH = 32 /*secret-A*/ + 32 /*partner's Qortal receiving address padded from 25 to 32*/;
+	public static final int CANCEL_MESSAGE_LENGTH = 32 /*AT creator's Qortal address*/;
+
+	private static PirateChainACCTv3 instance;
+
+	private PirateChainACCTv3() {
+	}
+
+	public static synchronized PirateChainACCTv3 getInstance() {
+		if (instance == null)
+			instance = new PirateChainACCTv3();
+
+		return instance;
+	}
+
+	@Override
+	public byte[] getCodeBytesHash() {
+		return CODE_BYTES_HASH;
+	}
+
+	@Override
+	public int getModeByteOffset() {
+		return MODE_BYTE_OFFSET;
+	}
+
+	@Override
+	public ForeignBlockchain getBlockchain() {
+		return PirateChain.getInstance();
+	}
+
+	/**
+	 * Returns Qortal AT creation bytes for cross-chain trading AT.
+	 * <p>
+	 * <tt>tradeTimeout</tt> (minutes) is the time window for the trade partner to send the
+	 * 32-byte secret to the AT, before the AT automatically refunds the AT's creator.
+	 * 
+	 * @param creatorTradeAddress AT creator's trade Qortal address
+	 * @param pirateChainPublicKeyHash 33-byte creator's trade PirateChain public key
+	 * @param qortAmount how much QORT to pay trade partner if they send correct 32-byte secrets to AT
+	 * @param arrrAmount how much ARRR the AT creator is expecting to trade
+	 * @param tradeTimeout suggested timeout for entire trade
+	 */
+	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] pirateChainPublicKeyHash, long qortAmount, long arrrAmount, int tradeTimeout) {
+		if (pirateChainPublicKeyHash.length != 33)
+			throw new IllegalArgumentException("PirateChain public key hash should be 33 bytes");
+
+		// Labels for data segment addresses
+		int addrCounter = 0;
+
+		// Constants (with corresponding dataByteBuffer.put*() calls below)
+
+		final int addrCreatorTradeAddress1 = addrCounter++;
+		final int addrCreatorTradeAddress2 = addrCounter++;
+		final int addrCreatorTradeAddress3 = addrCounter++;
+		final int addrCreatorTradeAddress4 = addrCounter++;
+
+		final int addrPirateChainPublicKeyHash = addrCounter;
+		addrCounter += 5;
+
+		final int addrQortAmount = addrCounter++;
+		final int addrarrrAmount = addrCounter++;
+		final int addrTradeTimeout = addrCounter++;
+
+		final int addrMessageTxnType = addrCounter++;
+		final int addrExpectedTradeMessageLength = addrCounter++;
+		final int addrExpectedRedeemMessageLength = addrCounter++;
+
+		final int addrCreatorAddressPointer = addrCounter++;
+		final int addrQortalPartnerAddressPointer = addrCounter++;
+		final int addrMessageSenderPointer = addrCounter++;
+
+		final int addrTradeMessagePartnerPirateChainPublicKeyFirst32BytesOffset = addrCounter++;
+		final int addrTradeMessagePartnerPirateChainPublicKeyLastByteOffset = addrCounter++; // Remainder of public key, plus timeout
+		final int addrPartnerPirateChainPublicKeyFirst32BytesPointer = addrCounter++;
+		final int addrPartnerPirateChainPublicKeyLastBytePointer = addrCounter++; // Remainder of public key
+		final int addrTradeMessageHashOfSecretAOffset = addrCounter++;
+		final int addrHashOfSecretAPointer = addrCounter++;
+
+		final int addrRedeemMessageReceivingAddressOffset = addrCounter++;
+
+		final int addrMessageDataPointer = addrCounter++;
+		final int addrMessageDataLength = addrCounter++;
+
+		final int addrPartnerReceivingAddressPointer = addrCounter++;
+
+		final int addrEndOfConstants = addrCounter;
+
+		// Variables
+
+		final int addrCreatorAddress1 = addrCounter++;
+		final int addrCreatorAddress2 = addrCounter++;
+		final int addrCreatorAddress3 = addrCounter++;
+		final int addrCreatorAddress4 = addrCounter++;
+
+		final int addrQortalPartnerAddress1 = addrCounter++;
+		final int addrQortalPartnerAddress2 = addrCounter++;
+		final int addrQortalPartnerAddress3 = addrCounter++;
+		final int addrQortalPartnerAddress4 = addrCounter++;
+
+		final int addrLockTimeA = addrCounter++;
+		final int addrRefundTimeout = addrCounter++;
+		final int addrRefundTimestamp = addrCounter++;
+		final int addrLastTxnTimestamp = addrCounter++;
+		final int addrBlockTimestamp = addrCounter++;
+		final int addrTxnType = addrCounter++;
+		final int addrResult = addrCounter++;
+
+		final int addrMessageSender1 = addrCounter++;
+		final int addrMessageSender2 = addrCounter++;
+		final int addrMessageSender3 = addrCounter++;
+		final int addrMessageSender4 = addrCounter++;
+
+		final int addrMessageLength = addrCounter++;
+
+		final int addrMessageData = addrCounter;
+		addrCounter += 4;
+
+		final int addrHashOfSecretA = addrCounter;
+		addrCounter += 4;
+
+		final int addrPartnerPirateChainPublicKeyFirst32Bytes = addrCounter;
+		addrCounter += 4;
+
+		final int addrPartnerPirateChainPublicKeyLastByte = addrCounter;
+		addrCounter += 4; // We retrieve using GET_B_IND, so need to allow space for the full 32 bytes
+
+		final int addrPartnerReceivingAddress = addrCounter;
+		addrCounter += 4;
+
+		final int addrMode = addrCounter++;
+		assert addrMode == MODE_VALUE_OFFSET : String.format("addrMode %d does not match MODE_VALUE_OFFSET %d", addrMode, MODE_VALUE_OFFSET);
+
+		// Data segment
+		ByteBuffer dataByteBuffer = ByteBuffer.allocate(addrCounter * MachineState.VALUE_SIZE);
+
+		// AT creator's trade Qortal address, decoded from Base58
+		assert dataByteBuffer.position() == addrCreatorTradeAddress1 * MachineState.VALUE_SIZE : "addrCreatorTradeAddress1 incorrect";
+		byte[] creatorTradeAddressBytes = Base58.decode(creatorTradeAddress);
+		dataByteBuffer.put(Bytes.ensureCapacity(creatorTradeAddressBytes, 32, 0));
+
+		// PirateChain public key hash
+		assert dataByteBuffer.position() == addrPirateChainPublicKeyHash * MachineState.VALUE_SIZE : "addrPirateChainPublicKeyHash incorrect";
+		dataByteBuffer.put(Bytes.ensureCapacity(pirateChainPublicKeyHash, 40, 0));
+
+		// Redeem Qort amount
+		assert dataByteBuffer.position() == addrQortAmount * MachineState.VALUE_SIZE : "addrQortAmount incorrect";
+		dataByteBuffer.putLong(qortAmount);
+
+		// Expected PirateChain amount
+		assert dataByteBuffer.position() == addrarrrAmount * MachineState.VALUE_SIZE : "addrarrrAmount incorrect";
+		dataByteBuffer.putLong(arrrAmount);
+
+		// Suggested trade timeout (minutes)
+		assert dataByteBuffer.position() == addrTradeTimeout * MachineState.VALUE_SIZE : "addrTradeTimeout incorrect";
+		dataByteBuffer.putLong(tradeTimeout);
+
+		// We're only interested in MESSAGE transactions
+		assert dataByteBuffer.position() == addrMessageTxnType * MachineState.VALUE_SIZE : "addrMessageTxnType incorrect";
+		dataByteBuffer.putLong(API.ATTransactionType.MESSAGE.value);
+
+		// Expected length of 'trade' MESSAGE data from AT creator
+		assert dataByteBuffer.position() == addrExpectedTradeMessageLength * MachineState.VALUE_SIZE : "addrExpectedTradeMessageLength incorrect";
+		dataByteBuffer.putLong(TRADE_MESSAGE_LENGTH);
+
+		// Expected length of 'redeem' MESSAGE data from trade partner
+		assert dataByteBuffer.position() == addrExpectedRedeemMessageLength * MachineState.VALUE_SIZE : "addrExpectedRedeemMessageLength incorrect";
+		dataByteBuffer.putLong(REDEEM_MESSAGE_LENGTH);
+
+		// Index into data segment of AT creator's address, used by GET_B_IND
+		assert dataByteBuffer.position() == addrCreatorAddressPointer * MachineState.VALUE_SIZE : "addrCreatorAddressPointer incorrect";
+		dataByteBuffer.putLong(addrCreatorAddress1);
+
+		// Index into data segment of partner's Qortal address, used by SET_B_IND
+		assert dataByteBuffer.position() == addrQortalPartnerAddressPointer * MachineState.VALUE_SIZE : "addrQortalPartnerAddressPointer incorrect";
+		dataByteBuffer.putLong(addrQortalPartnerAddress1);
+
+		// Index into data segment of (temporary) transaction's sender's address, used by GET_B_IND
+		assert dataByteBuffer.position() == addrMessageSenderPointer * MachineState.VALUE_SIZE : "addrMessageSenderPointer incorrect";
+		dataByteBuffer.putLong(addrMessageSender1);
+
+		// Offset into 'trade' MESSAGE data payload for extracting first 32 bytes of partner's Pirate Chain public key
+		assert dataByteBuffer.position() == addrTradeMessagePartnerPirateChainPublicKeyFirst32BytesOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerPirateChainPublicKeyFirst32BytesOffset incorrect";
+		dataByteBuffer.putLong(32L);
+
+		// Offset into 'trade' MESSAGE data payload for extracting last byte of public key
+		assert dataByteBuffer.position() == addrTradeMessagePartnerPirateChainPublicKeyLastByteOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerPirateChainPublicKeyLastByteOffset incorrect";
+		dataByteBuffer.putLong(64L);
+
+		// Index into data segment of partner's Pirate Chain public key, used by GET_B_IND
+		assert dataByteBuffer.position() == addrPartnerPirateChainPublicKeyFirst32BytesPointer * MachineState.VALUE_SIZE : "addrPartnerPirateChainPublicKeyFirst32BytesPointer incorrect";
+		dataByteBuffer.putLong(addrPartnerPirateChainPublicKeyFirst32Bytes);
+
+		// Index into data segment of remainder of partner's Pirate Chain public key, used by GET_B_IND
+		assert dataByteBuffer.position() == addrPartnerPirateChainPublicKeyLastBytePointer * MachineState.VALUE_SIZE : "addrPartnerPirateChainPublicKeyLastBytePointer incorrect";
+		dataByteBuffer.putLong(addrPartnerPirateChainPublicKeyLastByte);
+
+		// Offset into 'trade' MESSAGE data payload for extracting hash-of-secret-A
+		assert dataByteBuffer.position() == addrTradeMessageHashOfSecretAOffset * MachineState.VALUE_SIZE : "addrTradeMessageHashOfSecretAOffset incorrect";
+		dataByteBuffer.putLong(80L);
+
+		// Index into data segment to hash of secret A, used by GET_B_IND
+		assert dataByteBuffer.position() == addrHashOfSecretAPointer * MachineState.VALUE_SIZE : "addrHashOfSecretAPointer incorrect";
+		dataByteBuffer.putLong(addrHashOfSecretA);
+
+		// Offset into 'redeem' MESSAGE data payload for extracting Qortal receiving address
+		assert dataByteBuffer.position() == addrRedeemMessageReceivingAddressOffset * MachineState.VALUE_SIZE : "addrRedeemMessageReceivingAddressOffset incorrect";
+		dataByteBuffer.putLong(32L);
+
+		// Source location and length for hashing any passed secret
+		assert dataByteBuffer.position() == addrMessageDataPointer * MachineState.VALUE_SIZE : "addrMessageDataPointer incorrect";
+		dataByteBuffer.putLong(addrMessageData);
+		assert dataByteBuffer.position() == addrMessageDataLength * MachineState.VALUE_SIZE : "addrMessageDataLength incorrect";
+		dataByteBuffer.putLong(32L);
+
+		// Pointer into data segment of where to save partner's receiving Qortal address, used by GET_B_IND
+		assert dataByteBuffer.position() == addrPartnerReceivingAddressPointer * MachineState.VALUE_SIZE : "addrPartnerReceivingAddressPointer incorrect";
+		dataByteBuffer.putLong(addrPartnerReceivingAddress);
+
+		assert dataByteBuffer.position() == addrEndOfConstants * MachineState.VALUE_SIZE : "dataByteBuffer position not at end of constants";
+
+		// Code labels
+		Integer labelRefund = null;
+
+		Integer labelTradeTxnLoop = null;
+		Integer labelCheckTradeTxn = null;
+		Integer labelCheckCancelTxn = null;
+		Integer labelNotTradeNorCancelTxn = null;
+		Integer labelCheckNonRefundTradeTxn = null;
+		Integer labelTradeTxnExtract = null;
+		Integer labelRedeemTxnLoop = null;
+		Integer labelCheckRedeemTxn = null;
+		Integer labelCheckRedeemTxnSender = null;
+		Integer labelPayout = null;
+
+		ByteBuffer codeByteBuffer = ByteBuffer.allocate(768);
+
+		// Two-pass version
+		for (int pass = 0; pass < 2; ++pass) {
+			codeByteBuffer.clear();
+
+			try {
+				/* Initialization */
+
+				// Use AT creation 'timestamp' as starting point for finding transactions sent to AT
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_CREATION_TIMESTAMP, addrLastTxnTimestamp));
+
+				// Load B register with AT creator's address so we can save it into addrCreatorAddress1-4
+				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_CREATOR_INTO_B));
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrCreatorAddressPointer));
+
+				// Set restart position to after this opcode
+				codeByteBuffer.put(OpCode.SET_PCS.compile());
+
+				/* Loop, waiting for message from AT creator's trade address containing trade partner details, or AT owner's address to cancel offer */
+
+				/* Transaction processing loop */
+				labelTradeTxnLoop = codeByteBuffer.position();
+
+				/* Sleep until message arrives */
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
+
+				// Find next transaction (if any) to this AT since the last one (referenced by addrLastTxnTimestamp)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
+				// If no transaction found, A will be zero. If A is zero, set addrResult to 1, otherwise 0.
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.CHECK_A_IS_ZERO, addrResult));
+				// If addrResult is zero (i.e. A is non-zero, transaction was found) then go check transaction
+				codeByteBuffer.put(OpCode.BZR_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelCheckTradeTxn)));
+				// Stop and wait for next block
+				codeByteBuffer.put(OpCode.STP_IMD.compile());
+
+				/* Check transaction */
+				labelCheckTradeTxn = codeByteBuffer.position();
+
+				// Update our 'last found transaction's timestamp' using 'timestamp' from transaction
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TIMESTAMP_FROM_TX_IN_A, addrLastTxnTimestamp));
+				// Extract transaction type (message/payment) from transaction and save type in addrTxnType
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TYPE_FROM_TX_IN_A, addrTxnType));
+				// If transaction type is not MESSAGE type then go look for another transaction
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrTxnType, addrMessageTxnType, calcOffset(codeByteBuffer, labelTradeTxnLoop)));
+
+				/* Check transaction's sender. We're expecting AT creator's trade address for 'trade' message, or AT creator's own address for 'cancel' message. */
+
+				// Extract sender address from transaction into B register
+				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_ADDRESS_FROM_TX_IN_A_INTO_B));
+				// Save B register into data segment starting at addrMessageSender1 (as pointed to by addrMessageSenderPointer)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageSenderPointer));
+				// Compare each part of message sender's address with AT creator's trade address. If they don't match, check for cancel situation.
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrCreatorTradeAddress1, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrCreatorTradeAddress2, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrCreatorTradeAddress3, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrCreatorTradeAddress4, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
+				// Message sender's address matches AT creator's trade address so go process 'trade' message
+				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelCheckNonRefundTradeTxn == null ? 0 : labelCheckNonRefundTradeTxn));
+
+				/* Checking message sender for possible cancel message */
+				labelCheckCancelTxn = codeByteBuffer.position();
+
+				// Compare each part of message sender's address with AT creator's address. If they don't match, look for another transaction.
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrCreatorAddress1, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrCreatorAddress2, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrCreatorAddress3, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrCreatorAddress4, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
+				// Partner address is AT creator's address, so cancel offer and finish.
+				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.CANCELLED.value));
+				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
+				codeByteBuffer.put(OpCode.FIN_IMD.compile());
+
+				/* Not trade nor cancel message */
+				labelNotTradeNorCancelTxn = codeByteBuffer.position();
+
+				// Loop to find another transaction
+				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelTradeTxnLoop == null ? 0 : labelTradeTxnLoop));
+
+				/* Possible switch-to-trade-mode message */
+				labelCheckNonRefundTradeTxn = codeByteBuffer.position();
+
+				// Check 'trade' message we received has expected number of message bytes
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(QortalFunctionCode.GET_MESSAGE_LENGTH_FROM_TX_IN_A.value, addrMessageLength));
+				// If message length matches, branch to info extraction code
+				codeByteBuffer.put(OpCode.BEQ_DAT.compile(addrMessageLength, addrExpectedTradeMessageLength, calcOffset(codeByteBuffer, labelTradeTxnExtract)));
+				// Message length didn't match - go back to finding another 'trade' MESSAGE transaction
+				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelTradeTxnLoop == null ? 0 : labelTradeTxnLoop));
+
+				/* Extracting info from 'trade' MESSAGE transaction */
+				labelTradeTxnExtract = codeByteBuffer.position();
+
+				// Extract message from transaction into B register
+				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_MESSAGE_FROM_TX_IN_A_INTO_B));
+				// Save B register into data segment starting at addrQortalPartnerAddress1 (as pointed to by addrQortalPartnerAddressPointer)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrQortalPartnerAddressPointer));
+
+				// Extract first 32 bytes of trade partner's Pirate Chain public key from message into B
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerPirateChainPublicKeyFirst32BytesOffset));
+				// Store first 32 bytes of partner's Pirate Chain public key
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerPirateChainPublicKeyFirst32BytesPointer));
+
+				// Extract last byte of public key, plus trade timeout, from message into B
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerPirateChainPublicKeyLastByteOffset));
+				// Store last byte of partner's Pirate Chain public key
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerPirateChainPublicKeyLastBytePointer));
+				// Extract AT trade timeout (minutes) (from B2)
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B2, addrRefundTimeout));
+
+				// Grab next 32 bytes
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessageHashOfSecretAOffset));
+
+				// Extract hash-of-secret-A (we only really use values from B1-B3)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrHashOfSecretAPointer));
+				// Extract lockTime-A (from B4)
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrLockTimeA));
+
+				// Calculate trade timeout refund 'timestamp' by adding addrRefundTimeout minutes to this transaction's 'timestamp', then save into addrRefundTimestamp
+				codeByteBuffer.put(OpCode.EXT_FUN_RET_DAT_2.compile(FunctionCode.ADD_MINUTES_TO_TIMESTAMP, addrRefundTimestamp, addrLastTxnTimestamp, addrRefundTimeout));
+
+				/* We are in 'trade mode' */
+				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.TRADING.value));
+
+				// Set restart position to after this opcode
+				codeByteBuffer.put(OpCode.SET_PCS.compile());
+
+				/* Loop, waiting for trade timeout or 'redeem' MESSAGE from Qortal trade partner */
+
+				// Fetch current block 'timestamp'
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_BLOCK_TIMESTAMP, addrBlockTimestamp));
+				// If we're not past refund 'timestamp' then look for next transaction
+				codeByteBuffer.put(OpCode.BLT_DAT.compile(addrBlockTimestamp, addrRefundTimestamp, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
+				// We're past refund 'timestamp' so go refund everything back to AT creator
+				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRefund == null ? 0 : labelRefund));
+
+				/* Transaction processing loop */
+				labelRedeemTxnLoop = codeByteBuffer.position();
+
+				// Find next transaction to this AT since the last one (if any)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
+				// If no transaction found, A will be zero. If A is zero, set addrComparator to 1, otherwise 0.
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.CHECK_A_IS_ZERO, addrResult));
+				// If addrResult is zero (i.e. A is non-zero, transaction was found) then go check transaction
+				codeByteBuffer.put(OpCode.BZR_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelCheckRedeemTxn)));
+				// Stop and wait for next block
+				codeByteBuffer.put(OpCode.STP_IMD.compile());
+
+				/* Check transaction */
+				labelCheckRedeemTxn = codeByteBuffer.position();
+
+				// Update our 'last found transaction's timestamp' using 'timestamp' from transaction
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TIMESTAMP_FROM_TX_IN_A, addrLastTxnTimestamp));
+				// Extract transaction type (message/payment) from transaction and save type in addrTxnType
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TYPE_FROM_TX_IN_A, addrTxnType));
+				// If transaction type is not MESSAGE type then go look for another transaction
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrTxnType, addrMessageTxnType, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
+
+				/* Check message payload length */
+				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(QortalFunctionCode.GET_MESSAGE_LENGTH_FROM_TX_IN_A.value, addrMessageLength));
+				// If message length matches, branch to sender checking code
+				codeByteBuffer.put(OpCode.BEQ_DAT.compile(addrMessageLength, addrExpectedRedeemMessageLength, calcOffset(codeByteBuffer, labelCheckRedeemTxnSender)));
+				// Message length didn't match - go back to finding another 'redeem' MESSAGE transaction
+				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRedeemTxnLoop == null ? 0 : labelRedeemTxnLoop));
+
+				/* Check transaction's sender */
+				labelCheckRedeemTxnSender = codeByteBuffer.position();
+
+				// Extract sender address from transaction into B register
+				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_ADDRESS_FROM_TX_IN_A_INTO_B));
+				// Save B register into data segment starting at addrMessageSender1 (as pointed to by addrMessageSenderPointer)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageSenderPointer));
+				// Compare each part of transaction's sender's address with expected address. If they don't match, look for another transaction.
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrQortalPartnerAddress1, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrQortalPartnerAddress2, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrQortalPartnerAddress3, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
+				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrQortalPartnerAddress4, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
+
+				/* Check 'secret-A' in transaction's message */
+
+				// Extract secret-A from first 32 bytes of message from transaction into B register
+				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_MESSAGE_FROM_TX_IN_A_INTO_B));
+				// Save B register into data segment starting at addrMessageData (as pointed to by addrMessageDataPointer)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageDataPointer));
+				// Load B register with expected hash result (as pointed to by addrHashOfSecretAPointer)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.SET_B_IND, addrHashOfSecretAPointer));
+				// Perform HASH160 using source data at addrMessageData. (Location and length specified via addrMessageDataPointer and addrMessageDataLength).
+				// Save the equality result (1 if they match, 0 otherwise) into addrResult.
+				codeByteBuffer.put(OpCode.EXT_FUN_RET_DAT_2.compile(FunctionCode.CHECK_HASH160_WITH_B, addrResult, addrMessageDataPointer, addrMessageDataLength));
+				// If hashes don't match, addrResult will be zero so go find another transaction
+				codeByteBuffer.put(OpCode.BNZ_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelPayout)));
+				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRedeemTxnLoop == null ? 0 : labelRedeemTxnLoop));
+
+				/* Success! Pay arranged amount to receiving address */
+				labelPayout = codeByteBuffer.position();
+
+				// Extract Qortal receiving address from next 32 bytes of message from transaction into B register
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrRedeemMessageReceivingAddressOffset));
+				// Save B register into data segment starting at addrPartnerReceivingAddress (as pointed to by addrPartnerReceivingAddressPointer)
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerReceivingAddressPointer));
+				// Pay AT's balance to receiving address
+				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PAY_TO_ADDRESS_IN_B, addrQortAmount));
+				// Set redeemed mode
+				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REDEEMED.value));
+				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
+				codeByteBuffer.put(OpCode.FIN_IMD.compile());
+
+				// Fall-through to refunding any remaining balance back to AT creator
+
+				/* Refund balance back to AT creator */
+				labelRefund = codeByteBuffer.position();
+
+				// Set refunded mode
+				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REFUNDED.value));
+				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
+				codeByteBuffer.put(OpCode.FIN_IMD.compile());
+			} catch (CompilationException e) {
+				throw new IllegalStateException("Unable to compile ARRR-QORT ACCT?", e);
+			}
+		}
+
+		codeByteBuffer.flip();
+
+		byte[] codeBytes = new byte[codeByteBuffer.limit()];
+		codeByteBuffer.get(codeBytes);
+
+		assert Arrays.equals(Crypto.digest(codeBytes), PirateChainACCTv3.CODE_BYTES_HASH)
+			: String.format("BTCACCT.CODE_BYTES_HASH mismatch: expected %s, actual %s", HashCode.fromBytes(CODE_BYTES_HASH), HashCode.fromBytes(Crypto.digest(codeBytes)));
+
+		final short ciyamAtVersion = 2;
+		final short numCallStackPages = 0;
+		final short numUserStackPages = 0;
+		final long minActivationAmount = 0L;
+
+		return MachineState.toCreationBytes(ciyamAtVersion, codeBytes, dataByteBuffer.array(), numCallStackPages, numUserStackPages, minActivationAmount);
+	}
+
+	/**
+	 * Returns CrossChainTradeData with useful info extracted from AT.
+	 */
+	@Override
+	public CrossChainTradeData populateTradeData(Repository repository, ATData atData) throws DataException {
+		ATStateData atStateData = repository.getATRepository().getLatestATState(atData.getATAddress());
+		return populateTradeData(repository, atData.getCreatorPublicKey(), atData.getCreation(), atStateData);
+	}
+
+	/**
+	 * Returns CrossChainTradeData with useful info extracted from AT.
+	 */
+	@Override
+	public CrossChainTradeData populateTradeData(Repository repository, ATStateData atStateData) throws DataException {
+		ATData atData = repository.getATRepository().fromATAddress(atStateData.getATAddress());
+		return populateTradeData(repository, atData.getCreatorPublicKey(), atData.getCreation(), atStateData);
+	}
+
+	/**
+	 * Returns CrossChainTradeData with useful info extracted from AT.
+	 */
+	public CrossChainTradeData populateTradeData(Repository repository, byte[] creatorPublicKey, long creationTimestamp, ATStateData atStateData) throws DataException {
+		byte[] addressBytes = new byte[25]; // for general use
+		String atAddress = atStateData.getATAddress();
+
+		CrossChainTradeData tradeData = new CrossChainTradeData();
+
+		tradeData.foreignBlockchain = SupportedBlockchain.PIRATECHAIN.name();
+		tradeData.acctName = NAME;
+
+		tradeData.qortalAtAddress = atAddress;
+		tradeData.qortalCreator = Crypto.toAddress(creatorPublicKey);
+		tradeData.creationTimestamp = creationTimestamp;
+
+		Account atAccount = new Account(repository, atAddress);
+		tradeData.qortBalance = atAccount.getConfirmedBalance(Asset.QORT);
+
+		byte[] stateData = atStateData.getStateData();
+		ByteBuffer dataByteBuffer = ByteBuffer.wrap(stateData);
+		dataByteBuffer.position(MachineState.HEADER_LENGTH);
+
+		/* Constants */
+
+		// Skip creator's trade address
+		dataByteBuffer.get(addressBytes);
+		tradeData.qortalCreatorTradeAddress = Base58.encode(addressBytes);
+		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
+
+		// Creator's PirateChain/foreign public key (full 33 bytes, not hashed, so ignore references to "PKH")
+		tradeData.creatorForeignPKH = new byte[33];
+		dataByteBuffer.get(tradeData.creatorForeignPKH);
+		dataByteBuffer.position(dataByteBuffer.position() + 40 - tradeData.creatorForeignPKH.length); // skip to 40 bytes
+
+		// We don't use secret-B
+		tradeData.hashOfSecretB = null;
+
+		// Redeem payout
+		tradeData.qortAmount = dataByteBuffer.getLong();
+
+		// Expected ARRR amount
+		tradeData.expectedForeignAmount = dataByteBuffer.getLong();
+
+		// Trade timeout
+		tradeData.tradeTimeout = (int) dataByteBuffer.getLong();
+
+		// Skip MESSAGE transaction type
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip expected 'trade' message length
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip expected 'redeem' message length
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to creator's address
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to partner's Qortal trade address
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to message sender
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip 'trade' message data offset for first 32 bytes of partner's Pirate Chain public key
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip 'trade' message data offset for last 32 byte of partner's Pirate Chain public key
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to partner's Pirate Chain public key (first 32 bytes)
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to partner's Pirate Chain public key (last byte)
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip 'trade' message data offset for hash-of-secret-A
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to hash-of-secret-A
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip 'redeem' message data offset for partner's Qortal receiving address
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to message data
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip message data length
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip pointer to partner's receiving address
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		/* End of constants / begin variables */
+
+		// Skip AT creator's address
+		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
+
+		// Partner's trade address (if present)
+		dataByteBuffer.get(addressBytes);
+		String qortalRecipient = Base58.encode(addressBytes);
+		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
+
+		// Potential lockTimeA (if in trade mode)
+		int lockTimeA = (int) dataByteBuffer.getLong();
+
+		// AT refund timeout (probably only useful for debugging)
+		int refundTimeout = (int) dataByteBuffer.getLong();
+
+		// Trade-mode refund timestamp (AT 'timestamp' converted to Qortal block height)
+		long tradeRefundTimestamp = dataByteBuffer.getLong();
+
+		// Skip last transaction timestamp
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip block timestamp
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip transaction type
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip temporary result
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip temporary message sender
+		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
+
+		// Skip message length
+		dataByteBuffer.position(dataByteBuffer.position() + 8);
+
+		// Skip temporary message data
+		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
+
+		// Potential hash160 of secret A
+		byte[] hashOfSecretA = new byte[20];
+		dataByteBuffer.get(hashOfSecretA);
+		dataByteBuffer.position(dataByteBuffer.position() + 32 - hashOfSecretA.length); // skip to 32 bytes
+
+		// Potential partner's PirateChain public key
+		byte[] partnerPirateChainPublicKey = new byte[33];
+		dataByteBuffer.get(partnerPirateChainPublicKey);
+		dataByteBuffer.position(dataByteBuffer.position() + 64 - partnerPirateChainPublicKey.length); // skip to 64 bytes
+
+		// Partner's receiving address (if present)
+		byte[] partnerReceivingAddress = new byte[25];
+		dataByteBuffer.get(partnerReceivingAddress);
+		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerReceivingAddress.length); // skip to 32 bytes
+
+		// Trade AT's 'mode'
+		long modeValue = dataByteBuffer.getLong();
+		AcctMode mode = AcctMode.valueOf((int) (modeValue & 0xffL));
+
+		/* End of variables */
+
+		if (mode != null && mode != AcctMode.OFFERING) {
+			tradeData.mode = mode;
+			tradeData.refundTimeout = refundTimeout;
+			tradeData.tradeRefundHeight = new Timestamp(tradeRefundTimestamp).blockHeight;
+			tradeData.qortalPartnerAddress = qortalRecipient;
+			tradeData.hashOfSecretA = hashOfSecretA;
+			tradeData.partnerForeignPKH = partnerPirateChainPublicKey; // Not hashed
+			tradeData.lockTimeA = lockTimeA;
+
+			if (mode == AcctMode.REDEEMED)
+				tradeData.qortalPartnerReceivingAddress = Base58.encode(partnerReceivingAddress);
+		} else {
+			tradeData.mode = AcctMode.OFFERING;
+		}
+
+		tradeData.duplicateDeprecated();
+
+		return tradeData;
+	}
+
+	/** Returns 'offer' MESSAGE payload for trade partner to send to AT creator's trade address. */
+	public static byte[] buildOfferMessage(byte[] partnerBitcoinPublicKey, byte[] hashOfSecretA, int lockTimeA) {
+		byte[] lockTimeABytes = BitTwiddling.toBEByteArray((long) lockTimeA);
+		return Bytes.concat(partnerBitcoinPublicKey, hashOfSecretA, lockTimeABytes);
+	}
+
+	/** Returns info extracted from 'offer' MESSAGE payload sent by trade partner to AT creator's trade address, or null if not valid. */
+	public static OfferMessageData extractOfferMessageData(byte[] messageData) {
+		if (messageData == null || messageData.length != OFFER_MESSAGE_LENGTH)
+			return null;
+
+		OfferMessageData offerMessageData = new OfferMessageData();
+		offerMessageData.partnerPirateChainPublicKey = Arrays.copyOfRange(messageData, 0, 33);
+		offerMessageData.hashOfSecretA = Arrays.copyOfRange(messageData, 33, 53);
+		offerMessageData.lockTimeA = BitTwiddling.longFromBEBytes(messageData, 53);
+
+		return offerMessageData;
+	}
+
+	/** Returns 'trade' MESSAGE payload for AT creator to send to AT. */
+	public static byte[] buildTradeMessage(String partnerQortalTradeAddress, byte[] partnerBitcoinPublicKey, byte[] hashOfSecretA, int lockTimeA, int refundTimeout) {
+		byte[] data = new byte[TRADE_MESSAGE_LENGTH];
+		byte[] partnerQortalAddressBytes = Base58.decode(partnerQortalTradeAddress);
+		byte[] lockTimeABytes = BitTwiddling.toBEByteArray((long) lockTimeA);
+		byte[] refundTimeoutBytes = BitTwiddling.toBEByteArray((long) refundTimeout);
+
+		System.arraycopy(partnerQortalAddressBytes, 0, data, 0, partnerQortalAddressBytes.length);
+		System.arraycopy(partnerBitcoinPublicKey, 0, data, 32, partnerBitcoinPublicKey.length);
+		System.arraycopy(refundTimeoutBytes, 0, data, 72, refundTimeoutBytes.length);
+		System.arraycopy(hashOfSecretA, 0, data, 80, hashOfSecretA.length);
+		System.arraycopy(lockTimeABytes, 0, data, 104, lockTimeABytes.length);
+
+		return data;
+	}
+
+	/** Returns 'cancel' MESSAGE payload for AT creator to cancel trade AT. */
+	@Override
+	public byte[] buildCancelMessage(String creatorQortalAddress) {
+		byte[] data = new byte[CANCEL_MESSAGE_LENGTH];
+		byte[] creatorQortalAddressBytes = Base58.decode(creatorQortalAddress);
+
+		System.arraycopy(creatorQortalAddressBytes, 0, data, 0, creatorQortalAddressBytes.length);
+
+		return data;
+	}
+
+	/** Returns 'redeem' MESSAGE payload for trade partner to send to AT. */
+	public static byte[] buildRedeemMessage(byte[] secretA, String qortalReceivingAddress) {
+		byte[] data = new byte[REDEEM_MESSAGE_LENGTH];
+		byte[] qortalReceivingAddressBytes = Base58.decode(qortalReceivingAddress);
+
+		System.arraycopy(secretA, 0, data, 0, secretA.length);
+		System.arraycopy(qortalReceivingAddressBytes, 0, data, 32, qortalReceivingAddressBytes.length);
+
+		return data;
+	}
+
+	/** Returns refund timeout (minutes) based on trade partner's 'offer' MESSAGE timestamp and P2SH-A locktime. */
+	public static int calcRefundTimeout(long offerMessageTimestamp, int lockTimeA) {
+		// refund should be triggered halfway between offerMessageTimestamp and lockTimeA
+		return (int) ((lockTimeA - (offerMessageTimestamp / 1000L)) / 2L / 60L);
+	}
+
+	@Override
+	public byte[] findSecretA(Repository repository, CrossChainTradeData crossChainTradeData) throws DataException {
+		String atAddress = crossChainTradeData.qortalAtAddress;
+		String redeemerAddress = crossChainTradeData.qortalPartnerAddress;
+
+		// We don't have partner's public key so we check every message to AT
+		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, atAddress, null, null, null);
+		if (messageTransactionsData == null)
+			return null;
+
+		// Find 'redeem' message
+		for (MessageTransactionData messageTransactionData : messageTransactionsData) {
+			// Check message payload type/encryption
+			if (messageTransactionData.isText() || messageTransactionData.isEncrypted())
+				continue;
+
+			// Check message payload size
+			byte[] messageData = messageTransactionData.getData();
+			if (messageData.length != REDEEM_MESSAGE_LENGTH)
+				// Wrong payload length
+				continue;
+
+			// Check sender
+			if (!Crypto.toAddress(messageTransactionData.getSenderPublicKey()).equals(redeemerAddress))
+				// Wrong sender;
+				continue;
+
+			// Extract secretA
+			byte[] secretA = new byte[32];
+			System.arraycopy(messageData, 0, secretA, 0, secretA.length);
+
+			byte[] hashOfSecretA = Crypto.hash160(secretA);
+			if (!Arrays.equals(hashOfSecretA, crossChainTradeData.hashOfSecretA))
+				continue;
+
+			return secretA;
+		}
+
+		return null;
+	}
+
+}

