Speed up status rebuilding by excluding transactions that aren't hosted locally by the node.

This is a short term limit, is well above current usage levels, and can be increased substantially in future once the block minter code has been improved.

.github/workflows/pr-testing.yml

@@ -8,16 +8,16 @@ jobs:
   mavenTesting:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: Cache local Maven repository
-      uses: actions/cache@v2
+      uses: actions/cache@v3
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
         restore-keys: |
           ${{ runner.os }}-maven-
     - name: Set up the Java JDK
-      uses: actions/setup-java@v2
+      uses: actions/setup-java@v3
       with:
         java-version: '11'
         distribution: 'adopt'

.gitignore

@@ -14,7 +14,6 @@
 /.mvn.classpath
 /notes*
 /settings.json
-/testnet*
 /settings*.json
 /testchain*.json
 /run-testnet*.sh

Q-Apps.md

@@ -0,0 +1,919 @@
+# Qortal Project - Q-Apps Documentation
+
+## Introduction
+
+Q-Apps are static web apps written in javascript, HTML, CSS, and other static assets. The key difference between a Q-App and a fully static site is its ability to interact with both the logged-in user and on-chain data. This is achieved using the API described in this document.
+
+
+# Section 0: Basic QDN concepts
+
+## Introduction to QDN resources
+Each published item on QDN (Qortal Data Network) is referred to as a "resource". A resource could contain anything from a few characters of text, to a multi-layered directory structure containing thousands of files.
+
+Resources are stored on-chain, however the data payload is generally stored off-chain, and verified using an on-chain SHA-256 hash.
+
+To publish a resource, a user must first register a name, and then include that name when publishing the data. Accounts without a registered name are unable to publish to QDN from a Q-App at this time.
+
+Owning the name grants update privileges to the data. If that name is later sold or transferred, the permission to update that resource is moved to the new owner.
+
+
+## Name, service & identifier
+
+Each QDN resource has 3 important fields:
+- `name` - the registered name of the account that is publishing the data (which will hold update/edit privileges going forwards).<br /><br />
+- `service` - the type of content (e.g. IMAGE or JSON). Different services have different validation rules. See [list of available services](#services).<br /><br />
+- `identifier` - an optional string to allow more than one resource to exist for a given name/service combination. For example, the name `QortalDemo` may wish to publish multiple images. This can be achieved by using a different identifier string for each. The identifier is only unique to the name in question, and so it doesn't matter if another name is using the same service and identifier string.
+
+
+## Shared identifiers
+
+Since an identifier can be used by multiple names, this can be used to the advantage of Q-App developers as it allows for data to be stored in a deterministic location.
+
+An example of this is the user's avatar. This will always be published with service `THUMBNAIL` and identifier `qortal_avatar`, along with the user's name. So, an app can display the avatar of a user just by specifying their name when requesting the data. The same applies when publishing data.
+
+
+## "Default" resources
+
+A "default" resource refers to one without an identifier. For example, when a website is published via the UI, it will use the user's name and the service `WEBSITE`. These do not have an identifier, and are therefore the "default" website for this name. When requesting or publishing data without an identifier, apps can either omit the `identifier` key entirely, or include `"identifier": "default"` to indicate that the resource(s) being queried or published do not have an identifier.
+
+
+<a name="services"></a>
+## Available service types
+
+Here is a list of currently available services that can be used in Q-Apps:
+
+### Public services ###
+The services below are intended to be used for publicly accessible data.
+
+IMAGE,
+THUMBNAIL,
+VIDEO,
+AUDIO,
+PODCAST,
+VOICE,
+ARBITRARY_DATA,
+JSON,
+DOCUMENT,
+LIST,
+PLAYLIST,
+METADATA,
+BLOG,
+BLOG_POST,
+BLOG_COMMENT,
+GIF_REPOSITORY,
+ATTACHMENT,
+FILE,
+FILES,
+CHAIN_DATA,
+STORE,
+PRODUCT,
+OFFER,
+COUPON,
+CODE,
+PLUGIN,
+EXTENSION,
+GAME,
+ITEM,
+NFT,
+DATABASE,
+SNAPSHOT,
+COMMENT,
+CHAIN_COMMENT,
+WEBSITE,
+APP,
+QCHAT_ATTACHMENT,
+QCHAT_IMAGE,
+QCHAT_AUDIO,
+QCHAT_VOICE
+
+### Private services ###
+For the services below, data is encrypted for a single recipient, and can only be decrypted using the private key of the recipient's wallet.
+
+QCHAT_ATTACHMENT_PRIVATE,
+ATTACHMENT_PRIVATE,
+FILE_PRIVATE,
+IMAGE_PRIVATE,
+VIDEO_PRIVATE,
+AUDIO_PRIVATE,
+VOICE_PRIVATE,
+DOCUMENT_PRIVATE,
+MAIL_PRIVATE,
+MESSAGE_PRIVATE
+
+
+## Single vs multi-file resources
+
+Some resources, such as those published with the `IMAGE` or `JSON` service, consist of a single file or piece of data (the image or the JSON string). This is the most common type of QDN resource, especially in the context of Q-Apps. These can be published by supplying a base64-encoded string containing the data.