src/main/java/org/qortal/crosschain/PirateChainHTLC.java

@@ -0,0 +1,404 @@
+package org.qortal.crosschain;
+
+import com.google.common.hash.HashCode;
+import com.google.common.primitives.Bytes;
+import org.bitcoinj.core.*;
+import org.bitcoinj.script.Script;
+import org.bitcoinj.script.ScriptChunk;
+import org.qortal.crypto.Crypto;
+import org.qortal.utils.Base58;
+import org.qortal.utils.BitTwiddling;
+
+import java.util.*;
+import static org.qortal.crosschain.BitcoinyHTLC.Status;
+
+public class PirateChainHTLC {
+
+	public static final int SECRET_LENGTH = 32;
+	public static final int MIN_LOCKTIME = 1500000000;
+
+	public static final long NO_LOCKTIME_NO_RBF_SEQUENCE = 0xFFFFFFFFL;
+	public static final long LOCKTIME_NO_RBF_SEQUENCE = NO_LOCKTIME_NO_RBF_SEQUENCE - 1;
+
+	// Assuming node's trade-bot has no more than 100 entries?
+	private static final int MAX_CACHE_ENTRIES = 100;
+
+	// Max time-to-live for cache entries (milliseconds)
+	private static final long CACHE_TIMEOUT = 30_000L;
+
+	@SuppressWarnings("serial")
+	private static final Map<String, byte[]> SECRET_CACHE = new LinkedHashMap<>(MAX_CACHE_ENTRIES + 1, 0.75F, true) {
+		// This method is called just after a new entry has been added
+		@Override
+		public boolean removeEldestEntry(Map.Entry<String, byte[]> eldest) {
+			return size() > MAX_CACHE_ENTRIES;
+		}
+	};
+	private static final byte[] NO_SECRET_CACHE_ENTRY = new byte[0];
+
+	@SuppressWarnings("serial")
+	private static final Map<String, Status> STATUS_CACHE = new LinkedHashMap<>(MAX_CACHE_ENTRIES + 1, 0.75F, true) {
+		// This method is called just after a new entry has been added
+		@Override
+		public boolean removeEldestEntry(Map.Entry<String, Status> eldest) {
+			return size() > MAX_CACHE_ENTRIES;
+		}
+	};
+
+	/*
+	 * OP_RETURN + OP_PUSHDATA1 + bytes (not part of actual redeem script - used for "push only" secondary output when funding P2SH)
+	 *
+	 * OP_IF (if top stack value isn't false) (true=refund; false=redeem) (boolean is then removed from stack)
+	 * 		<push 4 bytes> <intended locktime>
+	 * 		OP_CHECKLOCKTIMEVERIFY (if stack locktime greater than transaction's lock time - i.e. refunding but too soon - then fail validation)
+	 * 		OP_DROP (remove locktime from top of stack)
+	 * 		<push 33 bytes> <intended refunder public key>
+	 * 		OP_CHECKSIG (check signature and public key are correct; returns 1 or 0)
+	 * OP_ELSE (if top stack value was false, i.e. attempting to redeem)
+	 * 		OP_SIZE (push length of top item - the secret - to the top of the stack)
+	 * 		<push 1 byte> 32
+	 * 		OP_EQUALVERIFY (unhashed secret must be 32 bytes in length)
+	 * 		OP_HASH160 (hash the secret)
+	 * 		<push 20 bytes> <intended secret hash>
+	 * 		OP_EQUALVERIFY (ensure hash of supplied secret matches intended secret hash; transaction invalid if no match)
+	 * 		<push 33 bytes> <intended redeemer public key>
+	 * 		OP_CHECKSIG (check signature and public key are correct; returns 1 or 0)
+	 * OP_ENDIF
+	 */
+
+	private static final byte[] pushOnlyPrefix = HashCode.fromString("6a4c").asBytes(); // OP_RETURN + push(redeem script)
+	private static final byte[] redeemScript1 = HashCode.fromString("6304").asBytes(); // OP_IF push(4 bytes locktime)
+	private static final byte[] redeemScript2 = HashCode.fromString("b17521").asBytes(); // OP_CHECKLOCKTIMEVERIFY OP_DROP push(33 bytes refund pubkey)
+	private static final byte[] redeemScript3 = HashCode.fromString("ac6782012088a914").asBytes(); // OP_CHECKSIG OP_ELSE OP_SIZE push(0x20) OP_EQUALVERIFY OP_HASH160 push(20 bytes hash of secret)
+	private static final byte[] redeemScript4 = HashCode.fromString("8821").asBytes(); // OP_EQUALVERIFY push(33 bytes redeem pubkey)
+	private static final byte[] redeemScript5 = HashCode.fromString("ac68").asBytes(); // OP_CHECKSIG OP_ENDIF
+
+	/**
+	 * Returns redeemScript used for cross-chain trading.
+	 * <p>
+	 * See comments in {@link PirateChainHTLC} for more details.
+	 * 
+	 * @param refunderPubKey 33-byte P2SH funder's public key, for refunding purposes
+	 * @param lockTime seconds-since-epoch threshold, after which P2SH funder can claim refund
+	 * @param redeemerPubKey 33-byte P2SH redeemer's public key
+	 * @param hashOfSecret 20-byte HASH160 of secret, used by P2SH redeemer to claim funds
+	 */
+	public static byte[] buildScript(byte[] refunderPubKey, int lockTime, byte[] redeemerPubKey, byte[] hashOfSecret) {
+		return Bytes.concat(redeemScript1, BitTwiddling.toLEByteArray((int) (lockTime & 0xffffffffL)), redeemScript2,
+				refunderPubKey, redeemScript3, hashOfSecret, redeemScript4, redeemerPubKey, redeemScript5);
+	}
+
+	/**
+	 * Alternative to buildScript() above, this time with a prefix suitable for adding the redeem script
+	 * to a "push only" output (via OP_RETURN followed by OP_PUSHDATA1)
+	 *
+	 * @param refunderPubKey 33-byte P2SH funder's public key, for refunding purposes
+	 * @param lockTime seconds-since-epoch threshold, after which P2SH funder can claim refund
+	 * @param redeemerPubKey 33-byte P2SH redeemer's public key
+	 * @param hashOfSecret 20-byte HASH160 of secret, used by P2SH redeemer to claim funds
+	 * @return
+	 */
+	public static byte[] buildScriptWithPrefix(byte[] refunderPubKey, int lockTime, byte[] redeemerPubKey, byte[] hashOfSecret) {
+		byte[] redeemScript = buildScript(refunderPubKey, lockTime, redeemerPubKey, hashOfSecret);
+		int size = redeemScript.length;
+		String sizeHex = Integer.toHexString(size & 0xFF);
+		return Bytes.concat(pushOnlyPrefix, HashCode.fromString(sizeHex).asBytes(), redeemScript);
+	}
+
+	/**
+	 * Returns 'secret', if any, given HTLC's P2SH address.
+	 * <p>
+	 * @throws ForeignBlockchainException
+	 */
+	public static byte[] findHtlcSecret(Bitcoiny bitcoiny, String p2shAddress) throws ForeignBlockchainException {
+		NetworkParameters params = bitcoiny.getNetworkParameters();
+		String compoundKey = String.format("%s-%s-%d", params.getId(), p2shAddress, System.currentTimeMillis() / CACHE_TIMEOUT);
+
+		byte[] secret = SECRET_CACHE.getOrDefault(compoundKey, NO_SECRET_CACHE_ENTRY);
+		if (secret != NO_SECRET_CACHE_ENTRY)
+			return secret;
+
+		List<byte[]> rawTransactions = bitcoiny.getAddressTransactions(p2shAddress);
+
+		for (byte[] rawTransaction : rawTransactions) {
+			Transaction transaction = new Transaction(params, rawTransaction);
+
+			// Cycle through inputs, looking for one that spends our HTLC
+			for (TransactionInput input : transaction.getInputs()) {
+				Script scriptSig = input.getScriptSig();
+				List<ScriptChunk> scriptChunks = scriptSig.getChunks();
+
+				// Expected number of script chunks for redeem. Refund might not have the same number.
+				int expectedChunkCount = 1 /*secret*/ + 1 /*sig*/ + 1 /*pubkey*/ + 1 /*redeemScript*/;
+				if (scriptChunks.size() != expectedChunkCount)
+					continue;
+
+				// We're expecting last chunk to contain the actual redeemScript
+				ScriptChunk lastChunk = scriptChunks.get(scriptChunks.size() - 1);
+				byte[] redeemScriptBytes = lastChunk.data;
+
+				// If non-push scripts, redeemScript will be null
+				if (redeemScriptBytes == null)
+					continue;
+
+				byte[] redeemScriptHash = Crypto.hash160(redeemScriptBytes);
+				Address inputAddress = LegacyAddress.fromScriptHash(params, redeemScriptHash);
+
+				if (!inputAddress.toString().equals(p2shAddress))
+					// Input isn't spending our HTLC
+					continue;
+
+				secret = scriptChunks.get(0).data;
+				if (secret.length != PirateChainHTLC.SECRET_LENGTH)
+					continue;
+
+				// Cache secret for a while
+				SECRET_CACHE.put(compoundKey, secret);
+
+				return secret;
+			}
+		}
+
+		// Cache negative result
+		SECRET_CACHE.put(compoundKey, null);
+
+		return null;
+	}
+
+	/**
+	 * Returns a string containing the txid of the transaction that funded supplied <tt>p2shAddress</tt>
+	 * We have to do this in a bit of a roundabout way due to the Pirate Light Client server omitting
+	 * transaction hashes from the raw transaction data.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	public static String getFundingTxid(BitcoinyBlockchainProvider blockchain, String p2shAddress) throws ForeignBlockchainException {
+		byte[] ourScriptPubKey = addressToScriptPubKey(p2shAddress);
+		// HASH160(redeem script) for this p2shAddress
+		byte[] ourRedeemScriptHash = addressToRedeemScriptHash(p2shAddress);
+
+
+		// Firstly look for an unspent output
+
+		// Note: we can't include unconfirmed transactions here because the Pirate light wallet server requires a block range
+		List<UnspentOutput> unspentOutputs = blockchain.getUnspentOutputs(p2shAddress, false);
+		for (UnspentOutput unspentOutput : unspentOutputs) {
+
+			if (!Arrays.equals(ourScriptPubKey, unspentOutput.script)) {
+				continue;
+			}
+
+			return HashCode.fromBytes(unspentOutput.hash).toString();
+		}
+
+
+		// No valid unspent outputs, so must be already spent...
+
+		// Note: we can't include unconfirmed transactions here because the Pirate light wallet server requires a block range
+		List<BitcoinyTransaction> transactions = blockchain.getAddressBitcoinyTransactions(p2shAddress, BitcoinyBlockchainProvider.EXCLUDE_UNCONFIRMED);
+
+		// Sort by confirmed first, followed by ascending height
+		transactions.sort(BitcoinyTransaction.CONFIRMED_FIRST.thenComparing(BitcoinyTransaction::getHeight));
+
+		for (BitcoinyTransaction bitcoinyTransaction : transactions) {
+
+			// Acceptable funding is one transaction output, so we're expecting only one input
+			if (bitcoinyTransaction.inputs.size() != 1)
+				// Wrong number of inputs
+				continue;
+
+			String scriptSig = bitcoinyTransaction.inputs.get(0).scriptSig;
+
+			List<byte[]> scriptSigChunks = extractScriptSigChunks(HashCode.fromString(scriptSig).asBytes());
+			if (scriptSigChunks.size() < 3 || scriptSigChunks.size() > 4)
+				// Not valid chunks for our form of HTLC
+				continue;
+
+			// Last chunk is redeem script
+			byte[] redeemScriptBytes = scriptSigChunks.get(scriptSigChunks.size() - 1);
+			byte[] redeemScriptHash = Crypto.hash160(redeemScriptBytes);
+			if (!Arrays.equals(redeemScriptHash, ourRedeemScriptHash))
+				// Not spending our specific HTLC redeem script
+				continue;
+
+			return bitcoinyTransaction.inputs.get(0).outputTxHash;
+
+		}
+
+		return null;
+	}
+
+	/**
+	 * Returns a string containing the unspent txid of the transaction that funded supplied <tt>p2shAddress</tt>
+	 * and is at least the value specified in <tt>minimumAmount</tt>
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	public static String getUnspentFundingTxid(BitcoinyBlockchainProvider blockchain, String p2shAddress, long minimumAmount) throws ForeignBlockchainException {
+		byte[] ourScriptPubKey = addressToScriptPubKey(p2shAddress);
+
+		// Note: we can't include unconfirmed transactions here because the Pirate light wallet server requires a block range
+		List<UnspentOutput> unspentOutputs = blockchain.getUnspentOutputs(p2shAddress, false);
+		for (UnspentOutput unspentOutput : unspentOutputs) {
+
+			if (!Arrays.equals(ourScriptPubKey, unspentOutput.script)) {
+				// Not funding our specific HTLC script hash
+				continue;
+			}
+
+			if (unspentOutput.value < minimumAmount) {
+				// Not funding the required amount
+				continue;
+			}
+
+			return HashCode.fromBytes(unspentOutput.hash).toString();
+		}
+
+
+		// No valid unspent outputs, so must be already spent
+		return null;
+	}
+
+	/**
+	 * Returns HTLC status, given P2SH address and expected redeem/refund amount
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	public static Status determineHtlcStatus(BitcoinyBlockchainProvider blockchain, String p2shAddress, long minimumAmount) throws ForeignBlockchainException {
+		String compoundKey = String.format("%s-%s-%d", blockchain.getNetId(), p2shAddress, System.currentTimeMillis() / CACHE_TIMEOUT);
+
+		Status cachedStatus = STATUS_CACHE.getOrDefault(compoundKey, null);
+		if (cachedStatus != null)
+			return cachedStatus;
+
+		byte[] ourScriptPubKey = addressToScriptPubKey(p2shAddress);
+
+		// Note: we can't include unconfirmed transactions here because the Pirate light wallet server requires a block range
+		List<BitcoinyTransaction> transactions = blockchain.getAddressBitcoinyTransactions(p2shAddress, BitcoinyBlockchainProvider.EXCLUDE_UNCONFIRMED);
+
+		// Sort by confirmed first, followed by ascending height
+		transactions.sort(BitcoinyTransaction.CONFIRMED_FIRST.thenComparing(BitcoinyTransaction::getHeight));
+
+		// Transaction cache
+		//Map<String, BitcoinyTransaction> transactionsByHash = new HashMap<>();
+		// HASH160(redeem script) for this p2shAddress
+		byte[] ourRedeemScriptHash = addressToRedeemScriptHash(p2shAddress);
+
+		// Check for spends first, caching full transaction info as we progress just in case we don't return in this loop
+		for (BitcoinyTransaction bitcoinyTransaction : transactions) {
+
+			// Cache for possible later reuse
+			// transactionsByHash.put(transactionInfo.txHash, bitcoinyTransaction);
+
+			// Acceptable funding is one transaction output, so we're expecting only one input
+			if (bitcoinyTransaction.inputs.size() != 1)
+				// Wrong number of inputs
+				continue;
+
+			String scriptSig = bitcoinyTransaction.inputs.get(0).scriptSig;
+
+			List<byte[]> scriptSigChunks = extractScriptSigChunks(HashCode.fromString(scriptSig).asBytes());
+			if (scriptSigChunks.size() < 3 || scriptSigChunks.size() > 4)
+				// Not valid chunks for our form of HTLC
+				continue;
+
+			// Last chunk is redeem script
+			byte[] redeemScriptBytes = scriptSigChunks.get(scriptSigChunks.size() - 1);
+			byte[] redeemScriptHash = Crypto.hash160(redeemScriptBytes);
+			if (!Arrays.equals(redeemScriptHash, ourRedeemScriptHash))
+				// Not spending our specific HTLC redeem script
+				continue;
+
+			if (scriptSigChunks.size() == 4)
+				// If we have 4 chunks, then secret is present, hence redeem
+				cachedStatus = bitcoinyTransaction.height == 0 ? Status.REDEEM_IN_PROGRESS : Status.REDEEMED;
+			else
+				cachedStatus = bitcoinyTransaction.height == 0 ? Status.REFUND_IN_PROGRESS : Status.REFUNDED;
+
+			STATUS_CACHE.put(compoundKey, cachedStatus);
+			return cachedStatus;
+		}
+
+		String ourScriptPubKeyHex = HashCode.fromBytes(ourScriptPubKey).toString();
+
+		// Check for funding
+		for (BitcoinyTransaction bitcoinyTransaction : transactions) {
+			if (bitcoinyTransaction == null)
+				// Should be present in map!
+				throw new ForeignBlockchainException("Cached Bitcoin transaction now missing?");
+
+			// Check outputs for our specific P2SH
+			for (BitcoinyTransaction.Output output : bitcoinyTransaction.outputs) {
+				// Check amount
+				if (output.value < minimumAmount)
+					// Output amount too small (not taking fees into account)
+					continue;
+
+				String scriptPubKeyHex = output.scriptPubKey;
+				if (!scriptPubKeyHex.equals(ourScriptPubKeyHex))
+					// Not funding our specific P2SH
+					continue;
+
+				cachedStatus = bitcoinyTransaction.height == 0 ? Status.FUNDING_IN_PROGRESS : Status.FUNDED;
+				STATUS_CACHE.put(compoundKey, cachedStatus);
+				return cachedStatus;
+			}
+		}
+
+		cachedStatus = Status.UNFUNDED;
+		STATUS_CACHE.put(compoundKey, cachedStatus);
+		return cachedStatus;
+	}
+
+	private static List<byte[]> extractScriptSigChunks(byte[] scriptSigBytes) {
+		List<byte[]> chunks = new ArrayList<>();
+
+		int offset = 0;
+		int previousOffset = 0;
+		while (offset < scriptSigBytes.length) {
+			byte pushOp = scriptSigBytes[offset++];
+
+			if (pushOp < 0 || pushOp > 0x4c)
+				// Unacceptable OP
+				return Collections.emptyList();
+
+			// Special treatment for OP_PUSHDATA1
+			if (pushOp == 0x4c) {
+				if (offset >= scriptSigBytes.length)
+					// Run out of scriptSig bytes?
+					return Collections.emptyList();
+
+				pushOp = scriptSigBytes[offset++];
+			}
+
+			previousOffset = offset;
+			offset += Byte.toUnsignedInt(pushOp);
+
+			byte[] chunk = Arrays.copyOfRange(scriptSigBytes, previousOffset, offset);
+			chunks.add(chunk);
+		}
+
+		return chunks;
+	}
+
+	private static byte[] addressToScriptPubKey(String p2shAddress) {
+		// We want the HASH160 part of the P2SH address
+		byte[] p2shAddressBytes = Base58.decode(p2shAddress);
+
+		byte[] scriptPubKey = new byte[1 + 1 + 20 + 1];
+		scriptPubKey[0x00] = (byte) 0xa9; /* OP_HASH160 */
+		scriptPubKey[0x01] = (byte) 0x14; /* PUSH 0x14 bytes */
+		System.arraycopy(p2shAddressBytes, 1, scriptPubKey, 2, 0x14);
+		scriptPubKey[0x16] = (byte) 0x87; /* OP_EQUAL */
+
+		return scriptPubKey;
+	}
+
+	private static byte[] addressToRedeemScriptHash(String p2shAddress) {
+		// We want the HASH160 part of the P2SH address
+		byte[] p2shAddressBytes = Base58.decode(p2shAddress);
+
+		return Arrays.copyOfRange(p2shAddressBytes, 1, 1 + 20);
+	}
+
+}

src/main/java/org/qortal/crosschain/PirateLightClient.java

@@ -0,0 +1,649 @@
+package org.qortal.crosschain;
+
+import cash.z.wallet.sdk.rpc.CompactFormats.*;
+import cash.z.wallet.sdk.rpc.CompactTxStreamerGrpc;
+import cash.z.wallet.sdk.rpc.Service;
+import cash.z.wallet.sdk.rpc.Service.*;
+import com.google.common.hash.HashCode;
+import com.google.protobuf.ByteString;
+import io.grpc.ManagedChannel;
+import io.grpc.ManagedChannelBuilder;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.json.simple.JSONArray;
+import org.json.simple.JSONObject;
+import org.json.simple.parser.JSONParser;
+import org.json.simple.parser.ParseException;
+import org.qortal.settings.Settings;
+import org.qortal.transform.TransformationException;
+
+import java.math.BigDecimal;
+import java.util.*;
+import java.util.concurrent.TimeUnit;
+
+/** Pirate Chain network support for querying Bitcoiny-related info like block headers, transaction outputs, etc. */
+public class PirateLightClient extends BitcoinyBlockchainProvider {
+
+	private static final Logger LOGGER = LogManager.getLogger(PirateLightClient.class);
+	private static final Random RANDOM = new Random();
+
+	private static final int RESPONSE_TIME_READINGS = 5;
+	private static final long MAX_AVG_RESPONSE_TIME = 500L; // ms
+
+	public static class Server {
+		String hostname;
+
+		public enum ConnectionType { TCP, SSL }
+		ConnectionType connectionType;
+
+		int port;
+		private List<Long> responseTimes = new ArrayList<>();
+
+		public Server(String hostname, ConnectionType connectionType, int port) {
+			this.hostname = hostname;
+			this.connectionType = connectionType;
+			this.port = port;
+		}
+
+		public void addResponseTime(long responseTime) {
+			while (this.responseTimes.size() > RESPONSE_TIME_READINGS) {
+				this.responseTimes.remove(0);
+			}
+			this.responseTimes.add(responseTime);
+		}
+
+		public long averageResponseTime() {
+			if (this.responseTimes.size() < RESPONSE_TIME_READINGS) {
+				// Not enough readings yet
+				return 0L;
+			}
+			OptionalDouble average = this.responseTimes.stream().mapToDouble(a -> a).average();
+			if (average.isPresent()) {
+				return Double.valueOf(average.getAsDouble()).longValue();
+			}
+			return 0L;
+		}
+
+		@Override
+		public boolean equals(Object other) {
+			if (other == this)
+				return true;
+
+			if (!(other instanceof Server))
+				return false;
+
+			Server otherServer = (Server) other;
+
+			return this.connectionType == otherServer.connectionType
+					&& this.port == otherServer.port
+					&& this.hostname.equals(otherServer.hostname);
+		}
+
+		@Override
+		public int hashCode() {
+			return this.hostname.hashCode() ^ this.port;
+		}
+
+		@Override
+		public String toString() {
+			return String.format("%s:%s:%d", this.connectionType.name(), this.hostname, this.port);
+		}
+	}
+	private Set<Server> servers = new HashSet<>();
+	private List<Server> remainingServers = new ArrayList<>();
+	private Set<Server> uselessServers = Collections.synchronizedSet(new HashSet<>());
+
+	private final String netId;
+	private final String expectedGenesisHash;
+	private final Map<Server.ConnectionType, Integer> defaultPorts = new EnumMap<>(Server.ConnectionType.class);
+	private Bitcoiny blockchain;
+
+	private final Object serverLock = new Object();
+	private Server currentServer;
+	private ManagedChannel channel;
+	private int nextId = 1;
+
+	private static final int TX_CACHE_SIZE = 1000;
+	@SuppressWarnings("serial")
+	private final Map<String, BitcoinyTransaction> transactionCache = Collections.synchronizedMap(new LinkedHashMap<>(TX_CACHE_SIZE + 1, 0.75F, true) {
+		// This method is called just after a new entry has been added
+		@Override
+		public boolean removeEldestEntry(Map.Entry<String, BitcoinyTransaction> eldest) {
+			return size() > TX_CACHE_SIZE;
+		}
+	});
+
+	// Constructors
+
+	public PirateLightClient(String netId, String genesisHash, Collection<Server> initialServerList, Map<Server.ConnectionType, Integer> defaultPorts) {
+		this.netId = netId;
+		this.expectedGenesisHash = genesisHash;
+		this.servers.addAll(initialServerList);
+		this.defaultPorts.putAll(defaultPorts);
+	}
+
+	// Methods for use by other classes
+
+	@Override
+	public void setBlockchain(Bitcoiny blockchain) {
+		this.blockchain = blockchain;
+	}
+
+	@Override
+	public String getNetId() {
+		return this.netId;
+	}
+
+	/**
+	 * Returns current blockchain height.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public int getCurrentHeight() throws ForeignBlockchainException {
+		BlockID latestBlock = this.getCompactTxStreamerStub().getLatestBlock(null);
+
+		if (!(latestBlock instanceof BlockID))
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getLatestBlock gRPC");
+
+		return (int)latestBlock.getHeight();
+	}
+
+	/**
+	 * Returns list of compact blocks, starting from <tt>startHeight</tt> inclusive.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 * @return
+	 */
+	@Override
+	public List<CompactBlock> getCompactBlocks(int startHeight, int count) throws ForeignBlockchainException {
+		BlockID startBlock = BlockID.newBuilder().setHeight(startHeight).build();
+		BlockID endBlock = BlockID.newBuilder().setHeight(startHeight + count - 1).build();
+		BlockRange range = BlockRange.newBuilder().setStart(startBlock).setEnd(endBlock).build();
+
+		Iterator<CompactBlock> blocksIterator = this.getCompactTxStreamerStub().getBlockRange(range);
+
+		// Map from Iterator to List
+		List<CompactBlock> blocks = new ArrayList<>();
+		blocksIterator.forEachRemaining(blocks::add);
+
+		return blocks;
+	}
+
+	/**
+	 * Returns list of raw block headers, starting from <tt>startHeight</tt> inclusive.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public List<byte[]> getRawBlockHeaders(int startHeight, int count) throws ForeignBlockchainException {
+		BlockID startBlock = BlockID.newBuilder().setHeight(startHeight).build();
+		BlockID endBlock = BlockID.newBuilder().setHeight(startHeight + count - 1).build();
+		BlockRange range = BlockRange.newBuilder().setStart(startBlock).setEnd(endBlock).build();
+
+		Iterator<CompactBlock> blocks = this.getCompactTxStreamerStub().getBlockRange(range);
+
+		List<byte[]> rawBlockHeaders = new ArrayList<>();
+
+		while (blocks.hasNext()) {
+			CompactBlock block = blocks.next();
+
+			if (block.getHeader() == null) {
+				throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getBlockRange gRPC");
+			}
+
+			rawBlockHeaders.add(block.getHeader().toByteArray());
+		}
+
+		return rawBlockHeaders;
+	}
+
+	/**
+	 * Returns list of raw block timestamps, starting from <tt>startHeight</tt> inclusive.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public List<Long> getBlockTimestamps(int startHeight, int count) throws ForeignBlockchainException {
+		BlockID startBlock = BlockID.newBuilder().setHeight(startHeight).build();
+		BlockID endBlock = BlockID.newBuilder().setHeight(startHeight + count - 1).build();
+		BlockRange range = BlockRange.newBuilder().setStart(startBlock).setEnd(endBlock).build();
+
+		Iterator<CompactBlock> blocks = this.getCompactTxStreamerStub().getBlockRange(range);
+
+		List<Long> rawBlockTimestamps = new ArrayList<>();
+
+		while (blocks.hasNext()) {
+			CompactBlock block = blocks.next();
+
+			if (block.getTime() <= 0) {
+				throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getBlockRange gRPC");
+			}
+
+			rawBlockTimestamps.add(Long.valueOf(block.getTime()));
+		}
+
+		return rawBlockTimestamps;
+	}
+
+	/**
+	 * Returns confirmed balance, based on passed payment script.
+	 * <p>
+	 * @return confirmed balance, or zero if script unknown
+	 * @throws ForeignBlockchainException if there was an error
+	 */
+	@Override
+	public long getConfirmedBalance(byte[] script) throws ForeignBlockchainException {
+		throw new ForeignBlockchainException("getConfirmedBalance not yet implemented for Pirate Chain");
+	}
+
+	/**
+	 * Returns confirmed balance, based on passed base58 encoded address.
+	 * <p>
+	 * @return confirmed balance, or zero if address unknown
+	 * @throws ForeignBlockchainException if there was an error
+	 */
+	@Override
+	public long getConfirmedAddressBalance(String base58Address) throws ForeignBlockchainException {
+		AddressList addressList = AddressList.newBuilder().addAddresses(base58Address).build();
+		Balance balance = this.getCompactTxStreamerStub().getTaddressBalance(addressList);
+
+		if (!(balance instanceof Balance))
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getConfirmedAddressBalance gRPC");
+
+		return balance.getValueZat();
+	}
+
+	/**
+	 * Returns list of unspent outputs pertaining to passed address.
+	 * <p>
+	 * @return list of unspent outputs, or empty list if address unknown
+	 * @throws ForeignBlockchainException if there was an error.
+	 */
+	@Override
+	public List<UnspentOutput> getUnspentOutputs(String address, boolean includeUnconfirmed) throws ForeignBlockchainException {
+		GetAddressUtxosArg getAddressUtxosArg = GetAddressUtxosArg.newBuilder().addAddresses(address).build();
+		GetAddressUtxosReplyList replyList = this.getCompactTxStreamerStub().getAddressUtxos(getAddressUtxosArg);
+
+		if (!(replyList instanceof GetAddressUtxosReplyList))
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getUnspentOutputs gRPC");
+
+		List<GetAddressUtxosReply> unspentList = replyList.getAddressUtxosList();
+		if (unspentList == null)
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getUnspentOutputs gRPC");
+
+		List<UnspentOutput> unspentOutputs = new ArrayList<>();
+		for (GetAddressUtxosReply unspent : unspentList) {
+
+			int height = (int)unspent.getHeight();
+			// We only want unspent outputs from confirmed transactions (and definitely not mempool duplicates with height 0)
+			if (!includeUnconfirmed && height <= 0)
+				continue;
+
+			byte[] txHash = unspent.getTxid().toByteArray();
+			int outputIndex = unspent.getIndex();
+			long value = unspent.getValueZat();
+			byte[] script = unspent.getScript().toByteArray();
+			String addressRes = unspent.getAddress();
+
+			unspentOutputs.add(new UnspentOutput(txHash, outputIndex, height, value, script, addressRes));
+		}
+
+		return unspentOutputs;
+	}
+
+	/**
+	 * Returns list of unspent outputs pertaining to passed payment script.
+	 * <p>
+	 * @return list of unspent outputs, or empty list if script unknown
+	 * @throws ForeignBlockchainException if there was an error.
+	 */
+	@Override
+	public List<UnspentOutput> getUnspentOutputs(byte[] script, boolean includeUnconfirmed) throws ForeignBlockchainException {
+		String address = this.blockchain.deriveP2shAddress(script);
+		return this.getUnspentOutputs(address, includeUnconfirmed);
+	}
+
+	/**
+	 * Returns raw transaction for passed transaction hash.
+	 * <p>
+	 * NOTE: Do not mutate returned byte[]!
+	 *
+	 * @throws ForeignBlockchainException.NotFoundException if transaction not found
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public byte[] getRawTransaction(String txHash) throws ForeignBlockchainException {
+		return getRawTransaction(HashCode.fromString(txHash).asBytes());
+	}
+
+	/**
+	 * Returns raw transaction for passed transaction hash.
+	 * <p>
+	 * NOTE: Do not mutate returned byte[]!
+	 *
+	 * @throws ForeignBlockchainException.NotFoundException if transaction not found
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public byte[] getRawTransaction(byte[] txHash) throws ForeignBlockchainException {
+		ByteString byteString = ByteString.copyFrom(txHash);
+		TxFilter txFilter = TxFilter.newBuilder().setHash(byteString).build();
+		RawTransaction rawTransaction = this.getCompactTxStreamerStub().getTransaction(txFilter);
+
+		if (!(rawTransaction instanceof RawTransaction))
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getTransaction gRPC");
+
+		return rawTransaction.getData().toByteArray();
+	}
+
+	/**
+	 * Returns transaction info for passed transaction hash.
+	 * <p>
+	 * @throws ForeignBlockchainException.NotFoundException if transaction not found
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public BitcoinyTransaction getTransaction(String txHash) throws ForeignBlockchainException {
+		// Check cache first
+		BitcoinyTransaction transaction = transactionCache.get(txHash);
+		if (transaction != null)
+			return transaction;
+
+		ByteString byteString = ByteString.copyFrom(HashCode.fromString(txHash).asBytes());
+		TxFilter txFilter = TxFilter.newBuilder().setHash(byteString).build();
+		RawTransaction rawTransaction = this.getCompactTxStreamerStub().getTransaction(txFilter);
+
+		if (!(rawTransaction instanceof RawTransaction))
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain getTransaction gRPC");
+
+		byte[] transactionData = rawTransaction.getData().toByteArray();
+		String transactionDataString = HashCode.fromBytes(transactionData).toString();
+
+		JSONParser parser = new JSONParser();
+		JSONObject transactionJson;
+		try {
+			transactionJson = (JSONObject) parser.parse(transactionDataString);
+		} catch (ParseException e) {
+			throw new ForeignBlockchainException.NetworkException("Expected JSON string from Pirate Chain getTransaction gRPC");
+		}
+
+		Object inputsObj = transactionJson.get("vin");
+		if (!(inputsObj instanceof JSONArray))
+			throw new ForeignBlockchainException.NetworkException("Expected JSONArray for 'vin' from Pirate Chain getTransaction gRPC");
+
+		Object outputsObj = transactionJson.get("vout");
+		if (!(outputsObj instanceof JSONArray))
+			throw new ForeignBlockchainException.NetworkException("Expected JSONArray for 'vout' from Pirate Chain getTransaction gRPC");
+
+		try {
+			int size = ((Long) transactionJson.get("size")).intValue();
+			int locktime = ((Long) transactionJson.get("locktime")).intValue();
+
+			// Timestamp might not be present, e.g. for unconfirmed transaction
+			Object timeObj = transactionJson.get("time");
+			Integer timestamp = timeObj != null
+					? ((Long) timeObj).intValue()
+					: null;
+
+			List<BitcoinyTransaction.Input> inputs = new ArrayList<>();
+			for (Object inputObj : (JSONArray) inputsObj) {
+				JSONObject inputJson = (JSONObject) inputObj;
+
+				String scriptSig = (String) ((JSONObject) inputJson.get("scriptSig")).get("hex");
+				int sequence = ((Long) inputJson.get("sequence")).intValue();
+				String outputTxHash = (String) inputJson.get("txid");
+				int outputVout = ((Long) inputJson.get("vout")).intValue();
+
+				inputs.add(new BitcoinyTransaction.Input(scriptSig, sequence, outputTxHash, outputVout));
+			}
+
+			List<BitcoinyTransaction.Output> outputs = new ArrayList<>();
+			for (Object outputObj : (JSONArray) outputsObj) {
+				JSONObject outputJson = (JSONObject) outputObj;
+
+				String scriptPubKey = (String) ((JSONObject) outputJson.get("scriptPubKey")).get("hex");
+				long value = BigDecimal.valueOf((Double) outputJson.get("value")).setScale(8).unscaledValue().longValue();
+
+				// address too, if present in the "addresses" array
+				List<String> addresses = null;
+				Object addressesObj = ((JSONObject) outputJson.get("scriptPubKey")).get("addresses");
+				if (addressesObj instanceof JSONArray) {
+					addresses = new ArrayList<>();
+					for (Object addressObj : (JSONArray) addressesObj) {
+						addresses.add((String) addressObj);
+					}
+				}
+
+				// some peers return a single "address" string
+				Object addressObj = ((JSONObject) outputJson.get("scriptPubKey")).get("address");
+				if (addressObj instanceof String) {
+					if (addresses == null) {
+						addresses = new ArrayList<>();
+					}
+					addresses.add((String) addressObj);
+				}
+
+				// For the purposes of Qortal we require all outputs to contain addresses
+				// Some servers omit this info, causing problems down the line with balance calculations
+				// Update: it turns out that they were just using a different key - "address" instead of "addresses"
+				// The code below can remain in place, just in case a peer returns a missing address in the future
+				if (addresses == null || addresses.isEmpty()) {
+					if (this.currentServer != null) {
+						this.uselessServers.add(this.currentServer);
+						this.closeServer(this.currentServer);
+					}
+					LOGGER.info("No output addresses returned for transaction {}", txHash);
+					throw new ForeignBlockchainException(String.format("No output addresses returned for transaction %s", txHash));
+				}
+
+				outputs.add(new BitcoinyTransaction.Output(scriptPubKey, value, addresses));
+			}
+
+			transaction = new BitcoinyTransaction(txHash, size, locktime, timestamp, inputs, outputs);
+
+			// Save into cache
+			transactionCache.put(txHash, transaction);
+
+			return transaction;
+		} catch (NullPointerException | ClassCastException e) {
+			// Unexpected / invalid response from ElectrumX server
+		}
+
+		throw new ForeignBlockchainException.NetworkException("Unexpected JSON format from Pirate Chain getTransaction gRPC");
+	}
+
+	/**
+	 * Returns list of transactions, relating to passed payment script.
+	 * <p>
+	 * @return list of related transactions, or empty list if script unknown
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public List<TransactionHash> getAddressTransactions(byte[] script, boolean includeUnconfirmed) throws ForeignBlockchainException {
+		// FUTURE: implement this if needed. Probably not very useful for private blockchains.
+		throw new ForeignBlockchainException("getAddressTransactions not yet implemented for Pirate Chain");
+	}
+
+	@Override
+	public List<BitcoinyTransaction> getAddressBitcoinyTransactions(String address, boolean includeUnconfirmed) throws ForeignBlockchainException {
+		try {
+			// Firstly we need to get the latest block
+			int defaultBirthday = Settings.getInstance().getArrrDefaultBirthday();
+			BlockID endBlock = this.getCompactTxStreamerStub().getLatestBlock(null);
+			BlockID startBlock = BlockID.newBuilder().setHeight(defaultBirthday).build();
+			BlockRange blockRange = BlockRange.newBuilder().setStart(startBlock).setEnd(endBlock).build();
+
+			TransparentAddressBlockFilter blockFilter = TransparentAddressBlockFilter.newBuilder()
+					.setAddress(address)
+					.setRange(blockRange)
+					.build();
+			Iterator<Service.RawTransaction> transactionIterator = this.getCompactTxStreamerStub().getTaddressTxids(blockFilter);
+
+			// Map from Iterator to List
+			List<RawTransaction> rawTransactions = new ArrayList<>();
+			transactionIterator.forEachRemaining(rawTransactions::add);
+
+			List<BitcoinyTransaction> transactions = new ArrayList<>();
+
+			for (RawTransaction rawTransaction : rawTransactions) {
+
+				Long height = rawTransaction.getHeight();
+				if (!includeUnconfirmed && (height == null || height == 0))
+					// We only want confirmed transactions
+					continue;
+
+				byte[] transactionData = rawTransaction.getData().toByteArray();
+				String transactionDataHex = HashCode.fromBytes(transactionData).toString();
+				BitcoinyTransaction bitcoinyTransaction = PirateChain.deserializeRawTransaction(transactionDataHex);
+				bitcoinyTransaction.height = height.intValue();
+				transactions.add(bitcoinyTransaction);
+			}
+
+			return transactions;
+		}
+		catch (RuntimeException | TransformationException e) {
+			throw new ForeignBlockchainException(String.format("Unable to get transactions for address %s: %s", address, e.getMessage()));
+		}
+	}
+
+	/**
+	 * Broadcasts raw transaction to network.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	@Override
+	public void broadcastTransaction(byte[] transactionBytes) throws ForeignBlockchainException {
+		ByteString byteString = ByteString.copyFrom(transactionBytes);
+		RawTransaction rawTransaction = RawTransaction.newBuilder().setData(byteString).build();
+		SendResponse sendResponse = this.getCompactTxStreamerStub().sendTransaction(rawTransaction);
+
+		if (!(sendResponse instanceof SendResponse))
+			throw new ForeignBlockchainException.NetworkException("Unexpected output from Pirate Chain broadcastTransaction gRPC");
+
+		if (sendResponse.getErrorCode() != 0)
+			throw new ForeignBlockchainException.NetworkException(String.format("Unexpected error code from Pirate Chain broadcastTransaction gRPC: %d", sendResponse.getErrorCode()));
+	}
+
+	// Class-private utility methods
+
+
+	/**
+	 * Performs RPC call, with automatic reconnection to different server if needed.
+	 * <p>
+	 * @return "result" object from within JSON output
+	 * @throws ForeignBlockchainException if server returns error or something goes wrong
+	 */
+	private CompactTxStreamerGrpc.CompactTxStreamerBlockingStub getCompactTxStreamerStub() throws ForeignBlockchainException {
+		synchronized (this.serverLock) {
+			if (this.remainingServers.isEmpty())
+				this.remainingServers.addAll(this.servers);
+
+			while (haveConnection()) {
+				// If we have more servers and the last one replied slowly, try another
+				if (!this.remainingServers.isEmpty()) {
+					long averageResponseTime = this.currentServer.averageResponseTime();
+					if (averageResponseTime > MAX_AVG_RESPONSE_TIME) {
+						LOGGER.info("Slow average response time {}ms from {} - trying another server...", averageResponseTime, this.currentServer.hostname);
+						this.closeServer();
+						continue;
+					}
+				}
+
+				return CompactTxStreamerGrpc.newBlockingStub(this.channel);
+
+//				// Didn't work, try another server...
+//				this.closeServer();
+			}
+
+			// Failed to perform RPC - maybe lack of servers?
+			LOGGER.info("Error: No connected Pirate Light servers when trying to make RPC call");
+			throw new ForeignBlockchainException.NetworkException("No connected Pirate Light servers when trying to make RPC call");
+		}
+	}
+
+	/** Returns true if we have, or create, a connection to an ElectrumX server. */
+	private boolean haveConnection() throws ForeignBlockchainException {
+		if (this.currentServer != null && this.channel != null && !this.channel.isShutdown())
+			return true;
+
+		while (!this.remainingServers.isEmpty()) {
+			Server server = this.remainingServers.remove(RANDOM.nextInt(this.remainingServers.size()));
+			LOGGER.trace(() -> String.format("Connecting to %s", server));
+
+			try {
+				this.channel = ManagedChannelBuilder.forAddress(server.hostname, server.port).build();
+
+				CompactTxStreamerGrpc.CompactTxStreamerBlockingStub stub = CompactTxStreamerGrpc.newBlockingStub(this.channel);
+				LightdInfo lightdInfo = stub.getLightdInfo(Empty.newBuilder().build());
+
+				if (lightdInfo == null || lightdInfo.getBlockHeight() <= 0)
+					continue;
+
+				// TODO: find a way to verify that the server is using the expected chain
+
+//				if (featuresJson == null || Double.valueOf((String) featuresJson.get("protocol_min")) < MIN_PROTOCOL_VERSION)
+//					continue;
+
+//				if (this.expectedGenesisHash != null && !((String) featuresJson.get("genesis_hash")).equals(this.expectedGenesisHash))
+//					continue;
+
+				LOGGER.debug(() -> String.format("Connected to %s", server));
+				this.currentServer = server;
+				return true;
+			} catch (Exception e) {
+				// Didn't work, try another server...
+				closeServer();
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Closes connection to <tt>server</tt> if it is currently connected server.
+	 * @param server
+	 */
+	private void closeServer(Server server) {
+		synchronized (this.serverLock) {
+			if (this.currentServer == null || !this.currentServer.equals(server) || this.channel == null) {
+				return;
+			}
+
+			// Close the gRPC managed-channel if not shut down already.
+			if (!this.channel.isShutdown()) {
+				try {
+					this.channel.shutdown();
+					if (!this.channel.awaitTermination(10, TimeUnit.SECONDS)) {
+						LOGGER.warn("Timed out gracefully shutting down connection: {}. ", this.channel);
+					}
+				} catch (Exception e) {
+					LOGGER.error("Unexpected exception while waiting for channel termination", e);
+				}
+			}
+
+			// Forceful shut down if still not terminated.
+			if (!this.channel.isTerminated()) {
+				try {
+					this.channel.shutdownNow();
+					if (!this.channel.awaitTermination(15, TimeUnit.SECONDS)) {
+						LOGGER.warn("Timed out forcefully shutting down connection: {}. ", this.channel);
+					}
+				} catch (Exception e) {
+					LOGGER.error("Unexpected exception while waiting for channel termination", e);
+				}
+			}
+
+			this.channel = null;
+			this.currentServer = null;
+		}
+	}
+
+	/** Closes connection to currently connected server (if any). */
+	private void closeServer() {
+		synchronized (this.serverLock) {
+			this.closeServer(this.currentServer);
+		}
+	}
+
+}