+
+Other resources, such as those published with the `WEBSITE`, `APP`, or `GIF_REPOSITORY` service, can contain multiple files and directories. Publishing these kinds of files is not yet available for Q-Apps, however it is possible to retrieve multi-file resources that are already published. When retrieving this data (via FETCH_QDN_RESOURCE), a `filepath` must be included to indicate the file that you would like to retrieve. There is no need to specify a filepath for single file resources, as these will automatically return the contents of the single file.
+
+
+## App-specific data
+
+Some apps may want to make all QDN data for a particular service available. However, others may prefer to only deal with data that has been published by their app (if a specific format/schema is being used for instance).
+
+Identifiers can be used to allow app developers to locate data that has been published by their app. The recommended approach for this is to use the app name as a prefix on all identifiers when publishing data.
+
+For instance, an app called `MyApp` could allow users to publish JSON data. The app could choose to prefix all identifiers with the string `myapp_`, and then use a random string for each published resource (resulting in identifiers such as `myapp_qR5ndZ8v`). Then, to locate data that has potentially been published by users of MyApp, it can later search the QDN database for items with `"service": "JSON"` and `"identifier": "myapp_"`. The SEARCH_QDN_RESOURCES action has a `prefix` option in order to match identifiers beginning with the supplied string.
+
+Note that QDN is a permissionless system, and therefore it's not possible to verify that a resource was actually published by the app. It is recommended that apps validate the contents of the resource to ensure it is formatted correctly, instead of making assumptions.
+
+
+## Updating a resource
+
+To update a resource, it can be overwritten by publishing with the same `name`, `service`, and `identifier` combination. Note that the authenticated account must currently own the name in order to publish an update.
+
+
+## Routing
+
+If a non-existent `filepath` is accessed, the default behaviour of QDN is to return a `404: File not found` error. This includes anything published using the `WEBSITE` service.
+
+However, routing is handled differently for anything published using the `APP` service. 
+
+For apps, QDN automatically sends all unhandled requests to the index file (generally index.html). This allows the app to use custom routing, as it is able to listen on any path. If a file exists at a path, the file itself will be served, and so the request won't be sent to the index file.
+
+It's recommended that all apps return a 404 page if a request isn't able to be routed.
+
+
+# Section 1: Simple links and image loading via HTML
+
+## Section 1a: Linking to other QDN websites / resources
+
+The `qortal://` protocol can be used to access QDN data from within Qortal websites and apps. The basic format is as follows:
+```
+<a href="qortal://{service}/{name}/{identifier}/{path}">link text</a>
+```
+
+However, the system will support the omission of the `identifier` and/or `path` components to allow for simpler URL formats.
+
+A simple link to another website can be achieved with this HTML code:
+```
+<a href="qortal://WEBSITE/QortalDemo">link text</a>
+```
+
+To link to a specific page of another website:
+```
+<a href="qortal://WEBSITE/QortalDemo/minting-leveling/index.html">link text</a>
+```
+
+To link to a standalone resource, such as an avatar
+```
+<a href="qortal://THUMBNAIL/QortalDemo/qortal_avatar">avatar</a>
+```
+
+For cases where you would prefer to explicitly include an identifier (to remove ambiguity) you can use the keyword `default` to access a resource that doesn't have an identifier. For instance:
+```
+<a href="qortal://WEBSITE/QortalDemo/default">link to root of website</a>
+<a href="qortal://WEBSITE/QortalDemo/default/minting-leveling/index.html">link to subpage of website</a>
+```
+
+
+## Section 1b: Linking to other QDN images
+
+The same applies for images, such as displaying an avatar:
+```
+<img src="qortal://THUMBNAIL/QortalDemo/qortal_avatar" />
+```
+
+...or even an image from an entirely different website:
+```
+<img src="qortal://WEBSITE/AlphaX/assets/img/logo.png" />
+```
+
+
+# Section 2: Integrating a Javascript app
+
+Javascript apps allow for much more complex integrations with Qortal's blockchain data.
+
+## Section 2a: Direct API calls
+
+The standard [Qortal Core API](http://localhost:12391/api-documentation) is available to websites and apps, and can be called directly using a standard AJAX request, such as:
+```
+async function getNameInfo(name) {
+    const response = await fetch("/names/" + name);
+    const nameData = await response.json();
+    console.log("nameData: " + JSON.stringify(nameData));
+}
+getNameInfo("QortalDemo");
+```
+
+However, this only works for read-only data, such as looking up transactions, names, balances, etc. Also, since the address of the logged in account can't be retrieved from the core, apps can't show personalized data with this approach.