src/main/java/org/qortal/crosschain/PirateWallet.java

@@ -0,0 +1,409 @@
+package org.qortal.crosschain;
+
+import com.rust.litewalletjni.LiteWalletJni;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.bouncycastle.util.encoders.Base64;
+import org.bouncycastle.util.encoders.DecoderException;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.qortal.controller.PirateChainWalletController;
+import org.qortal.crypto.Crypto;
+import org.qortal.settings.Settings;
+import org.qortal.utils.Base58;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Objects;
+import java.util.Random;
+
+public class PirateWallet {
+
+    protected static final Logger LOGGER = LogManager.getLogger(PirateWallet.class);
+
+    private byte[] entropyBytes;
+    private final boolean isNullSeedWallet;
+    private String seedPhrase;
+    private boolean ready = false;
+
+    private String params;
+    private String saplingOutput64;
+    private String saplingSpend64;
+
+    private final static String COIN_PARAMS_FILENAME = "coinparams.json";
+    private final static String SAPLING_OUTPUT_FILENAME = "saplingoutput_base64";
+    private final static String SAPLING_SPEND_FILENAME = "saplingspend_base64";
+
+    public PirateWallet(byte[] entropyBytes, boolean isNullSeedWallet) throws IOException {
+        this.entropyBytes = entropyBytes;
+        this.isNullSeedWallet = isNullSeedWallet;
+
+        Path libDirectory = PirateChainWalletController.getRustLibOuterDirectory();
+        if (!Files.exists(Paths.get(libDirectory.toString(), COIN_PARAMS_FILENAME))) {
+            return;
+        }
+
+        this.params = Files.readString(Paths.get(libDirectory.toString(), COIN_PARAMS_FILENAME));
+        this.saplingOutput64 = Files.readString(Paths.get(libDirectory.toString(), SAPLING_OUTPUT_FILENAME));
+        this.saplingSpend64 = Files.readString(Paths.get(libDirectory.toString(), SAPLING_SPEND_FILENAME));
+
+        this.ready = this.initialize();
+    }
+
+    private boolean initialize() {
+        try {
+            LiteWalletJni.initlogging();
+
+            if (this.entropyBytes == null) {
+                return false;
+            }
+
+            // Pick a random server
+            PirateLightClient.Server server = this.getRandomServer();
+            String serverUri = String.format("https://%s:%d/", server.hostname, server.port);
+
+            // Pirate library uses base64 encoding
+            String entropy64 = Base64.toBase64String(this.entropyBytes);
+
+            // Derive seed phrase from entropy bytes
+            String inputSeedResponse = LiteWalletJni.getseedphrasefromentropyb64(entropy64);
+            JSONObject inputSeedJson =  new JSONObject(inputSeedResponse);
+            String inputSeedPhrase = null;
+            if (inputSeedJson.has("seedPhrase")) {
+                inputSeedPhrase = inputSeedJson.getString("seedPhrase");
+            }
+
+            String wallet = this.load();
+            if (wallet == null) {
+                // Wallet doesn't exist, so create a new one
+
+                int birthday = Settings.getInstance().getArrrDefaultBirthday();
+                if (this.isNullSeedWallet) {
+                    try {
+                        // Attempt to set birthday to the current block for null seed wallets
+                        birthday = PirateChain.getInstance().blockchainProvider.getCurrentHeight();
+                    }
+                    catch (ForeignBlockchainException e) {
+                        // Use the default height
+                    }
+                }
+
+                // Initialize new wallet
+                String birthdayString = String.format("%d", birthday);
+                String outputSeedResponse = LiteWalletJni.initfromseed(serverUri, this.params, inputSeedPhrase, birthdayString, this.saplingOutput64, this.saplingSpend64); // Thread-safe.
+                JSONObject outputSeedJson =  new JSONObject(outputSeedResponse);
+                String outputSeedPhrase = null;
+                if (outputSeedJson.has("seed")) {
+                    outputSeedPhrase = outputSeedJson.getString("seed");
+                }
+
+                // Ensure seed phrase in response matches supplied seed phrase
+                if (inputSeedPhrase == null || !Objects.equals(inputSeedPhrase, outputSeedPhrase)) {
+                    LOGGER.info("Unable to initialize Pirate Chain wallet: seed phrases do not match, or are null");
+                    return false;
+                }
+
+                this.seedPhrase = outputSeedPhrase;
+
+            } else {
+                // Restore existing wallet
+                String response = LiteWalletJni.initfromb64(serverUri, params, wallet, saplingOutput64, saplingSpend64);
+                if (response != null && !response.contains("\"initalized\":true")) {
+                    LOGGER.info("Unable to initialize Pirate Chain wallet: {}", response);
+                    return false;
+                }
+                this.seedPhrase = inputSeedPhrase;
+            }
+
+            // Check that we're able to communicate with the library
+            Integer ourHeight = this.getHeight();
+            return (ourHeight != null && ourHeight > 0);
+
+        } catch (IOException | JSONException | UnsatisfiedLinkError e) {
+            LOGGER.info("Unable to initialize Pirate Chain wallet: {}", e.getMessage());
+        }
+
+        return false;
+    }
+
+    public boolean isReady() {
+        return this.ready;
+    }
+
+    public void setReady(boolean ready) {
+        this.ready = ready;
+    }
+
+    public boolean entropyBytesEqual(byte[] testEntropyBytes) {
+        return Arrays.equals(testEntropyBytes, this.entropyBytes);
+    }
+
+    private void encrypt() {
+        if (this.isEncrypted()) {
+            // Nothing to do
+            return;
+        }
+
+        String encryptionKey = this.getEncryptionKey();
+        if (encryptionKey == null) {
+            // Can't encrypt without a key
+            return;
+        }
+
+        this.doEncrypt(encryptionKey);
+    }
+
+    private void decrypt() {
+        if (!this.isEncrypted()) {
+            // Nothing to do
+            return;
+        }
+
+        String encryptionKey = this.getEncryptionKey();
+        if (encryptionKey == null) {
+            // Can't encrypt without a key
+            return;
+        }
+
+        this.doDecrypt(encryptionKey);
+    }
+
+    public void unlock() {
+        if (!this.isEncrypted()) {
+            // Nothing to do
+            return;
+        }
+
+        String encryptionKey = this.getEncryptionKey();
+        if (encryptionKey == null) {
+            // Can't encrypt without a key
+            return;
+        }
+
+        this.doUnlock(encryptionKey);
+    }
+
+    public boolean save() throws IOException {
+        if (!isInitialized()) {
+            LOGGER.info("Error: can't save wallet, because no wallet it initialized");
+            return false;
+        }
+        if (this.isNullSeedWallet()) {
+            // Don't save wallets that have a null seed
+            return false;
+        }
+
+        // Encrypt first (will do nothing if already encrypted)
+        this.encrypt();
+
+        String wallet64 = LiteWalletJni.save();
+        byte[] wallet;
+        try {
+            wallet = Base64.decode(wallet64);
+        }
+        catch (DecoderException e) {
+            LOGGER.info("Unable to decode wallet");
+            return false;
+        }
+        if (wallet == null) {
+            LOGGER.info("Unable to save wallet");
+            return false;
+        }
+
+        Path walletPath = this.getCurrentWalletPath();
+        Files.createDirectories(walletPath.getParent());
+        Files.write(walletPath, wallet, StandardOpenOption.CREATE);
+
+        LOGGER.debug("Saved Pirate Chain wallet");
+
+        return true;
+    }
+
+    public String load() throws IOException {
+        if (this.isNullSeedWallet()) {
+            // Don't load wallets that have a null seed
+            return null;
+        }
+        Path walletPath = this.getCurrentWalletPath();
+        if (!Files.exists(walletPath)) {
+            return null;
+        }
+        byte[] wallet = Files.readAllBytes(walletPath);
+        if (wallet == null) {
+            return null;
+        }
+        String wallet64 = Base64.toBase64String(wallet);
+        return wallet64;
+    }
+
+    private String getEntropyHash58() {
+        if (this.entropyBytes == null) {
+            return null;
+        }
+        byte[] entropyHash = Crypto.digest(this.entropyBytes);
+        return Base58.encode(entropyHash);
+    }
+
+    public String getSeedPhrase() {
+        return this.seedPhrase;
+    }
+
+    private String getEncryptionKey() {
+        if (this.entropyBytes == null) {
+            return null;
+        }
+
+        // Prefix the bytes with a (deterministic) string, to ensure that the resulting hash is different
+        String prefix = "ARRRWalletEncryption";
+
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        try {
+            outputStream.write(prefix.getBytes(StandardCharsets.UTF_8));
+            outputStream.write(this.entropyBytes);
+
+        } catch (IOException e) {
+            return null;
+        }
+
+        byte[] encryptionKeyHash = Crypto.digest(outputStream.toByteArray());
+        return Base58.encode(encryptionKeyHash);
+    }
+
+    private Path getCurrentWalletPath() {
+        String entropyHash58 = this.getEntropyHash58();
+        String filename = String.format("wallet-%s.dat", entropyHash58);
+        return Paths.get(Settings.getInstance().getWalletsPath(), "PirateChain", filename);
+    }
+
+    public boolean isInitialized() {
+        return this.entropyBytes != null && this.ready;
+    }
+
+    public boolean isSynchronized() {
+        Integer height = this.getHeight();
+        Integer chainTip = this.getChainTip();
+
+        if (height == null || chainTip == null) {
+            return false;
+        }
+
+        // Assume synchronized if within 2 blocks of the chain tip
+        return height >= (chainTip - 2);
+    }
+
+
+    // APIs
+
+    public Integer getHeight() {
+        String response = LiteWalletJni.execute("height", "");
+        JSONObject json = new JSONObject(response);
+        if (json.has("height")) {
+            return json.getInt("height");
+        }
+        return null;
+    }
+
+    public Integer getChainTip() {
+        String response = LiteWalletJni.execute("info", "");
+        JSONObject json = new JSONObject(response);
+        if (json.has("latest_block_height")) {
+            return json.getInt("latest_block_height");
+        }
+        return null;
+    }
+
+    public boolean isNullSeedWallet() {
+        return this.isNullSeedWallet;
+    }
+
+    public Boolean isEncrypted() {
+        String response = LiteWalletJni.execute("encryptionstatus", "");
+        JSONObject json = new JSONObject(response);
+        if (json.has("encrypted")) {
+            return json.getBoolean("encrypted");
+        }
+        return null;
+    }
+
+    public boolean doEncrypt(String key) {
+        String response = LiteWalletJni.execute("encrypt", key);
+        JSONObject json = new JSONObject(response);
+        String result = json.getString("result");
+        if (json.has("result")) {
+            return (Objects.equals(result, "success"));
+        }
+        return false;
+    }
+
+    public boolean doDecrypt(String key) {
+        String response = LiteWalletJni.execute("decrypt", key);
+        JSONObject json = new JSONObject(response);
+        String result = json.getString("result");
+        if (json.has("result")) {
+            return (Objects.equals(result, "success"));
+        }
+        return false;
+    }
+
+    public boolean doUnlock(String key) {
+        String response = LiteWalletJni.execute("unlock", key);
+        JSONObject json = new JSONObject(response);
+        String result = json.getString("result");
+        if (json.has("result")) {
+            return (Objects.equals(result, "success"));
+        }
+        return false;
+    }
+
+    public String getWalletAddress() {
+        // Get balance, which also contains wallet addresses
+        String response = LiteWalletJni.execute("balance", "");
+        JSONObject json = new JSONObject(response);
+        String address = null;
+
+        if (json.has("z_addresses")) {
+            JSONArray z_addresses = json.getJSONArray("z_addresses");
+
+            if (z_addresses != null && !z_addresses.isEmpty()) {
+                JSONObject firstAddress = z_addresses.getJSONObject(0);
+                if (firstAddress.has("address")) {
+                    address = firstAddress.getString("address");
+                }
+            }
+        }
+        return address;
+    }
+
+    public String getPrivateKey() {
+        String response = LiteWalletJni.execute("export", "");
+        JSONArray addressesJson = new JSONArray(response);
+        if (!addressesJson.isEmpty()) {
+            JSONObject addressJson = addressesJson.getJSONObject(0);
+            if (addressJson.has("private_key")) {
+                //String address = addressJson.getString("address");
+                String privateKey = addressJson.getString("private_key");
+                //String viewingKey = addressJson.getString("viewing_key");
+
+                return privateKey;
+            }
+        }
+        return null;
+    }
+
+    public PirateLightClient.Server getRandomServer() {
+        PirateChain.PirateChainNet pirateChainNet = Settings.getInstance().getPirateChainNet();
+        Collection<PirateLightClient.Server> servers = pirateChainNet.getServers();
+        Random random = new Random();
+        int index = random.nextInt(servers.size());
+        return (PirateLightClient.Server) servers.toArray()[index];
+    }
+
+}

src/main/java/org/qortal/crosschain/SimpleTransaction.java

@@ -7,11 +7,12 @@ import java.util.List;
 @XmlAccessorType(XmlAccessType.FIELD)
 public class SimpleTransaction {
     private String txHash;
-    private Integer timestamp;
+    private Long timestamp;
     private long totalAmount;
     private long feeAmount;
     private List<Input> inputs;
     private List<Output> outputs;
+    private String memo;
 
 
     @XmlAccessorType(XmlAccessType.FIELD)
@@ -74,20 +75,21 @@ public class SimpleTransaction {
     public SimpleTransaction() {
     }
 
-    public SimpleTransaction(String txHash, Integer timestamp, long totalAmount, long feeAmount, List<Input> inputs, List<Output> outputs) {
+    public SimpleTransaction(String txHash, Long timestamp, long totalAmount, long feeAmount, List<Input> inputs, List<Output> outputs, String memo) {
         this.txHash = txHash;
         this.timestamp = timestamp;
         this.totalAmount = totalAmount;
         this.feeAmount = feeAmount;
         this.inputs = inputs;
         this.outputs = outputs;
+        this.memo = memo;
     }
 
     public String getTxHash() {
         return txHash;
     }
 
-    public Integer getTimestamp() {
+    public Long getTimestamp() {
         return timestamp;
     }
 

src/main/java/org/qortal/crosschain/SupportedBlockchain.java

@@ -13,8 +13,8 @@ import org.qortal.utils.Triple;
 public enum SupportedBlockchain {
 
 	BITCOIN(Arrays.asList(
-				Triple.valueOf(BitcoinACCTv1.NAME, BitcoinACCTv1.CODE_BYTES_HASH, BitcoinACCTv1::getInstance)
-				// Could add improved BitcoinACCTv2 here in the future
+				Triple.valueOf(BitcoinACCTv1.NAME, BitcoinACCTv1.CODE_BYTES_HASH, BitcoinACCTv1::getInstance),
+				Triple.valueOf(BitcoinACCTv3.NAME, BitcoinACCTv3.CODE_BYTES_HASH, BitcoinACCTv3::getInstance)
 			)) {
 		@Override
 		public ForeignBlockchain getInstance() {
@@ -23,13 +23,12 @@ public enum SupportedBlockchain {
 
 		@Override
 		public ACCT getLatestAcct() {
-			return BitcoinACCTv1.getInstance();
+			return BitcoinACCTv3.getInstance();
 		}
 	},
 
 	LITECOIN(Arrays.asList(
 			Triple.valueOf(LitecoinACCTv1.NAME, LitecoinACCTv1.CODE_BYTES_HASH, LitecoinACCTv1::getInstance),
-			Triple.valueOf(LitecoinACCTv2.NAME, LitecoinACCTv2.CODE_BYTES_HASH, LitecoinACCTv2::getInstance),
 			Triple.valueOf(LitecoinACCTv3.NAME, LitecoinACCTv3.CODE_BYTES_HASH, LitecoinACCTv3::getInstance)
 		)) {
 		@Override
@@ -45,7 +44,6 @@ public enum SupportedBlockchain {
 
 	DOGECOIN(Arrays.asList(
 			Triple.valueOf(DogecoinACCTv1.NAME, DogecoinACCTv1.CODE_BYTES_HASH, DogecoinACCTv1::getInstance),
-			Triple.valueOf(DogecoinACCTv2.NAME, DogecoinACCTv2.CODE_BYTES_HASH, DogecoinACCTv2::getInstance),
 			Triple.valueOf(DogecoinACCTv3.NAME, DogecoinACCTv3.CODE_BYTES_HASH, DogecoinACCTv3::getInstance)
 		)) {
 		@Override
@@ -59,6 +57,20 @@ public enum SupportedBlockchain {
 		}
 	},
 
+	DIGIBYTE(Arrays.asList(
+			Triple.valueOf(DigibyteACCTv3.NAME, DigibyteACCTv3.CODE_BYTES_HASH, DigibyteACCTv3::getInstance)
+		)) {
+		@Override
+		public ForeignBlockchain getInstance() {
+			return Digibyte.getInstance();
+		}
+
+		@Override
+		public ACCT getLatestAcct() {
+			return DigibyteACCTv3.getInstance();
+		}
+	},
+
 	RAVENCOIN(Arrays.asList(
 			Triple.valueOf(RavencoinACCTv3.NAME, RavencoinACCTv3.CODE_BYTES_HASH, RavencoinACCTv3::getInstance)
 		)) {
@@ -71,6 +83,20 @@ public enum SupportedBlockchain {
 		public ACCT getLatestAcct() {
 			return RavencoinACCTv3.getInstance();
 		}
+	},
+
+	PIRATECHAIN(Arrays.asList(
+			Triple.valueOf(PirateChainACCTv3.NAME, PirateChainACCTv3.CODE_BYTES_HASH, PirateChainACCTv3::getInstance)
+	)) {
+		@Override
+		public ForeignBlockchain getInstance() {
+			return PirateChain.getInstance();
+		}
+
+		@Override
+		public ACCT getLatestAcct() {
+			return PirateChainACCTv3.getInstance();
+		}
 	};
 
 	private static final Map<ByteArray, Supplier<ACCT>> supportedAcctsByCodeHash = Arrays.stream(SupportedBlockchain.values())

src/main/java/org/qortal/crosschain/UnspentOutput.java

@@ -7,10 +7,20 @@ public class UnspentOutput {
 	public final int height;
 	public final long value;
 
-	public UnspentOutput(byte[] hash, int index, int height, long value) {
+	// Optional fields returned by Pirate Light Client server
+	public final byte[] script;
+	public final String address;
+
+	public UnspentOutput(byte[] hash, int index, int height, long value, byte[] script, String address) {
 		this.hash = hash;
 		this.index = index;
 		this.height = height;
 		this.value = value;
+		this.script = script;
+		this.address = address;
+	}
+
+	public UnspentOutput(byte[] hash, int index, int height, long value) {
+		this(hash, index, height, value, null, null);
 	}
 }

src/main/java/org/qortal/crypto/BouncyCastle25519.java

@@ -1,99 +0,0 @@
-package org.qortal.crypto;
-
-import java.lang.reflect.Constructor;
-import java.lang.reflect.Field;
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.util.Arrays;
-
-import org.bouncycastle.crypto.Digest;
-import org.bouncycastle.math.ec.rfc7748.X25519;
-import org.bouncycastle.math.ec.rfc7748.X25519Field;
-import org.bouncycastle.math.ec.rfc8032.Ed25519;
-
-/** Additions to BouncyCastle providing Ed25519 to X25519 key conversion. */
-public class BouncyCastle25519 {
-
-	private static final Class<?> pointAffineClass;
-	private static final Constructor<?> pointAffineCtor;
-	private static final Method decodePointVarMethod;
-	private static final Field yField;
-
-	static {
-		try {
-			Class<?> ed25519Class = Ed25519.class;
-			pointAffineClass = Arrays.stream(ed25519Class.getDeclaredClasses()).filter(clazz -> clazz.getSimpleName().equals("PointAffine")).findFirst().get();
-			if (pointAffineClass == null)
-				throw new ClassNotFoundException("Can't locate PointExt inner class inside Ed25519");
-
-			decodePointVarMethod = ed25519Class.getDeclaredMethod("decodePointVar", byte[].class, int.class, boolean.class, pointAffineClass);
-			decodePointVarMethod.setAccessible(true);
-
-			pointAffineCtor = pointAffineClass.getDeclaredConstructors()[0];
-			pointAffineCtor.setAccessible(true);
-
-			yField = pointAffineClass.getDeclaredField("y");
-			yField.setAccessible(true);
-		} catch (NoSuchMethodException | SecurityException | IllegalArgumentException | NoSuchFieldException | ClassNotFoundException e) {
-			throw new RuntimeException("Can't initialize BouncyCastle25519 shim", e);
-		}
-	}
-
-	private static int[] obtainYFromPublicKey(byte[] ed25519PublicKey) {
-		try {
-			Object pA = pointAffineCtor.newInstance();
-
-			Boolean result = (Boolean) decodePointVarMethod.invoke(null, ed25519PublicKey, 0, true, pA);
-			if (result == null || !result)
-				return null;
-
-			return (int[]) yField.get(pA);
-		} catch (SecurityException | InstantiationException | IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
-			throw new RuntimeException("Can't reflect into BouncyCastle", e);
-		}
-	}
-
-	public static byte[] toX25519PublicKey(byte[] ed25519PublicKey) {
-		int[] one = new int[X25519Field.SIZE];
-		X25519Field.one(one);
-
-		int[] y = obtainYFromPublicKey(ed25519PublicKey);
-
-		int[] oneMinusY = new int[X25519Field.SIZE];
-		X25519Field.sub(one, y, oneMinusY);
-
-		int[] onePlusY = new int[X25519Field.SIZE];
-		X25519Field.add(one, y, onePlusY);
-
-		int[] oneMinusYInverted = new int[X25519Field.SIZE];
-		X25519Field.inv(oneMinusY, oneMinusYInverted);
-
-		int[] u = new int[X25519Field.SIZE];
-		X25519Field.mul(onePlusY, oneMinusYInverted, u);
-
-		X25519Field.normalize(u);
-
-		byte[] x25519PublicKey = new byte[X25519.SCALAR_SIZE];
-		X25519Field.encode(u, x25519PublicKey, 0);
-
-		return x25519PublicKey;
-	}
-
-	public static byte[] toX25519PrivateKey(byte[] ed25519PrivateKey) {
-		Digest d = Ed25519.createPrehash();
-		byte[] h = new byte[d.getDigestSize()];
-
-		d.update(ed25519PrivateKey, 0, ed25519PrivateKey.length);
-		d.doFinal(h, 0);
-
-		byte[] s = new byte[X25519.SCALAR_SIZE];
-
-		System.arraycopy(h, 0, s, 0, X25519.SCALAR_SIZE);
-		s[0] &= 0xF8;
-		s[X25519.SCALAR_SIZE - 1] &= 0x7F;
-		s[X25519.SCALAR_SIZE - 1] |= 0x40;
-
-		return s;
-	}
-
-}

src/main/java/org/qortal/crypto/Crypto.java

@@ -253,6 +253,10 @@ public abstract class Crypto {
 		return false;
 	}
 
+	public static byte[] toPublicKey(byte[] privateKey) {
+		return new Ed25519PrivateKeyParameters(privateKey, 0).generatePublicKey().getEncoded();
+	}
+
 	public static boolean verify(byte[] publicKey, byte[] signature, byte[] message) {
 		try {
 			return Ed25519.verify(signature, 0, publicKey, 0, message, 0, message.length);
@@ -264,16 +268,24 @@ public abstract class Crypto {
 	public static byte[] sign(Ed25519PrivateKeyParameters edPrivateKeyParams, byte[] message) {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 
-		edPrivateKeyParams.sign(Ed25519.Algorithm.Ed25519, edPrivateKeyParams.generatePublicKey(), null, message, 0, message.length, signature, 0);
+		edPrivateKeyParams.sign(Ed25519.Algorithm.Ed25519,null, message, 0, message.length, signature, 0);
+
+		return signature;
+	}
+
+	public static byte[] sign(byte[] privateKey, byte[] message) {
+		byte[] signature = new byte[SIGNATURE_LENGTH];
+
+		new Ed25519PrivateKeyParameters(privateKey, 0).sign(Ed25519.Algorithm.Ed25519,null, message, 0, message.length, signature, 0);
 
 		return signature;
 	}
 
 	public static byte[] getSharedSecret(byte[] privateKey, byte[] publicKey) {
-		byte[] x25519PrivateKey = BouncyCastle25519.toX25519PrivateKey(privateKey);
+		byte[] x25519PrivateKey = Qortal25519Extras.toX25519PrivateKey(privateKey);
 		X25519PrivateKeyParameters xPrivateKeyParams = new X25519PrivateKeyParameters(x25519PrivateKey, 0);
 
-		byte[] x25519PublicKey = BouncyCastle25519.toX25519PublicKey(publicKey);
+		byte[] x25519PublicKey = Qortal25519Extras.toX25519PublicKey(publicKey);
 		X25519PublicKeyParameters xPublicKeyParams = new X25519PublicKeyParameters(x25519PublicKey, 0);
 
 		byte[] sharedSecret = new byte[SHARED_SECRET_LENGTH];
@@ -281,5 +293,4 @@ public abstract class Crypto {
 
 		return sharedSecret;
 	}
-
 }

src/main/java/org/qortal/crypto/MemoryPoW.java

@@ -1,10 +1,44 @@
 package org.qortal.crypto;
 
+import org.qortal.utils.NTP;
+
 import java.nio.ByteBuffer;
+import java.util.concurrent.TimeoutException;
 
 public class MemoryPoW {
 
+	/**
+	 * Compute a MemoryPoW nonce
+	 *
+	 * @param data
+	 * @param workBufferLength
+	 * @param difficulty
+	 * @return
+	 * @throws TimeoutException
+	 */
 	public static Integer compute2(byte[] data, int workBufferLength, long difficulty) {
+		try {
+			return MemoryPoW.compute2(data, workBufferLength, difficulty, null);
+
+		} catch (TimeoutException e) {
+			// This won't happen, because above timeout is null
+			return null;
+		}
+	}
+
+	/**
+	 * Compute a MemoryPoW nonce, with optional timeout
+	 *
+	 * @param data
+	 * @param workBufferLength
+	 * @param difficulty
+	 * @param timeout maximum number of milliseconds to compute for before giving up,<br>or null if no timeout
+	 * @return
+	 * @throws TimeoutException
+	 */
+	public static Integer compute2(byte[] data, int workBufferLength, long difficulty, Long timeout) throws TimeoutException {
+		long startTime = NTP.getTime();
+
 		// Hash data with SHA256
 		byte[] hash = Crypto.digest(data);
 
@@ -33,6 +67,13 @@ public class MemoryPoW {
 			if (Thread.currentThread().isInterrupted())
 				return -1;
 
+			if (timeout != null) {
+				long now = NTP.getTime();
+				if (now > startTime + timeout) {
+					throw new TimeoutException("Timeout reached");
+				}
+			}
+
 			seed *= seedMultiplier; // per nonce
 
 			state[0] = longHash[0] ^ seed;

src/main/java/org/qortal/crypto/Qortal25519Extras.java

@@ -0,0 +1,234 @@
+package org.qortal.crypto;
+
+import org.bouncycastle.crypto.Digest;
+import org.bouncycastle.crypto.digests.SHA512Digest;
+import org.bouncycastle.math.ec.rfc7748.X25519;
+import org.bouncycastle.math.ec.rfc7748.X25519Field;
+import org.bouncycastle.math.ec.rfc8032.Ed25519;
+import org.bouncycastle.math.raw.Nat256;
+
+import java.security.SecureRandom;
+import java.util.Arrays;
+import java.util.Collection;
+
+/**
+ * Additions to BouncyCastle providing:
+ * <p></p>
+ * <ul>
+ *     <li>Ed25519 to X25519 key conversion</li>
+ *     <li>Aggregate public keys</li>
+ *     <li>Aggregate signatures</li>
+ * </ul>
+ */
+public abstract class Qortal25519Extras extends BouncyCastleEd25519 {
+
+	private static final SecureRandom SECURE_RANDOM = new SecureRandom();
+
+	public static byte[] toX25519PublicKey(byte[] ed25519PublicKey) {
+		int[] one = new int[X25519Field.SIZE];
+		X25519Field.one(one);
+
+		PointAffine pA = new PointAffine();
+		if (!decodePointVar(ed25519PublicKey, 0, true, pA))
+			return null;
+
+		int[] y = pA.y;
+
+		int[] oneMinusY = new int[X25519Field.SIZE];
+		X25519Field.sub(one, y, oneMinusY);
+
+		int[] onePlusY = new int[X25519Field.SIZE];
+		X25519Field.add(one, y, onePlusY);
+
+		int[] oneMinusYInverted = new int[X25519Field.SIZE];
+		X25519Field.inv(oneMinusY, oneMinusYInverted);
+
+		int[] u = new int[X25519Field.SIZE];
+		X25519Field.mul(onePlusY, oneMinusYInverted, u);
+
+		X25519Field.normalize(u);
+
+		byte[] x25519PublicKey = new byte[X25519.SCALAR_SIZE];
+		X25519Field.encode(u, x25519PublicKey, 0);
+
+		return x25519PublicKey;
+	}
+
+	public static byte[] toX25519PrivateKey(byte[] ed25519PrivateKey) {
+		Digest d = Ed25519.createPrehash();
+		byte[] h = new byte[d.getDigestSize()];
+
+		d.update(ed25519PrivateKey, 0, ed25519PrivateKey.length);
+		d.doFinal(h, 0);
+
+		byte[] s = new byte[X25519.SCALAR_SIZE];
+
+		System.arraycopy(h, 0, s, 0, X25519.SCALAR_SIZE);
+		s[0] &= 0xF8;
+		s[X25519.SCALAR_SIZE - 1] &= 0x7F;
+		s[X25519.SCALAR_SIZE - 1] |= 0x40;
+
+		return s;
+	}
+
+	// Mostly for test support
+	public static PointAccum newPointAccum() {
+		return new PointAccum();
+	}
+
+	public static byte[] aggregatePublicKeys(Collection<byte[]> publicKeys) {
+		PointAccum rAccum = null;
+
+		for (byte[] publicKey : publicKeys) {
+			PointAffine pA = new PointAffine();
+			if (!decodePointVar(publicKey, 0, false, pA))
+				// Failed to decode
+				return null;
+
+			if (rAccum == null) {
+				rAccum = new PointAccum();
+				pointCopy(pA, rAccum);
+			} else {
+				pointAdd(pointCopy(pA), rAccum);
+			}
+		}
+
+		byte[] publicKey = new byte[SCALAR_BYTES];
+		if (0 == encodePoint(rAccum, publicKey, 0))
+			// Failed to encode
+			return null;
+
+		return publicKey;
+	}
+
+	public static byte[] aggregateSignatures(Collection<byte[]> signatures) {
+		// Signatures are (R, s)
+		// R is a point
+		// s is a scalar
+		PointAccum rAccum = null;
+		int[] sAccum = new int[SCALAR_INTS];
+
+		byte[] rEncoded = new byte[POINT_BYTES];
+		int[] sPart = new int[SCALAR_INTS];
+		for (byte[] signature : signatures) {
+			System.arraycopy(signature,0, rEncoded, 0, rEncoded.length);
+
+			PointAffine pA = new PointAffine();
+			if (!decodePointVar(rEncoded, 0, false, pA))
+				// Failed to decode
+				return null;
+
+			if (rAccum == null) {
+				rAccum = new PointAccum();
+				pointCopy(pA, rAccum);
+
+				decode32(signature, rEncoded.length, sAccum, 0, SCALAR_INTS);
+			} else {
+				pointAdd(pointCopy(pA), rAccum);
+
+				decode32(signature, rEncoded.length, sPart, 0, SCALAR_INTS);
+				Nat256.addTo(sPart, sAccum);
+
+				// "mod L" on sAccum
+				if (Nat256.gte(sAccum, L))
+					Nat256.subFrom(L, sAccum);
+			}
+		}
+
+		byte[] signature = new byte[SIGNATURE_SIZE];
+		if (0 == encodePoint(rAccum, signature, 0))
+			// Failed to encode
+			return null;
+
+		for (int i = 0; i < sAccum.length; ++i) {
+			encode32(sAccum[i], signature, POINT_BYTES + i * 4);
+		}
+
+		return signature;
+	}
+
+	public static byte[] signForAggregation(byte[] privateKey, byte[] message) {
+		// Very similar to BouncyCastle's implementation except we use secure random nonce and different hash
+		Digest d = new SHA512Digest();
+		byte[] h = new byte[d.getDigestSize()];
+
+		d.reset();
+		d.update(privateKey, 0, privateKey.length);
+		d.doFinal(h, 0);
+
+		byte[] sH = new byte[SCALAR_BYTES];
+		pruneScalar(h, 0, sH);
+
+		byte[] publicKey = new byte[SCALAR_BYTES];
+		scalarMultBaseEncoded(sH, publicKey, 0);
+
+		byte[] rSeed = new byte[d.getDigestSize()];
+		SECURE_RANDOM.nextBytes(rSeed);
+
+		byte[] r = new byte[SCALAR_BYTES];
+		pruneScalar(rSeed, 0, r);
+
+		byte[] R = new byte[POINT_BYTES];
+		scalarMultBaseEncoded(r, R, 0);
+
+		d.reset();
+		d.update(message, 0, message.length);
+		d.doFinal(h, 0);
+		byte[] k = reduceScalar(h);
+
+		byte[] s = calculateS(r, k, sH);
+
+		byte[] signature = new byte[SIGNATURE_SIZE];
+		System.arraycopy(R, 0, signature, 0, POINT_BYTES);
+		System.arraycopy(s, 0, signature, POINT_BYTES, SCALAR_BYTES);
+
+		return signature;
+	}
+
+	public static boolean verifyAggregated(byte[] publicKey, byte[] signature, byte[] message) {
+		byte[] R = Arrays.copyOfRange(signature, 0, POINT_BYTES);
+
+		byte[] s = Arrays.copyOfRange(signature, POINT_BYTES, POINT_BYTES + SCALAR_BYTES);
+
+		if (!checkPointVar(R))
+			// R out of bounds
+			return false;
+
+		if (!checkScalarVar(s))
+			// s out of bounds
+			return false;
+
+		byte[] S = new byte[POINT_BYTES];
+		scalarMultBaseEncoded(s, S, 0);
+
+		PointAffine pA = new PointAffine();
+		if (!decodePointVar(publicKey, 0, true, pA))
+			// Failed to decode
+			return false;
+
+		Digest d = new SHA512Digest();
+		byte[] h = new byte[d.getDigestSize()];
+
+		d.update(message, 0, message.length);
+		d.doFinal(h, 0);
+
+		byte[] k = reduceScalar(h);
+
+		int[] nS = new int[SCALAR_INTS];
+		decodeScalar(s, 0, nS);
+
+		int[] nA = new int[SCALAR_INTS];
+		decodeScalar(k, 0, nA);
+
+		/*PointAccum*/
+		PointAccum pR = new PointAccum();
+		scalarMultStrausVar(nS, nA, pA, pR);
+
+		byte[] check = new byte[POINT_BYTES];
+		if (0 == encodePoint(pR, check, 0))
+			// Failed to encode
+			return false;
+
+		return Arrays.equals(check, R);
+	}
+}

src/main/java/org/qortal/data/arbitrary/ArbitraryResourceMetadata.java

@@ -24,7 +24,10 @@ public class ArbitraryResourceMetadata {
         this.description = description;
         this.tags = tags;
         this.category = category;
-        this.categoryName = category.getName();
+
+        if (category != null) {
+            this.categoryName = category.getName();
+        }
     }
 
     public static ArbitraryResourceMetadata fromTransactionMetadata(ArbitraryDataTransactionMetadata transactionMetadata) {

src/main/java/org/qortal/data/arbitrary/ArbitraryResourceStatus.java

@@ -26,6 +26,7 @@ public class ArbitraryResourceStatus {
         }
     }
 
+    private Status status;
     private String id;
     private String title;
     private String description;
@@ -37,6 +38,7 @@ public class ArbitraryResourceStatus {
     }
 
     public ArbitraryResourceStatus(Status status, Integer localChunkCount, Integer totalChunkCount) {
+        this.status = status;
         this.id = status.toString();
         this.title = status.title;
         this.description = status.description;
@@ -47,4 +49,20 @@ public class ArbitraryResourceStatus {
     public ArbitraryResourceStatus(Status status) {
         this(status, null, null);
     }
+
+    public Status getStatus() {
+        return this.status;
+    }
+
+    public String getTitle() {
+        return this.title;
+    }
+
+    public Integer getLocalChunkCount() {
+        return this.localChunkCount;
+    }
+
+    public Integer getTotalChunkCount() {
+        return this.totalChunkCount;
+    }
 }

src/main/java/org/qortal/data/block/BlockData.java

@@ -211,6 +211,14 @@ public class BlockData implements Serializable {
 		this.onlineAccountsSignatures = onlineAccountsSignatures;
 	}
 
+	public int getOnlineAccountsSignaturesCount() {
+		if (this.onlineAccountsSignatures != null && this.onlineAccountsSignatures.length > 0) {
+			// Blocks use a single online accounts signature, so there is no need for this to be dynamic
+			return 1;
+		}
+		return 0;
+	}
+
 	public boolean isTrimmed() {
 		long onlineAccountSignaturesTrimmedTimestamp = NTP.getTime() - BlockChain.getInstance().getOnlineAccountSignaturesMaxLifetime();
 		long currentTrimmableTimestamp = NTP.getTime() - Settings.getInstance().getAtStatesMaxLifetime();

src/main/java/org/qortal/data/block/BlockSummaryData.java

@@ -11,11 +11,12 @@ public class BlockSummaryData {
 	private int height;
 	private byte[] signature;
 	private byte[] minterPublicKey;
-	private int onlineAccountsCount;
 
 	// Optional, set during construction
+	private Integer onlineAccountsCount;
 	private Long timestamp;
 	private Integer transactionCount;
+	private byte[] reference;
 
 	// Optional, set after construction
 	private Integer minterLevel;
@@ -25,6 +26,15 @@ public class BlockSummaryData {
 	protected BlockSummaryData() {
 	}
 
+	/** Constructor typically populated with fields from HeightV2Message */
+	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, long timestamp) {
+		this.height = height;
+		this.signature = signature;
+		this.minterPublicKey = minterPublicKey;
+		this.timestamp = timestamp;
+	}
+
+	/** Constructor typically populated with fields from BlockSummariesMessage */
 	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, int onlineAccountsCount) {
 		this.height = height;
 		this.signature = signature;
@@ -32,13 +42,16 @@ public class BlockSummaryData {
 		this.onlineAccountsCount = onlineAccountsCount;
 	}
 
-	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, int onlineAccountsCount, long timestamp, int transactionCount) {
+	/** Constructor typically populated with fields from BlockSummariesV2Message */
+	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, Integer onlineAccountsCount,
+							Long timestamp, Integer transactionCount, byte[] reference) {
 		this.height = height;
 		this.signature = signature;
 		this.minterPublicKey = minterPublicKey;
 		this.onlineAccountsCount = onlineAccountsCount;
 		this.timestamp = timestamp;
 		this.transactionCount = transactionCount;
+		this.reference = reference;
 	}
 
 	public BlockSummaryData(BlockData blockData) {
@@ -49,6 +62,7 @@ public class BlockSummaryData {
 
 		this.timestamp = blockData.getTimestamp();
 		this.transactionCount = blockData.getTransactionCount();
+		this.reference = blockData.getReference();
 	}
 
 	// Getters / setters
@@ -65,7 +79,7 @@ public class BlockSummaryData {
 		return this.minterPublicKey;
 	}
 
-	public int getOnlineAccountsCount() {
+	public Integer getOnlineAccountsCount() {
 		return this.onlineAccountsCount;
 	}
 
@@ -77,6 +91,10 @@ public class BlockSummaryData {
 		return this.transactionCount;
 	}
 
+	public byte[] getReference() {
+		return this.reference;
+	}
+
 	public Integer getMinterLevel() {
 		return this.minterLevel;
 	}

src/main/java/org/qortal/data/block/CommonBlockData.java

@@ -1,7 +1,5 @@
 package org.qortal.data.block;
 
-import org.qortal.data.network.PeerChainTipData;
-
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 import java.math.BigInteger;
@@ -14,14 +12,14 @@ public class CommonBlockData {
 	private BlockSummaryData commonBlockSummary = null;
 	private List<BlockSummaryData> blockSummariesAfterCommonBlock = null;
 	private BigInteger chainWeight = null;
-	private PeerChainTipData chainTipData = null;
+	private BlockSummaryData chainTipData = null;
 
 	// Constructors
 
 	protected CommonBlockData() {
 	}
 
-	public CommonBlockData(BlockSummaryData commonBlockSummary, PeerChainTipData chainTipData) {
+	public CommonBlockData(BlockSummaryData commonBlockSummary, BlockSummaryData chainTipData) {
 		this.commonBlockSummary = commonBlockSummary;
 		this.chainTipData = chainTipData;
 	}
@@ -49,7 +47,7 @@ public class CommonBlockData {
 		this.chainWeight = chainWeight;
 	}
 
-	public PeerChainTipData getChainTipData() {
+	public BlockSummaryData getChainTipData() {
 		return this.chainTipData;
 	}
 

src/main/java/org/qortal/data/network/OnlineAccountData.java

@@ -5,6 +5,7 @@ import java.util.Arrays;
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlTransient;
 
 import org.qortal.account.PublicKeyAccount;
 
@@ -15,6 +16,10 @@ public class OnlineAccountData {
 	protected long timestamp;
 	protected byte[] signature;
 	protected byte[] publicKey;
+	protected Integer nonce;
+
+	@XmlTransient
+	private int hash;
 
 	// Constructors
 
@@ -22,10 +27,15 @@ public class OnlineAccountData {
 	protected OnlineAccountData() {
 	}
 
-	public OnlineAccountData(long timestamp, byte[] signature, byte[] publicKey) {
+	public OnlineAccountData(long timestamp, byte[] signature, byte[] publicKey, Integer nonce) {
 		this.timestamp = timestamp;
 		this.signature = signature;
 		this.publicKey = publicKey;
+		this.nonce = nonce;
+	}
+
+	public OnlineAccountData(long timestamp, byte[] signature, byte[] publicKey) {
+		this(timestamp, signature, publicKey, null);
 	}
 
 	public long getTimestamp() {
@@ -40,6 +50,10 @@ public class OnlineAccountData {
 		return this.publicKey;
 	}
 
+	public Integer getNonce() {
+		return this.nonce;
+	}
+
 	// For JAXB
 	@XmlElement(name = "address")
 	protected String getAddress() {
@@ -62,20 +76,23 @@ public class OnlineAccountData {
 		if (otherOnlineAccountData.timestamp != this.timestamp)
 			return false;
 
-		// Signature more likely to be unique than public key
-		if (!Arrays.equals(otherOnlineAccountData.signature, this.signature))
-			return false;
-
 		if (!Arrays.equals(otherOnlineAccountData.publicKey, this.publicKey))
 			return false;
 
+		// We don't compare signature because it's not our remit to verify and newer aggregate signatures use random nonces
+
 		return true;
 	}
 
 	@Override
 	public int hashCode() {
-		// Pretty lazy implementation
-		return (int) this.timestamp;
+		int h = this.hash;
+		if (h == 0) {
+			this.hash = h = Long.hashCode(this.timestamp)
+					^ Arrays.hashCode(this.publicKey);
+			// We don't use signature because newer aggregate signatures use random nonces
+		}
+		return h;
 	}
 
 }

src/main/java/org/qortal/data/network/PeerChainTipData.java

@@ -1,37 +0,0 @@
-package org.qortal.data.network;
-
-public class PeerChainTipData {
-
-	/** Latest block height as reported by peer. */
-	private Integer lastHeight;
-	/** Latest block signature as reported by peer. */
-	private byte[] lastBlockSignature;
-	/** Latest block timestamp as reported by peer. */
-	private Long lastBlockTimestamp;
-	/** Latest block minter public key as reported by peer. */
-	private byte[] lastBlockMinter;
-
-	public PeerChainTipData(Integer lastHeight, byte[] lastBlockSignature, Long lastBlockTimestamp, byte[] lastBlockMinter) {
-		this.lastHeight = lastHeight;
-		this.lastBlockSignature = lastBlockSignature;
-		this.lastBlockTimestamp = lastBlockTimestamp;
-		this.lastBlockMinter = lastBlockMinter;
-	}
-
-	public Integer getLastHeight() {
-		return this.lastHeight;
-	}
-
-	public byte[] getLastBlockSignature() {
-		return this.lastBlockSignature;
-	}
-
-	public Long getLastBlockTimestamp() {
-		return this.lastBlockTimestamp;
-	}
-
-	public byte[] getLastBlockMinter() {
-		return this.lastBlockMinter;
-	}
-
-}

src/main/java/org/qortal/gui/Gui.java

@@ -47,12 +47,12 @@ public class Gui {
 		this.splashFrame = SplashFrame.getInstance();
 	}
 
-	protected static BufferedImage loadImage(String resourceName) throws IOException {
+	protected static BufferedImage loadImage(String resourceName) {
 		try (InputStream in = Gui.class.getResourceAsStream("/images/" + resourceName)) {
 			return ImageIO.read(in);
 		} catch (IllegalArgumentException | IOException | ServiceConfigurationError e) {
 			LOGGER.warn(String.format("Couldn't locate image resource \"images/%s\"", resourceName));
-			throw new IOException(String.format("Couldn't locate image resource \"images/%s\"", resourceName));
+			return null;
 		}
 	}
 

src/main/java/org/qortal/gui/SplashFrame.java

@@ -1,7 +1,6 @@
 package org.qortal.gui;
 
 import java.awt.*;
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.awt.image.BufferedImage;
@@ -30,23 +29,18 @@ public class SplashFrame {
 		private JLabel statusLabel;
 
 		public SplashPanel() {
-			try {
-				image = Gui.loadImage(defaultSplash);
-
-				// Add logo
-				JLabel imageLabel = new JLabel(new ImageIcon(image));
-				imageLabel.setSize(new Dimension(300, 300));
-				add(imageLabel);
-			}
-			catch (IOException e) {
-				LOGGER.warn("Unable to load splash panel image");
-			}
+			image = Gui.loadImage(defaultSplash);
 
 			setOpaque(true);
 			setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
 			setBorder(new EmptyBorder(10, 10, 10, 10));
 			setBackground(Color.BLACK);
 
+			// Add logo
+			JLabel imageLabel = new JLabel(new ImageIcon(image));
+			imageLabel.setSize(new Dimension(300, 300));
+			add(imageLabel);
+
 			// Add spacing
 			add(Box.createRigidArea(new Dimension(0, 16)));
 
@@ -81,20 +75,15 @@ public class SplashFrame {
 
 		this.splashDialog = new JFrame();
 
-		try {
-			List<Image> icons = new ArrayList<>();
-			icons.add(Gui.loadImage("icons/icon16.png"));
-			icons.add(Gui.loadImage("icons/qortal_ui_tray_synced.png"));
-			icons.add(Gui.loadImage("icons/qortal_ui_tray_syncing_time-alt.png"));
-			icons.add(Gui.loadImage("icons/qortal_ui_tray_minting.png"));
-			icons.add(Gui.loadImage("icons/qortal_ui_tray_syncing.png"));
-			icons.add(Gui.loadImage("icons/icon64.png"));
-			icons.add(Gui.loadImage("icons/Qlogo_128.png"));
-			this.splashDialog.setIconImages(icons);
-		}
-		catch (IOException e) {
-			LOGGER.warn("Unable to load splash frame icons");
-		}
+		List<Image> icons = new ArrayList<>();
+		icons.add(Gui.loadImage("icons/icon16.png"));
+		icons.add(Gui.loadImage("icons/qortal_ui_tray_synced.png"));
+		icons.add(Gui.loadImage("icons/qortal_ui_tray_syncing_time-alt.png"));
+		icons.add(Gui.loadImage("icons/qortal_ui_tray_minting.png"));
+		icons.add(Gui.loadImage("icons/qortal_ui_tray_syncing.png"));
+		icons.add(Gui.loadImage("icons/icon64.png"));
+		icons.add(Gui.loadImage("icons/Qlogo_128.png"));
+		this.splashDialog.setIconImages(icons);
 
 		this.splashPanel = new SplashPanel();
 		this.splashDialog.getContentPane().add(this.splashPanel);

src/main/java/org/qortal/gui/SysTray.java

@@ -23,6 +23,7 @@ import java.util.List;
 
 import javax.swing.JDialog;
 import javax.swing.JMenuItem;
+import javax.swing.JOptionPane;
 import javax.swing.JPopupMenu;
 import javax.swing.SwingWorker;
 import javax.swing.event.PopupMenuEvent;
@@ -61,13 +62,7 @@ public class SysTray {
 		this.popupMenu = createJPopupMenu();
 
 		// Build TrayIcon without AWT PopupMenu (which doesn't support Unicode)...
-		try {
-			this.trayIcon = new TrayIcon(Gui.loadImage("icons/qortal_ui_tray_synced.png"), "qortal", null);
-		}
-		catch (IOException e) {
-			LOGGER.warn("Unable to load system tray icon");
-			return;
-		}
+		this.trayIcon = new TrayIcon(Gui.loadImage("icons/qortal_ui_tray_synced.png"), "qortal", null);
 		// ...and attach mouse listener instead so we can use JPopupMenu (which does support Unicode)
 		this.trayIcon.addMouseListener(new MouseAdapter() {
 			@Override
@@ -184,6 +179,14 @@ public class SysTray {
 			menu.add(syncTime);
 		}
 
+		JMenuItem about = new JMenuItem(Translator.INSTANCE.translate("SysTray", "BUILD_VERSION"));
+		about.addActionListener(actionEvent -> {
+			destroyHiddenDialog();
+
+			JOptionPane.showMessageDialog(null,"Qortal Core\n" + Translator.INSTANCE.translate("SysTray", "BUILD_VERSION") + ":\n" + Controller.getInstance().getVersionStringWithoutPrefix(),"Qortal Core",1);
+		});
+		menu.add(about);
+
 		JMenuItem exit = new JMenuItem(Translator.INSTANCE.translate("SysTray", "EXIT"));
 		exit.addActionListener(actionEvent -> {
 			destroyHiddenDialog();

src/main/java/org/qortal/naming/Name.java

@@ -195,7 +195,7 @@ public class Name {
 		this.repository.getNameRepository().save(this.nameData);
 	}
 
-	public void buy(BuyNameTransactionData buyNameTransactionData) throws DataException {
+	public void buy(BuyNameTransactionData buyNameTransactionData, boolean modifyBalances) throws DataException {
 		// Save previous name-changing reference in this transaction's data
 		// Caller is expected to save
 		buyNameTransactionData.setNameReference(this.nameData.getReference());
@@ -203,15 +203,20 @@ public class Name {
 		// Mark not for-sale but leave price in case we want to orphan
 		this.nameData.setIsForSale(false);
 
-		// Update seller's balance
-		Account seller = new Account(this.repository, this.nameData.getOwner());
-		seller.modifyAssetBalance(Asset.QORT, buyNameTransactionData.getAmount());
+		if (modifyBalances) {
+			// Update seller's balance
+			Account seller = new Account(this.repository, this.nameData.getOwner());
+			seller.modifyAssetBalance(Asset.QORT, buyNameTransactionData.getAmount());
+		}
 
 		// Set new owner
 		Account buyer = new PublicKeyAccount(this.repository, buyNameTransactionData.getBuyerPublicKey());
 		this.nameData.setOwner(buyer.getAddress());
-		// Update buyer's balance
-		buyer.modifyAssetBalance(Asset.QORT, - buyNameTransactionData.getAmount());
+
+		if (modifyBalances) {
+			// Update buyer's balance
+			buyer.modifyAssetBalance(Asset.QORT, -buyNameTransactionData.getAmount());
+		}
 
 		// Set name-changing reference to this transaction
 		this.nameData.setReference(buyNameTransactionData.getSignature());

src/main/java/org/qortal/network/Handshake.java

@@ -13,7 +13,7 @@ import org.qortal.crypto.MemoryPoW;
 import org.qortal.network.message.ChallengeMessage;
 import org.qortal.network.message.HelloMessage;
 import org.qortal.network.message.Message;
-import org.qortal.network.message.Message.MessageType;
+import org.qortal.network.message.MessageType;
 import org.qortal.settings.Settings;
 import org.qortal.network.message.ResponseMessage;
 import org.qortal.utils.DaemonThreadFactory;

src/main/java/org/qortal/network/Network.java

@@ -8,11 +8,14 @@ import org.bouncycastle.crypto.params.Ed25519PublicKeyParameters;
 import org.qortal.block.BlockChain;
 import org.qortal.controller.Controller;
 import org.qortal.controller.arbitrary.ArbitraryDataFileListManager;
+import org.qortal.controller.arbitrary.ArbitraryDataManager;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.block.BlockData;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.network.PeerData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.network.message.*;
+import org.qortal.network.task.*;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
@@ -32,6 +35,7 @@ import java.nio.channels.*;
 import java.security.SecureRandom;
 import java.util.*;
 import java.util.concurrent.*;
+import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Function;
@@ -41,9 +45,8 @@ import java.util.stream.Collectors;
 // For managing peers
 public class Network {
     private static final Logger LOGGER = LogManager.getLogger(Network.class);
-    private static Network instance;
 
-    private static final int LISTEN_BACKLOG = 10;
+    private static final int LISTEN_BACKLOG = 5;
     /**
      * How long before retrying after a connection failure, in milliseconds.
      */
@@ -88,6 +91,8 @@ public class Network {
 
     private static final long DISCONNECTION_CHECK_INTERVAL = 10 * 1000L; // milliseconds
 
+    private static final int BROADCAST_CHAIN_TIP_DEPTH = 7; // Just enough to fill a SINGLE TCP packet (~1440 bytes)
+
     // Generate our node keys / ID
     private final Ed25519PrivateKeyParameters edPrivateKeyParams = new Ed25519PrivateKeyParameters(new SecureRandom());
     private final Ed25519PublicKeyParameters edPublicKeyParams = edPrivateKeyParams.generatePublicKey();
@@ -122,14 +127,8 @@ public class Network {
     private final ExecuteProduceConsume networkEPC;
     private Selector channelSelector;
     private ServerSocketChannel serverChannel;
-    private Iterator<SelectionKey> channelIterator = null;
-
-    // volatile because value is updated inside any one of the EPC threads
-    private volatile long nextConnectTaskTimestamp = 0L; // ms - try first connect once NTP syncs
-
-    private final ExecutorService broadcastExecutor = Executors.newCachedThreadPool();
-    // volatile because value is updated inside any one of the EPC threads
-    private volatile long nextBroadcastTimestamp = 0L; // ms - try first broadcast once NTP syncs
+    private SelectionKey serverSelectionKey;
+    private final Set<SelectableChannel> channelsPendingWrite = ConcurrentHashMap.newKeySet();
 
     private final Lock mergePeersLock = new ReentrantLock();
 
@@ -137,6 +136,8 @@ public class Network {
     private String ourExternalIpAddress = null;
     private int ourExternalPort = Settings.getInstance().getListenPort();
 
+    private volatile boolean isShuttingDown = false;
+
     // Constructors
 
     private Network() {
@@ -170,7 +171,7 @@ public class Network {
             serverChannel.configureBlocking(false);
             serverChannel.setOption(StandardSocketOptions.SO_REUSEADDR, true);
             serverChannel.bind(endpoint, LISTEN_BACKLOG);
-            serverChannel.register(channelSelector, SelectionKey.OP_ACCEPT);
+            serverSelectionKey = serverChannel.register(channelSelector, SelectionKey.OP_ACCEPT);
         } catch (UnknownHostException e) {
             LOGGER.error("Can't bind listen socket to address {}", Settings.getInstance().getBindAddress());
             throw new IOException("Can't bind listen socket to address", e);
@@ -180,7 +181,8 @@ public class Network {
         }
 
         // Load all known peers from repository
-        synchronized (this.allKnownPeers) { List<String> fixedNetwork = Settings.getInstance().getFixedNetwork();
+        synchronized (this.allKnownPeers) {
+            List<String> fixedNetwork = Settings.getInstance().getFixedNetwork();
             if (fixedNetwork != null && !fixedNetwork.isEmpty()) {
                 Long addedWhen = NTP.getTime();
                 String addedBy = "fixedNetwork";
@@ -214,12 +216,16 @@ public class Network {
 
     // Getters / setters
 
-    public static synchronized Network getInstance() {
-        if (instance == null) {
-            instance = new Network();
-        }
+    private static class SingletonContainer {
+        private static final Network INSTANCE = new Network();
+    }
 
-        return instance;
+    public static Network getInstance() {
+        return SingletonContainer.INSTANCE;
+    }
+
+    public int getMaxPeers() {
+        return this.maxPeers;
     }
 
     public byte[] getMessageMagic() {
@@ -257,6 +263,18 @@ public class Network {
         return this.immutableConnectedPeers;
     }
 
+    public List<Peer> getImmutableConnectedDataPeers() {
+        return this.getImmutableConnectedPeers().stream()
+                .filter(p -> p.isDataPeer())
+                .collect(Collectors.toList());
+    }
+
+    public List<Peer> getImmutableConnectedNonDataPeers() {
+        return this.getImmutableConnectedPeers().stream()
+                .filter(p -> !p.isDataPeer())
+                .collect(Collectors.toList());
+    }
+
     public void addConnectedPeer(Peer peer) {
         this.connectedPeers.add(peer); // thread safe thanks to synchronized list
         this.immutableConnectedPeers = List.copyOf(this.connectedPeers); // also thread safe thanks to synchronized collection's toArray() being fed to List.of(array)
@@ -323,6 +341,7 @@ public class Network {
                         // Add this signature to the list of pending requests for this peer
                         LOGGER.info("Making connection to peer {} to request files for signature {}...", peerAddressString, Base58.encode(signature));
                         Peer peer = new Peer(peerData);
+                        peer.setIsDataPeer(true);
                         peer.addPendingSignatureRequest(signature);
                         return this.connectPeer(peer);
                         // If connection (and handshake) is successful, data will automatically be requested
@@ -453,6 +472,13 @@ public class Network {
 
     class NetworkProcessor extends ExecuteProduceConsume {
 
+        private final Logger LOGGER = LogManager.getLogger(NetworkProcessor.class);
+
+        private final AtomicLong nextConnectTaskTimestamp = new AtomicLong(0L); // ms - try first connect once NTP syncs
+        private final AtomicLong nextBroadcastTimestamp = new AtomicLong(0L); // ms - try first broadcast once NTP syncs
+
+        private Iterator<SelectionKey> channelIterator = null;
+
         NetworkProcessor(ExecutorService executor) {
             super(executor);
         }
@@ -494,43 +520,23 @@ public class Network {
         }
 
         private Task maybeProducePeerMessageTask() {
-            for (Peer peer : getImmutableConnectedPeers()) {
-                Task peerTask = peer.getMessageTask();
-                if (peerTask != null) {
-                    return peerTask;
-                }
-            }
-
-            return null;
+            return getImmutableConnectedPeers().stream()
+                    .map(Peer::getMessageTask)
+                    .filter(Objects::nonNull)
+                    .findFirst()
+                    .orElse(null);
         }
 
         private Task maybeProducePeerPingTask(Long now) {
-            // Ask connected peers whether they need a ping
-            for (Peer peer : getImmutableHandshakedPeers()) {
-                Task peerTask = peer.getPingTask(now);
-                if (peerTask != null) {
-                    return peerTask;
-                }
-            }
-
-            return null;
-        }
-
-        class PeerConnectTask implements ExecuteProduceConsume.Task {
-            private final Peer peer;
-
-            PeerConnectTask(Peer peer) {
-                this.peer = peer;
-            }
-
-            @Override
-            public void perform() throws InterruptedException {
-                connectPeer(peer);
-            }
+            return getImmutableHandshakedPeers().stream()
+                    .map(peer -> peer.getPingTask(now))
+                    .filter(Objects::nonNull)
+                    .findFirst()
+                    .orElse(null);
         }
 
         private Task maybeProduceConnectPeerTask(Long now) throws InterruptedException {
-            if (now == null || now < nextConnectTaskTimestamp) {
+            if (now == null || now < nextConnectTaskTimestamp.get()) {
                 return null;
             }
 
@@ -538,7 +544,7 @@ public class Network {
                 return null;
             }
 
-            nextConnectTaskTimestamp = now + 1000L;
+            nextConnectTaskTimestamp.set(now + 1000L);
 
             Peer targetPeer = getConnectablePeer(now);
             if (targetPeer == null) {
@@ -550,66 +556,15 @@ public class Network {
         }
 
         private Task maybeProduceBroadcastTask(Long now) {
-            if (now == null || now < nextBroadcastTimestamp) {
+            if (now == null || now < nextBroadcastTimestamp.get()) {
                 return null;
             }
 
-            nextBroadcastTimestamp = now + BROADCAST_INTERVAL;
-            return () -> Controller.getInstance().doNetworkBroadcast();
-        }
-
-        class ChannelTask implements ExecuteProduceConsume.Task {
-            private final SelectionKey selectionKey;
-
-            ChannelTask(SelectionKey selectionKey) {
-                this.selectionKey = selectionKey;
-            }
-
-            @Override
-            public void perform() throws InterruptedException {
-                try {
-                    LOGGER.trace("Thread {} has pending channel: {}, with ops {}",
-                            Thread.currentThread().getId(), selectionKey.channel(), selectionKey.readyOps());
-
-                    // process pending channel task
-                    if (selectionKey.isReadable()) {
-                        connectionRead((SocketChannel) selectionKey.channel());
-                    } else if (selectionKey.isAcceptable()) {
-                        acceptConnection((ServerSocketChannel) selectionKey.channel());
-                    }
-
-                    LOGGER.trace("Thread {} processed channel: {}",
-                            Thread.currentThread().getId(), selectionKey.channel());
-                } catch (CancelledKeyException e) {
-                    LOGGER.trace("Thread {} encountered cancelled channel: {}",
-                            Thread.currentThread().getId(), selectionKey.channel());
-                }
-            }
-
-            private void connectionRead(SocketChannel socketChannel) {
-                Peer peer = getPeerFromChannel(socketChannel);
-                if (peer == null) {
-                    return;
-                }
-
-                try {
-                    peer.readChannel();
-                } catch (IOException e) {
-                    if (e.getMessage() != null && e.getMessage().toLowerCase().contains("connection reset")) {
-                        peer.disconnect("Connection reset");
-                        return;
-                    }
-
-                    LOGGER.trace("[{}] Network thread {} encountered I/O error: {}", peer.getPeerConnectionId(),
-                            Thread.currentThread().getId(), e.getMessage(), e);
-                    peer.disconnect("I/O error");
-                }
-            }
+            nextBroadcastTimestamp.set(now + BROADCAST_INTERVAL);
+            return new BroadcastTask();
         }
 
         private Task maybeProduceChannelTask(boolean canBlock) throws InterruptedException {
-            final SelectionKey nextSelectionKey;
-
             // Synchronization here to enforce thread-safety on channelIterator
             synchronized (channelSelector) {
                 // anything to do?
@@ -630,91 +585,73 @@ public class Network {
                     }
 
                     channelIterator = channelSelector.selectedKeys().iterator();
+                    LOGGER.trace("Thread {}, after {} select, channelIterator now {}",
+                            Thread.currentThread().getId(),
+                            canBlock ? "blocking": "non-blocking",
+                            channelIterator);
                 }
 
-                if (channelIterator.hasNext()) {
-                    nextSelectionKey = channelIterator.next();
-                    channelIterator.remove();
-                } else {
-                    nextSelectionKey = null;
+                if (!channelIterator.hasNext()) {
                     channelIterator = null; // Nothing to do so reset iterator to cause new select
+
+                    LOGGER.trace("Thread {}, channelIterator now null", Thread.currentThread().getId());
+                    return null;
                 }
 
-                LOGGER.trace("Thread {}, nextSelectionKey {}, channelIterator now {}",
-                        Thread.currentThread().getId(), nextSelectionKey, channelIterator);
-            }
+                final SelectionKey nextSelectionKey = channelIterator.next();
+                channelIterator.remove();
 
-            if (nextSelectionKey == null) {
-                return null;
-            }
+                // Just in case underlying socket channel already closed elsewhere, etc.
+                if (!nextSelectionKey.isValid())
+                    return null;
 
-            return new ChannelTask(nextSelectionKey);
-        }
-    }
+                LOGGER.trace("Thread {}, nextSelectionKey {}", Thread.currentThread().getId(), nextSelectionKey);
 
-    private void acceptConnection(ServerSocketChannel serverSocketChannel) throws InterruptedException {
-        SocketChannel socketChannel;
+                SelectableChannel socketChannel = nextSelectionKey.channel();
 
-        try {
-            socketChannel = serverSocketChannel.accept();
-        } catch (IOException e) {
-            return;
-        }
-
-        // No connection actually accepted?
-        if (socketChannel == null) {
-            return;
-        }
-        PeerAddress address = PeerAddress.fromSocket(socketChannel.socket());
-        List<String> fixedNetwork = Settings.getInstance().getFixedNetwork();
-        if (fixedNetwork != null && !fixedNetwork.isEmpty() && ipNotInFixedList(address, fixedNetwork)) {
-            try {
-                LOGGER.debug("Connection discarded from peer {} as not in the fixed network list", address);
-                socketChannel.close();
-            } catch (IOException e) {
-                // IGNORE
-            }
-            return;
-        }
-
-        final Long now = NTP.getTime();
-        Peer newPeer;
-
-        try {
-            if (now == null) {
-                LOGGER.debug("Connection discarded from peer {} due to lack of NTP sync", address);
-                socketChannel.close();
-                return;
-            }
-
-            if (getImmutableConnectedPeers().size() >= maxPeers) {
-                // We have enough peers
-                LOGGER.debug("Connection discarded from peer {} because the server is full", address);
-                socketChannel.close();
-                return;
-            }
-
-            LOGGER.debug("Connection accepted from peer {}", address);
-
-            newPeer = new Peer(socketChannel, channelSelector);
-            this.addConnectedPeer(newPeer);
-
-        } catch (IOException e) {
-            if (socketChannel.isOpen()) {
                 try {
-                    LOGGER.debug("Connection failed from peer {} while connecting/closing", address);
-                    socketChannel.close();
-                } catch (IOException ce) {
-                    // Couldn't close?
+                    if (nextSelectionKey.isReadable()) {
+                        clearInterestOps(nextSelectionKey, SelectionKey.OP_READ);
+                        Peer peer = getPeerFromChannel((SocketChannel) socketChannel);
+                        if (peer == null)
+                            return null;
+
+                        return new ChannelReadTask((SocketChannel) socketChannel, peer);
+                    }
+
+                    if (nextSelectionKey.isWritable()) {
+                        clearInterestOps(nextSelectionKey, SelectionKey.OP_WRITE);
+                        Peer peer = getPeerFromChannel((SocketChannel) socketChannel);
+                        if (peer == null)
+                            return null;
+
+                        // Any thread that queues a message to send can set OP_WRITE,
+                        // but we only allow one pending/active ChannelWriteTask per Peer
+                        if (!channelsPendingWrite.add(socketChannel))
+                            return null;
+
+                        return new ChannelWriteTask((SocketChannel) socketChannel, peer);
+                    }
+
+                    if (nextSelectionKey.isAcceptable()) {
+                        clearInterestOps(nextSelectionKey, SelectionKey.OP_ACCEPT);
+                        return new ChannelAcceptTask((ServerSocketChannel) socketChannel);
+                    }
+                } catch (CancelledKeyException e) {
+                    /*
+                     * Sometimes nextSelectionKey is cancelled / becomes invalid between the isValid() test at line 586
+                     * and later calls to isReadable() / isWritable() / isAcceptable() which themselves call isValid()!
+                     * Those isXXXable() calls could throw CancelledKeyException, so we catch it here and return null.
+                     */
+                    return null;
                 }
             }
-            return;
-        }
 
-        this.onPeerReady(newPeer);
+            return null;
+        }
     }
 
-    private boolean ipNotInFixedList(PeerAddress address, List<String> fixedNetwork) {
+    public boolean ipNotInFixedList(PeerAddress address, List<String> fixedNetwork) {
         for (String ipAddress : fixedNetwork) {
             String[] bits = ipAddress.split(":");
             if (bits.length >= 1 && bits.length <= 2 && address.getHost().equals(bits[0])) {
@@ -750,8 +687,9 @@ public class Network {
             peers.removeIf(isConnectedPeer);
 
             // Don't consider already connected peers (resolved address match)
-            // XXX This might be too slow if we end up waiting a long time for hostnames to resolve via DNS
-            peers.removeIf(isResolvedAsConnectedPeer);
+            // Disabled because this might be too slow if we end up waiting a long time for hostnames to resolve via DNS
+            // Which is ok because duplicate connections to the same peer are handled during handshaking
+            // peers.removeIf(isResolvedAsConnectedPeer);
 
             this.checkLongestConnection(now);
 
@@ -766,6 +704,7 @@ public class Network {
             // Pick candidate
             PeerData peerData = peers.get(peerIndex);
             Peer newPeer = new Peer(peerData);
+            newPeer.setIsDataPeer(false);
 
             // Update connection attempt info
             peerData.setLastAttempted(now);
@@ -781,8 +720,12 @@ public class Network {
         }
     }
 
-    private boolean connectPeer(Peer newPeer) throws InterruptedException {
-        SocketChannel socketChannel = newPeer.connect(this.channelSelector);
+    public boolean connectPeer(Peer newPeer) throws InterruptedException {
+        // Also checked before creating PeerConnectTask
+        if (getImmutableOutboundHandshakedPeers().size() >= minOutboundPeers)
+            return false;
+
+        SocketChannel socketChannel = newPeer.connect();
         if (socketChannel == null) {
             return false;
         }
@@ -797,7 +740,7 @@ public class Network {
         return true;
     }
 
-    private Peer getPeerFromChannel(SocketChannel socketChannel) {
+    public Peer getPeerFromChannel(SocketChannel socketChannel) {
         for (Peer peer : this.getImmutableConnectedPeers()) {
             if (peer.getSocketChannel() == socketChannel) {
                 return peer;
@@ -830,7 +773,74 @@ public class Network {
         nextDisconnectionCheck = now + DISCONNECTION_CHECK_INTERVAL;
     }
 
-    // Peer callbacks
+    // SocketChannel interest-ops manipulations
+
+    private static final String[] OP_NAMES = new String[SelectionKey.OP_ACCEPT * 2];
+    static {
+        for (int i = 0; i < OP_NAMES.length; i++) {
+            StringJoiner joiner = new StringJoiner(",");
+
+            if ((i & SelectionKey.OP_READ) != 0) joiner.add("OP_READ");
+            if ((i & SelectionKey.OP_WRITE) != 0) joiner.add("OP_WRITE");
+            if ((i & SelectionKey.OP_CONNECT) != 0) joiner.add("OP_CONNECT");
+            if ((i & SelectionKey.OP_ACCEPT) != 0) joiner.add("OP_ACCEPT");
+
+            OP_NAMES[i] = joiner.toString();
+        }
+    }
+
+    public void clearInterestOps(SelectableChannel socketChannel, int interestOps) {
+        SelectionKey selectionKey = socketChannel.keyFor(channelSelector);
+        if (selectionKey == null)
+            return;
+
+        clearInterestOps(selectionKey, interestOps);
+    }
+
+    private void clearInterestOps(SelectionKey selectionKey, int interestOps) {
+        if (!selectionKey.channel().isOpen())
+            return;
+
+        LOGGER.trace("Thread {} clearing {} interest-ops on channel: {}",
+                Thread.currentThread().getId(),
+                OP_NAMES[interestOps],
+                selectionKey.channel());
+
+        selectionKey.interestOpsAnd(~interestOps);
+    }
+
+    public void setInterestOps(SelectableChannel socketChannel, int interestOps) {
+        SelectionKey selectionKey = socketChannel.keyFor(channelSelector);
+        if (selectionKey == null) {
+            try {
+                selectionKey = socketChannel.register(this.channelSelector, interestOps);
+            } catch (ClosedChannelException e) {
+                // Channel already closed so ignore
+                return;
+            }
+            // Fall-through to allow logging
+        }
+
+        setInterestOps(selectionKey, interestOps);
+    }
+
+    private void setInterestOps(SelectionKey selectionKey, int interestOps) {
+        if (!selectionKey.channel().isOpen())
+            return;
+
+        LOGGER.trace("Thread {} setting {} interest-ops on channel: {}",
+                Thread.currentThread().getId(),
+                OP_NAMES[interestOps],
+                selectionKey.channel());
+
+        selectionKey.interestOpsOr(interestOps);
+    }
+
+    // Peer / Task callbacks
+
+    public void notifyChannelNotWriting(SelectableChannel socketChannel) {
+        this.channelsPendingWrite.remove(socketChannel);
+    }
 
     protected void wakeupChannelSelector() {
         this.channelSelector.wakeup();
@@ -856,8 +866,6 @@ public class Network {
     }
 
     public void onDisconnect(Peer peer) {
-        // Notify Controller
-        Controller.getInstance().onPeerDisconnect(peer);
         if (peer.getConnectionEstablishedTime() > 0L) {
             LOGGER.debug("[{}] Disconnected from peer {}", peer.getPeerConnectionId(), peer);
         } else {
@@ -865,6 +873,25 @@ public class Network {
         }
 
         this.removeConnectedPeer(peer);
+        this.channelsPendingWrite.remove(peer.getSocketChannel());
+
+        if (this.isShuttingDown)
+            // No need to do any further processing, like re-enabling listen socket or notifying Controller
+            return;
+
+        if (getImmutableConnectedPeers().size() < maxPeers - 1
+                && serverSelectionKey.isValid()
+                && (serverSelectionKey.interestOps() & SelectionKey.OP_ACCEPT) == 0) {
+            try {
+                LOGGER.debug("Re-enabling accepting incoming connections because the server is not longer full");
+                setInterestOps(serverSelectionKey, SelectionKey.OP_ACCEPT);
+            } catch (CancelledKeyException e) {
+                LOGGER.error("Failed to re-enable accepting of incoming connections: {}", e.getMessage());
+            }
+        }
+
+        // Notify Controller
+        Controller.getInstance().onPeerDisconnect(peer);
     }
 
     public void peerMisbehaved(Peer peer) {
@@ -1062,11 +1089,19 @@ public class Network {
         // (If inbound sent anything here, it's possible it could be processed out-of-order with handshake message).
 
         if (peer.isOutbound()) {
-            // Send our height
-            Message heightMessage = buildHeightMessage(peer, Controller.getInstance().getChainTip());
-            if (!peer.sendMessage(heightMessage)) {
-                peer.disconnect("failed to send height/info");
-                return;
+            if (!Settings.getInstance().isLite()) {
+                // Send our height / chain tip info
+                Message message = this.buildHeightOrChainTipInfo(peer);
+
+                if (message == null) {
+                    peer.disconnect("Couldn't build our chain tip info");
+                    return;
+                }
+
+                if (!peer.sendMessage(message)) {
+                    peer.disconnect("failed to send height / chain tip info");
+                    return;
+                }
             }
 
             // Send our peers list
@@ -1138,10 +1173,47 @@ public class Network {
         return new PeersV2Message(peerAddresses);
     }
 
-    public Message buildHeightMessage(Peer peer, BlockData blockData) {
-        // HEIGHT_V2 contains way more useful info
-        return new HeightV2Message(blockData.getHeight(), blockData.getSignature(),
-                blockData.getTimestamp(), blockData.getMinterPublicKey());
+    /** Builds either (legacy) HeightV2Message or (newer) BlockSummariesV2Message, depending on peer version.
+     *
+     *  @return Message, or null if DataException was thrown.
+     */
+    public Message buildHeightOrChainTipInfo(Peer peer) {
+        if (peer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION) {
+            int latestHeight = Controller.getInstance().getChainHeight();
+
+            try (final Repository repository = RepositoryManager.getRepository()) {
+                List<BlockSummaryData> latestBlockSummaries = repository.getBlockRepository().getBlockSummaries(latestHeight - BROADCAST_CHAIN_TIP_DEPTH, latestHeight);
+                return new BlockSummariesV2Message(latestBlockSummaries);
+            } catch (DataException e) {
+                return null;
+            }
+        } else {
+            // For older peers
+            BlockData latestBlockData = Controller.getInstance().getChainTip();
+            return new HeightV2Message(latestBlockData.getHeight(), latestBlockData.getSignature(),
+                    latestBlockData.getTimestamp(), latestBlockData.getMinterPublicKey());
+        }
+    }
+
+    public void broadcastOurChain() {
+        BlockData latestBlockData = Controller.getInstance().getChainTip();
+        int latestHeight = latestBlockData.getHeight();
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            List<BlockSummaryData> latestBlockSummaries = repository.getBlockRepository().getBlockSummaries(latestHeight - BROADCAST_CHAIN_TIP_DEPTH, latestHeight);
+            Message latestBlockSummariesMessage = new BlockSummariesV2Message(latestBlockSummaries);
+
+            // For older peers
+            Message heightMessage = new HeightV2Message(latestBlockData.getHeight(), latestBlockData.getSignature(),
+                    latestBlockData.getTimestamp(), latestBlockData.getMinterPublicKey());
+
+            Network.getInstance().broadcast(broadcastPeer -> broadcastPeer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION
+                    ? latestBlockSummariesMessage
+                    : heightMessage
+            );
+        } catch (DataException e) {
+            LOGGER.warn("Couldn't broadcast our chain tip info", e);
+        }
     }
 
     public Message buildNewTransactionMessage(Peer peer, TransactionData transactionData) {
@@ -1302,8 +1374,9 @@ public class Network {
         try {
             InetSocketAddress knownAddress = peerAddress.toSocketAddress();
 
-            List<Peer> peers = this.getImmutableConnectedPeers();
-            peers.removeIf(peer -> !Peer.addressEquals(knownAddress, peer.getResolvedAddress()));
+            List<Peer> peers = this.getImmutableConnectedPeers().stream()
+                    .filter(peer -> Peer.addressEquals(knownAddress, peer.getResolvedAddress()))
+                    .collect(Collectors.toList());
 
             for (Peer peer : peers) {
                 peer.disconnect("to be forgotten");
@@ -1461,54 +1534,27 @@ public class Network {
     }
 
     public void broadcast(Function<Peer, Message> peerMessageBuilder) {
-        class Broadcaster implements Runnable {
-            private final Random random = new Random();
+        for (Peer peer : getImmutableHandshakedPeers()) {
+            if (this.isShuttingDown)
+                return;
 
-            private List<Peer> targetPeers;
-            private Function<Peer, Message> peerMessageBuilder;
+            Message message = peerMessageBuilder.apply(peer);
 
-            Broadcaster(List<Peer> targetPeers, Function<Peer, Message> peerMessageBuilder) {
-                this.targetPeers = targetPeers;
-                this.peerMessageBuilder = peerMessageBuilder;
+            if (message == null) {
+                continue;
             }
 
-            @Override
-            public void run() {
-                Thread.currentThread().setName("Network Broadcast");
-
-                for (Peer peer : targetPeers) {
-                    // Very short sleep to reduce strain, improve multi-threading and catch interrupts
-                    try {
-                        Thread.sleep(random.nextInt(20) + 20L);
-                    } catch (InterruptedException e) {
-                        break;
-                    }
-
-                    Message message = peerMessageBuilder.apply(peer);
-
-                    if (message == null) {
-                        continue;
-                    }
-
-                    if (!peer.sendMessage(message)) {
-                        peer.disconnect("failed to broadcast message");
-                    }
-                }
-
-                Thread.currentThread().setName("Network Broadcast (dormant)");
+            if (!peer.sendMessage(message)) {
+                peer.disconnect("failed to broadcast message");
             }
         }
-
-        try {
-            broadcastExecutor.execute(new Broadcaster(this.getImmutableHandshakedPeers(), peerMessageBuilder));
-        } catch (RejectedExecutionException e) {
-            // Can't execute - probably because we're shutting down, so ignore
-        }
     }
 
     // Shutdown
 
     public void shutdown() {
+        this.isShuttingDown = true;
+
         // Close listen socket to prevent more incoming connections
         if (this.serverChannel.isOpen()) {
             try {
@@ -1527,16 +1573,6 @@ public class Network {
             LOGGER.warn("Interrupted while waiting for networking threads to terminate");
         }
 
-        // Stop broadcasts
-        this.broadcastExecutor.shutdownNow();
-        try {
-            if (!this.broadcastExecutor.awaitTermination(1000, TimeUnit.MILLISECONDS)) {
-                LOGGER.warn("Broadcast threads failed to terminate");
-            }
-        } catch (InterruptedException e) {
-            LOGGER.warn("Interrupted while waiting for broadcast threads failed to terminate");
-        }
-
         // Close all peer connections
         for (Peer peer : this.getImmutableConnectedPeers()) {
             peer.shutdown();

src/main/java/org/qortal/network/Peer.java

@@ -6,30 +6,29 @@ import com.google.common.net.InetAddresses;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.controller.Controller;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.block.CommonBlockData;
-import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.network.PeerData;
 import org.qortal.network.message.ChallengeMessage;
 import org.qortal.network.message.Message;
-import org.qortal.network.message.Message.MessageException;
-import org.qortal.network.message.Message.MessageType;
-import org.qortal.network.message.PingMessage;
+import org.qortal.network.message.MessageException;
+import org.qortal.network.message.MessageType;
+import org.qortal.network.task.MessageTask;
+import org.qortal.network.task.PingTask;
 import org.qortal.settings.Settings;
-import org.qortal.utils.ExecuteProduceConsume;
+import org.qortal.utils.ExecuteProduceConsume.Task;
 import org.qortal.utils.NTP;
 
 import java.io.IOException;
 import java.net.*;
 import java.nio.ByteBuffer;
 import java.nio.channels.SelectionKey;
-import java.nio.channels.Selector;
 import java.nio.channels.SocketChannel;
 import java.security.SecureRandom;
 import java.util.*;
-import java.util.concurrent.ArrayBlockingQueue;
-import java.util.concurrent.BlockingQueue;
-import java.util.concurrent.LinkedBlockingQueue;
-import java.util.concurrent.TimeUnit;
+import java.util.concurrent.*;
+import java.util.concurrent.atomic.LongAccumulator;
+import java.util.concurrent.atomic.LongAdder;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -48,9 +47,9 @@ public class Peer {
     private static final int RESPONSE_TIMEOUT = 3000; // ms
 
     /**
-     * Maximum time to wait for a peer to respond with blocks (ms)
+     * Maximum time to wait for a message to be added to sendQueue (ms)
      */
-    public static final int FETCH_BLOCKS_TIMEOUT = 10000;
+    private static final int QUEUE_TIMEOUT = 1000; // ms
 
     /**
      * Interval between PING messages to a peer. (ms)
@@ -68,13 +67,22 @@ public class Peer {
      */
     private boolean isLocal;
 
+    /**
+     * True if connected for the purposes of transfering specific QDN data
+     */
+    private boolean isDataPeer;
+
     private final UUID peerConnectionId = UUID.randomUUID();
     private final Object byteBufferLock = new Object();
     private ByteBuffer byteBuffer;
-
     private Map<Integer, BlockingQueue<Message>> replyQueues;
     private LinkedBlockingQueue<Message> pendingMessages;
 
+    private TransferQueue<Message> sendQueue;
+    private ByteBuffer outputBuffer;
+    private String outputMessageType;
+    private int outputMessageId;
+
     /**
      * True if we created connection to peer, false if we accepted incoming connection from peer.
      */
@@ -98,7 +106,7 @@ public class Peer {
     /**
      * When last PING message was sent, or null if pings not started yet.
      */
-    private Long lastPingSent;
+    private Long lastPingSent = null;
 
     byte[] ourChallenge;
 
@@ -140,13 +148,23 @@ public class Peer {
     /**
      * Latest block info as reported by peer.
      */
-    private PeerChainTipData peersChainTipData;
+    private List<BlockSummaryData> peersChainTipData = Collections.emptyList();
 
     /**
      * Our common block with this peer
      */
     private CommonBlockData commonBlockData;
 
+    // Message stats
+
+    private static class MessageStats {
+        public final LongAdder count = new LongAdder();
+        public final LongAdder totalBytes = new LongAdder();
+    }
+
+    private final Map<MessageType, MessageStats> receivedMessageStats = new ConcurrentHashMap<>();
+    private final Map<MessageType, MessageStats> sentMessageStats = new ConcurrentHashMap<>();
+
     // Constructors
 
     /**
@@ -160,10 +178,10 @@ public class Peer {
     /**
      * Construct Peer using existing, connected socket
      */
-    public Peer(SocketChannel socketChannel, Selector channelSelector) throws IOException {
+    public Peer(SocketChannel socketChannel) throws IOException {
         this.isOutbound = false;
         this.socketChannel = socketChannel;
-        sharedSetup(channelSelector);
+        sharedSetup();
 
         this.resolvedAddress = ((InetSocketAddress) socketChannel.socket().getRemoteSocketAddress());
         this.isLocal = isAddressLocal(this.resolvedAddress.getAddress());
@@ -194,6 +212,14 @@ public class Peer {
         return this.isOutbound;
     }
 
+    public boolean isDataPeer() {
+        return isDataPeer;
+    }
+
+    public void setIsDataPeer(boolean isDataPeer) {
+        this.isDataPeer = isDataPeer;
+    }
+
     public Handshake getHandshakeStatus() {
         synchronized (this.handshakingLock) {
             return this.handshakeStatus;
@@ -211,6 +237,11 @@ public class Peer {
     }
 
     private void generateRandomMaxConnectionAge() {
+        if (this.maxConnectionAge > 0L) {
+            // Already generated, so we don't want to overwrite the existing value
+            return;
+        }
+
         // Retrieve the min and max connection time from the settings, and calculate the range
         final int minPeerConnectionTime = Settings.getInstance().getMinPeerConnectionTime();
         final int maxPeerConnectionTime = Settings.getInstance().getMaxPeerConnectionTime();
@@ -276,7 +307,7 @@ public class Peer {
         }
     }
 
-    protected void setLastPing(long lastPing) {
+    public void setLastPing(long lastPing) {
         synchronized (this.peerInfoLock) {
             this.lastPing = lastPing;
         }
@@ -322,34 +353,34 @@ public class Peer {
         }
     }
 
-    public PeerChainTipData getChainTipData() {
-        synchronized (this.peerInfoLock) {
-            return this.peersChainTipData;
-        }
+    public BlockSummaryData getChainTipData() {
+        List<BlockSummaryData> chainTipSummaries = this.peersChainTipData;
+
+        if (chainTipSummaries.isEmpty())
+            return null;
+
+        // Return last entry, which should have greatest height
+        return chainTipSummaries.get(chainTipSummaries.size() - 1);
     }
 
-    public void setChainTipData(PeerChainTipData chainTipData) {
-        synchronized (this.peerInfoLock) {
-            this.peersChainTipData = chainTipData;
-        }
+    public void setChainTipData(BlockSummaryData chainTipData) {
+        this.peersChainTipData = Collections.singletonList(chainTipData);
+    }
+
+    public List<BlockSummaryData> getChainTipSummaries() {
+        return this.peersChainTipData;
+    }
+
+    public void setChainTipSummaries(List<BlockSummaryData> chainTipSummaries) {
+        this.peersChainTipData = List.copyOf(chainTipSummaries);
     }
 
     public CommonBlockData getCommonBlockData() {
-        synchronized (this.peerInfoLock) {
-            return this.commonBlockData;
-        }
+        return this.commonBlockData;
     }
 
     public void setCommonBlockData(CommonBlockData commonBlockData) {
-        synchronized (this.peerInfoLock) {
-            this.commonBlockData = commonBlockData;
-        }
-    }
-
-    protected void queueMessage(Message message) {
-        if (!this.pendingMessages.offer(message)) {
-            LOGGER.info("[{}] No room to queue message from peer {} - discarding", this.peerConnectionId, this);
-        }
+        this.commonBlockData = commonBlockData;
     }
 
     public boolean isSyncInProgress() {
@@ -396,13 +427,14 @@ public class Peer {
 
     // Processing
 
-    private void sharedSetup(Selector channelSelector) throws IOException {
+    private void sharedSetup() throws IOException {
         this.connectionTimestamp = NTP.getTime();
         this.socketChannel.setOption(StandardSocketOptions.TCP_NODELAY, true);
         this.socketChannel.configureBlocking(false);
-        this.socketChannel.register(channelSelector, SelectionKey.OP_READ);
+        Network.getInstance().setInterestOps(this.socketChannel, SelectionKey.OP_READ);
         this.byteBuffer = null; // Defer allocation to when we need it, to save memory. Sorry GC!
-        this.replyQueues = Collections.synchronizedMap(new HashMap<Integer, BlockingQueue<Message>>());
+        this.sendQueue = new LinkedTransferQueue<>();
+        this.replyQueues = new ConcurrentHashMap<>();
         this.pendingMessages = new LinkedBlockingQueue<>();
 
         Random random = new SecureRandom();
@@ -410,7 +442,7 @@ public class Peer {
         random.nextBytes(this.ourChallenge);
     }
 
-    public SocketChannel connect(Selector channelSelector) {
+    public SocketChannel connect() {
         LOGGER.trace("[{}] Connecting to peer {}", this.peerConnectionId, this);
 
         try {
@@ -418,6 +450,8 @@ public class Peer {
             this.isLocal = isAddressLocal(this.resolvedAddress.getAddress());
 
             this.socketChannel = SocketChannel.open();
+            InetAddress bindAddr = InetAddress.getByName(Settings.getInstance().getBindAddress());
+            this.socketChannel.socket().bind(new InetSocketAddress(bindAddr, 0));
             this.socketChannel.socket().connect(resolvedAddress, CONNECT_TIMEOUT);
         } catch (SocketTimeoutException e) {
             LOGGER.trace("[{}] Connection timed out to peer {}", this.peerConnectionId, this);
@@ -432,7 +466,7 @@ public class Peer {
 
         try {
             LOGGER.debug("[{}] Connected to peer {}", this.peerConnectionId, this);
-            sharedSetup(channelSelector);
+            sharedSetup();
             return socketChannel;
         } catch (IOException e) {
             LOGGER.trace("[{}] Post-connection setup failed, peer {}", this.peerConnectionId, this);
@@ -450,7 +484,7 @@ public class Peer {
      *
      * @throws IOException If this channel is not yet connected
      */
-    protected void readChannel() throws IOException {
+    public void readChannel() throws IOException {
         synchronized (this.byteBufferLock) {
             while (true) {
                 if (!this.socketChannel.isOpen() || this.socketChannel.socket().isClosed()) {
@@ -526,11 +560,22 @@ public class Peer {
                     // Tidy up buffers:
                     this.byteBuffer.flip();
                     // Read-only, flipped buffer's position will be after end of message, so copy that
+                    long messageByteSize = readOnlyBuffer.position();
                     this.byteBuffer.position(readOnlyBuffer.position());
                     // Copy bytes after read message to front of buffer,
                     // adjusting position accordingly, reset limit to capacity
                     this.byteBuffer.compact();
 
+                    // Record message stats
+                    MessageStats messageStats = this.receivedMessageStats.computeIfAbsent(message.getType(), k -> new MessageStats());
+                    // Ideally these two operations would be atomic, we could pack 'count' in top X bits of the 64-bit long, but meh
+                    messageStats.count.increment();
+                    messageStats.totalBytes.add(messageByteSize);
+
+                    // Unsupported message type? Discard with no further processing
+                    if (message.getType() == MessageType.UNSUPPORTED)
+                        continue;
+
                     BlockingQueue<Message> queue = this.replyQueues.get(message.getId());
                     if (queue != null) {
                         // Adding message to queue will unblock thread waiting for response
@@ -556,7 +601,73 @@ public class Peer {
         }
     }
 
-    protected ExecuteProduceConsume.Task getMessageTask() {
+    /** Maybe send some pending outgoing messages.
+     *
+     * @return true if more data is pending to be sent
+     */
+    public boolean writeChannel() throws IOException {
+        // It is the responsibility of ChannelWriteTask's producer to produce only one call to writeChannel() at a time
+
+        while (true) {
+            // If output byte buffer is null, fetch next message from queue (if any)
+            while (this.outputBuffer == null) {
+                Message message;
+
+                try {
+                    // Allow other thread time to add message to queue having raised OP_WRITE.
+                    // Timeout is overkill but not excessive enough to clog up networking / EPC.
+                    // This is to avoid race condition in sendMessageWithTimeout() below.
+                    message = this.sendQueue.poll(QUEUE_TIMEOUT, TimeUnit.MILLISECONDS);
+                } catch (InterruptedException e) {
+                    // Shutdown situation
+                    return false;
+                }
+
+                // No message? No further work to be done
+                if (message == null)
+                    return false;
+
+                try {
+                    this.outputBuffer = ByteBuffer.wrap(message.toBytes());
+                    this.outputMessageType = message.getType().name();
+                    this.outputMessageId = message.getId();
+
+                    LOGGER.trace("[{}] Sending {} message with ID {} to peer {}",
+                            this.peerConnectionId, this.outputMessageType, this.outputMessageId, this);
+
+                    // Record message stats
+                    MessageStats messageStats = this.sentMessageStats.computeIfAbsent(message.getType(), k -> new MessageStats());
+                    // Ideally these two operations would be atomic, we could pack 'count' in top X bits of the 64-bit long, but meh
+                    messageStats.count.increment();
+                    messageStats.totalBytes.add(this.outputBuffer.limit());
+                } catch (MessageException e) {
+                    // Something went wrong converting message to bytes, so discard but allow another round
+                    LOGGER.warn("[{}] Failed to send {} message with ID {} to peer {}: {}", this.peerConnectionId,
+                            message.getType().name(), message.getId(), this, e.getMessage());
+                }
+            }
+
+            // If output byte buffer is not null, send from that
+            int bytesWritten = this.socketChannel.write(outputBuffer);
+
+            LOGGER.trace("[{}] Sent {} bytes of {} message with ID {} to peer {} ({} total)", this.peerConnectionId,
+                    bytesWritten, this.outputMessageType, this.outputMessageId, this, outputBuffer.limit());
+
+            // If we've sent 0 bytes then socket buffer is full so we need to wait until it's empty again
+            if (bytesWritten == 0) {
+                return true;
+            }
+
+            // If we then exhaust the byte buffer, set it to null (otherwise loop and try to send more)
+            if (!this.outputBuffer.hasRemaining()) {
+                this.outputMessageType = null;
+                this.outputMessageId = 0;
+                this.outputBuffer = null;
+            }
+        }
+    }
+
+    protected Task getMessageTask() {
         /*
          * If we are still handshaking and there is a message yet to be processed then
          * don't produce another message task. This allows us to process handshake
@@ -580,7 +691,7 @@ public class Peer {
         }
 
         // Return a task to process message in queue
-        return () -> Network.getInstance().onMessage(this, nextMessage);
+        return new MessageTask(this, nextMessage);
     }
 
     /**
@@ -605,54 +716,25 @@ public class Peer {
         }
 
         try {
-            // Send message
-            LOGGER.trace("[{}] Sending {} message with ID {} to peer {}", this.peerConnectionId,
+            // Queue message, to be picked up by ChannelWriteTask and then peer.writeChannel()
+            LOGGER.trace("[{}] Queuing {} message with ID {} to peer {}", this.peerConnectionId,
                     message.getType().name(), message.getId(), this);
 
-            ByteBuffer outputBuffer = ByteBuffer.wrap(message.toBytes());
+            // Check message properly constructed
+            message.checkValidOutgoing();
 
-            synchronized (this.socketChannel) {
-                final long sendStart = System.currentTimeMillis();
-                long totalBytes = 0;
-
-                while (outputBuffer.hasRemaining()) {
-                    int bytesWritten = this.socketChannel.write(outputBuffer);
-                    totalBytes += bytesWritten;
-
-                    LOGGER.trace("[{}] Sent {} bytes of {} message with ID {} to peer {} ({} total)", this.peerConnectionId,
-                            bytesWritten, message.getType().name(), message.getId(), this, totalBytes);
-
-                    if (bytesWritten == 0) {
-                        // Underlying socket's internal buffer probably full,
-                        // so wait a short while for bytes to actually be transmitted over the wire
-
-                        /*
-                         * NOSONAR squid:S2276 - we don't want to use this.socketChannel.wait()
-                         * as this releases the lock held by synchronized() above
-                         * and would allow another thread to send another message,
-                         * potentially interleaving them on-the-wire, causing checksum failures
-                         * and connection loss.
-                         */
-                        Thread.sleep(1L); //NOSONAR squid:S2276
-
-                        if (System.currentTimeMillis() - sendStart > timeout) {
-                            // We've taken too long to send this message
-                            return false;
-                        }
-                    }
-                }
-            }
-        } catch (MessageException e) {
-            LOGGER.warn("[{}] Failed to send {} message with ID {} to peer {}: {}", this.peerConnectionId,
-                    message.getType().name(), message.getId(), this, e.getMessage());
-            return false;
-        } catch (IOException | InterruptedException e) {
+            // Possible race condition:
+            // We set OP_WRITE, EPC creates ChannelWriteTask which calls Peer.writeChannel, writeChannel's poll() finds no message to send
+            // Avoided by poll-with-timeout in writeChannel() above.
+            Network.getInstance().setInterestOps(this.socketChannel, SelectionKey.OP_WRITE);
+            return this.sendQueue.tryTransfer(message, timeout, TimeUnit.MILLISECONDS);
+        } catch (InterruptedException e) {
             // Send failure
             return false;
+        } catch (MessageException e) {
+            LOGGER.error(e.getMessage(), e);
+            return false;
         }
-
-        // Sent OK
-        return true;
     }
 
     /**
@@ -720,7 +802,7 @@ public class Peer {
         this.lastPingSent = NTP.getTime();
     }
 
-    protected ExecuteProduceConsume.Task getPingTask(Long now) {
+    protected Task getPingTask(Long now) {
         // Pings not enabled yet?
         if (now == null || this.lastPingSent == null) {
             return null;
@@ -734,19 +816,7 @@ public class Peer {
         // Not strictly true, but prevents this peer from being immediately chosen again
         this.lastPingSent = now;
 
-        return () -> {
-            PingMessage pingMessage = new PingMessage();
-            Message message = this.getResponse(pingMessage);
-
-            if (message == null || message.getType() != MessageType.PING) {
-                LOGGER.debug("[{}] Didn't receive reply from {} for PING ID {}", this.peerConnectionId, this,
-                        pingMessage.getId());
-                this.disconnect("no ping received");
-                return;
-            }
-
-            this.setLastPing(NTP.getTime() - now);
-        };
+        return new PingTask(this, now);
     }
 
     public void disconnect(String reason) {
@@ -760,8 +830,11 @@ public class Peer {
     }
 
     public void shutdown() {
+        boolean logStats = false;
+
         if (!isStopping) {
             LOGGER.debug("[{}] Shutting down peer {}", this.peerConnectionId, this);
+            logStats = true;
         }
         isStopping = true;
 
@@ -773,8 +846,34 @@ public class Peer {
                 LOGGER.debug("[{}] IOException while trying to close peer {}", this.peerConnectionId, this);
             }
         }
+
+        if (logStats && this.receivedMessageStats.size() > 0) {
+            StringBuilder statsBuilder = new StringBuilder(1024);
+            statsBuilder.append("peer ").append(this).append(" message stats:\n=received=");
+            appendMessageStats(statsBuilder, this.receivedMessageStats);
+            statsBuilder.append("\n=sent=");
+            appendMessageStats(statsBuilder, this.sentMessageStats);
+
+            LOGGER.debug(statsBuilder.toString());
+        }
     }
 
+    private static void appendMessageStats(StringBuilder statsBuilder, Map<MessageType, MessageStats> messageStats) {
+        if (messageStats.isEmpty()) {
+            statsBuilder.append("\n  none");
+            return;
+        }
+
+        messageStats.keySet().stream()
+                .sorted(Comparator.comparing(MessageType::name))
+                .forEach(messageType -> {
+                    MessageStats stats = messageStats.get(messageType);
+
+                    statsBuilder.append("\n  ").append(messageType.name())
+                            .append(": count=").append(stats.count.sum())
+                            .append(", total bytes=").append(stats.totalBytes.sum());
+                });
+    }
 
     // Minimum version
 
@@ -811,20 +910,22 @@ public class Peer {
     // Common block data
 
     public boolean canUseCachedCommonBlockData() {
-        PeerChainTipData peerChainTipData = this.getChainTipData();
-        CommonBlockData commonBlockData = this.getCommonBlockData();
+        BlockSummaryData peerChainTipData = this.getChainTipData();
+        if (peerChainTipData == null || peerChainTipData.getSignature() == null)
+            return false;
 
-        if (peerChainTipData != null && commonBlockData != null) {
-            PeerChainTipData commonBlockChainTipData = commonBlockData.getChainTipData();
-            if (peerChainTipData.getLastBlockSignature() != null && commonBlockChainTipData != null
-                    && commonBlockChainTipData.getLastBlockSignature() != null) {
-                if (Arrays.equals(peerChainTipData.getLastBlockSignature(),
-                        commonBlockChainTipData.getLastBlockSignature())) {
-                    return true;
-                }
-            }
-        }
-        return false;
+        CommonBlockData commonBlockData = this.getCommonBlockData();
+        if (commonBlockData == null)
+            return false;
+
+        BlockSummaryData commonBlockChainTipData = commonBlockData.getChainTipData();
+        if (commonBlockChainTipData == null || commonBlockChainTipData.getSignature() == null)
+            return false;
+
+        if (!Arrays.equals(peerChainTipData.getSignature(), commonBlockChainTipData.getSignature()))
+            return false;
+
+        return true;
     }
 
 
@@ -877,6 +978,10 @@ public class Peer {
         return maxConnectionAge;
     }
 
+    public void setMaxConnectionAge(long maxConnectionAge) {
+        this.maxConnectionAge = maxConnectionAge;
+    }
+
     public boolean hasReachedMaxConnectionAge() {
         return this.getConnectionAge() > this.getMaxConnectionAge();
     }

src/main/java/org/qortal/network/message/AccountBalanceMessage.java

@@ -0,0 +1,70 @@
+package org.qortal.network.message;
+
+import com.google.common.primitives.Longs;
+import org.qortal.data.account.AccountBalanceData;
+import org.qortal.transform.Transformer;
+import org.qortal.utils.Base58;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+public class AccountBalanceMessage extends Message {
+
+	private static final int ADDRESS_LENGTH = Transformer.ADDRESS_LENGTH;
+
+	private AccountBalanceData accountBalanceData;
+
+	public AccountBalanceMessage(AccountBalanceData accountBalanceData) {
+		super(MessageType.ACCOUNT_BALANCE);
+
+		ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+		try {
+			// Send raw address instead of base58 encoded
+			byte[] address = Base58.decode(accountBalanceData.getAddress());
+			bytes.write(address);
+
+			bytes.write(Longs.toByteArray(accountBalanceData.getAssetId()));
+
+			bytes.write(Longs.toByteArray(accountBalanceData.getBalance()));
+
+		} catch (IOException e) {
+			throw new AssertionError("IOException shouldn't occur with ByteArrayOutputStream");
+		}
+
+		this.dataBytes = bytes.toByteArray();
+		this.checksumBytes = Message.generateChecksum(this.dataBytes);
+	}
+
+	public AccountBalanceMessage(int id, AccountBalanceData accountBalanceData) {
+		super(id, MessageType.ACCOUNT_BALANCE);
+
+		this.accountBalanceData = accountBalanceData;
+	}
+
+	public AccountBalanceData getAccountBalanceData() {
+		return this.accountBalanceData;
+	}
+
+
+	public static Message fromByteBuffer(int id, ByteBuffer byteBuffer) {
+		byte[] addressBytes = new byte[ADDRESS_LENGTH];
+		byteBuffer.get(addressBytes);
+		String address = Base58.encode(addressBytes);
+
+		long assetId = byteBuffer.getLong();
+
+		long balance = byteBuffer.getLong();
+
+		AccountBalanceData accountBalanceData = new AccountBalanceData(address, assetId, balance);
+		return new AccountBalanceMessage(id, accountBalanceData);
+	}
+
+	public AccountBalanceMessage cloneWithNewId(int newId) {
+		AccountBalanceMessage clone = new AccountBalanceMessage(this.accountBalanceData);
+		clone.setId(newId);
+		return clone;
+	}
+
+}

src/main/java/org/qortal/network/message/AccountMessage.java

@@ -0,0 +1,93 @@
+package org.qortal.network.message;
+
+import com.google.common.primitives.Ints;
+import org.qortal.data.account.AccountData;
+import org.qortal.transform.Transformer;
+import org.qortal.utils.Base58;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+public class AccountMessage extends Message {
+
+	private static final int ADDRESS_LENGTH = Transformer.ADDRESS_LENGTH;
+	private static final int REFERENCE_LENGTH = Transformer.SIGNATURE_LENGTH;
+	private static final int PUBLIC_KEY_LENGTH = Transformer.PUBLIC_KEY_LENGTH;
+
+	private AccountData accountData;
+
+	public AccountMessage(AccountData accountData) {
+		super(MessageType.ACCOUNT);
+
+		ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+		try {
+			// Send raw address instead of base58 encoded
+			byte[] address = Base58.decode(accountData.getAddress());
+			bytes.write(address);
+
+			bytes.write(accountData.getReference());
+
+			bytes.write(accountData.getPublicKey());
+
+			bytes.write(Ints.toByteArray(accountData.getDefaultGroupId()));
+
+			bytes.write(Ints.toByteArray(accountData.getFlags()));
+
+			bytes.write(Ints.toByteArray(accountData.getLevel()));
+
+			bytes.write(Ints.toByteArray(accountData.getBlocksMinted()));
+
+			bytes.write(Ints.toByteArray(accountData.getBlocksMintedAdjustment()));
+
+		} catch (IOException e) {
+			throw new AssertionError("IOException shouldn't occur with ByteArrayOutputStream");
+		}
+
+		this.dataBytes = bytes.toByteArray();
+		this.checksumBytes = Message.generateChecksum(this.dataBytes);
+	}
+
+	public AccountMessage(int id, AccountData accountData) {
+		super(id, MessageType.ACCOUNT);
+
+		this.accountData = accountData;
+	}
+
+	public AccountData getAccountData() {
+		return this.accountData;
+	}
+
+	public static Message fromByteBuffer(int id, ByteBuffer byteBuffer) {
+		byte[] addressBytes = new byte[ADDRESS_LENGTH];
+		byteBuffer.get(addressBytes);
+		String address = Base58.encode(addressBytes);
+
+		byte[] reference = new byte[REFERENCE_LENGTH];
+		byteBuffer.get(reference);
+
+		byte[] publicKey = new byte[PUBLIC_KEY_LENGTH];
+		byteBuffer.get(publicKey);
+
+		int defaultGroupId = byteBuffer.getInt();
+
+		int flags = byteBuffer.getInt();
+
+		int level = byteBuffer.getInt();
+
+		int blocksMinted = byteBuffer.getInt();
+
+		int blocksMintedAdjustment = byteBuffer.getInt();
+
+		AccountData accountData = new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment);
+		return new AccountMessage(id, accountData);
+	}
+
+	public AccountMessage cloneWithNewId(int newId) {
+		AccountMessage clone = new AccountMessage(this.accountData);
+		clone.setId(newId);
+		return clone;
+	}
+
+}