+
+
+## Section 2b: User interaction via qortalRequest()
+
+To take things a step further, the qortalRequest() function can be used to interact with the user, in order to:
+
+- Request address and public key of the logged in account
+- Publish data to QDN
+- Send chat messages
+- Join groups
+- Deploy ATs (smart contracts)
+- Send QORT or any supported foreign coin
+- Add/remove items from lists
+
+In addition to the above, qortalRequest() also supports many read-only functions that are also available via direct core API calls. Using qortalRequest() helps with futureproofing, as the core APIs can be modified without breaking functionality of existing Q-Apps.
+
+
+### Making a request
+
+Qortal core will automatically inject the `qortalRequest()` javascript function to all websites/apps, which returns a Promise. This can be used to fetch data or publish data to the Qortal blockchain. This functionality supports async/await, as well as try/catch error handling.
+
+```
+async function myfunction() {
+    try {
+        let res = await qortalRequest({
+            action: "GET_ACCOUNT_DATA",
+            address: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2"
+        });
+        console.log(JSON.stringify(res)); // Log the response to the console
+    
+    } catch(e) {
+        console.log("Error: " + JSON.stringify(e));
+    }
+}
+myfunction();
+```
+
+### Timeouts
+
+Request timeouts are handled automatically when using qortalRequest(). The timeout value will differ based on the action being used - see `getDefaultTimeout()` in [q-apps.js](src/main/resources/q-apps/q-apps.js) for the current values.
+
+If a request times out it will throw an error - `The request timed out` - which can be handled by the Q-App.
+
+It is also possible to specify a custom timeout using `qortalRequestWithTimeout(request, timeout)`, however this is discouraged. It's more reliable and futureproof to let the core handle the timeout values.
+
+
+# Section 3: qortalRequest Documentation
+
+## Supported actions
+
+Here is a list of currently supported actions:
+- GET_USER_ACCOUNT
+- GET_ACCOUNT_DATA
+- GET_ACCOUNT_NAMES
+- SEARCH_NAMES
+- GET_NAME_DATA
+- LIST_QDN_RESOURCES
+- SEARCH_QDN_RESOURCES
+- GET_QDN_RESOURCE_STATUS
+- GET_QDN_RESOURCE_PROPERTIES
+- GET_QDN_RESOURCE_METADATA
+- GET_QDN_RESOURCE_URL
+- LINK_TO_QDN_RESOURCE
+- FETCH_QDN_RESOURCE
+- PUBLISH_QDN_RESOURCE
+- PUBLISH_MULTIPLE_QDN_RESOURCES
+- DECRYPT_DATA
+- SAVE_FILE
+- GET_WALLET_BALANCE
+- GET_BALANCE
+- SEND_COIN
+- SEARCH_CHAT_MESSAGES
+- SEND_CHAT_MESSAGE
+- LIST_GROUPS
+- JOIN_GROUP
+- DEPLOY_AT
+- GET_AT
+- GET_AT_DATA
+- LIST_ATS
+- FETCH_BLOCK
+- FETCH_BLOCK_RANGE
+- SEARCH_TRANSACTIONS
+- GET_PRICE
+- GET_LIST_ITEMS
+- ADD_LIST_ITEMS
+- DELETE_LIST_ITEM
+
+More functionality will be added in the future.
+
+## Example Requests
+
+Here are some example requests for each of the above:
+
+### Get address of logged in account
+_Will likely require user approval_
+```
+let account = await qortalRequest({
+     action: "GET_USER_ACCOUNT"
+});
+let address = account.address;
+```
+
+### Get public key of logged in account
+_Will likely require user approval_
+```
+let pubkey = await qortalRequest({
+     action: "GET_USER_ACCOUNT"
+});
+let publicKey = account.publicKey;
+```
+
+### Get account data
+```
+let res = await qortalRequest({
+    action: "GET_ACCOUNT_DATA",
+    address: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2"
+});
+```
+
+### Get names owned by account
+```
+let res = await qortalRequest({
+    action: "GET_ACCOUNT_NAMES",
+    address: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2"
+});
+```
+
+### Search names
+```
+let res = await qortalRequest({
+    action: "SEARCH_NAMES",
+    query: "search query goes here",
+    prefix: false, // Optional - if true, only the beginning of the name is matched
+    limit: 100,
+    offset: 0,
+    reverse: false
+});
+```
+
+### Get name data
+```
+let res = await qortalRequest({
+    action: "GET_NAME_DATA",
+    name: "QortalDemo"
+});
+```
+
+
+### List QDN resources
+```
+let res = await qortalRequest({
+    action: "LIST_QDN_RESOURCES",
+    service: "THUMBNAIL",
+    name: "QortalDemo", // Optional (exact match)
+    identifier: "qortal_avatar", // Optional (exact match)
+    default: true, // Optional
+    includeStatus: false, // Optional - will take time to respond, so only request if necessary
+    includeMetadata: false, // Optional - will take time to respond, so only request if necessary
+    followedOnly: false, // Optional - include followed names only
+    excludeBlocked: false, // Optional - exclude blocked content
+    limit: 100,
+    offset: 0,
+    reverse: true
+});
+```
+
+### Search QDN resources
+```
+let res = await qortalRequest({
+    action: "SEARCH_QDN_RESOURCES",
+    service: "THUMBNAIL",
+    query: "search query goes here", // Optional - searches both "identifier" and "name" fields
+    identifier: "search query goes here", // Optional - searches only the "identifier" field
+    name: "search query goes here", // Optional - searches only the "name" field
+    prefix: false, // Optional - if true, only the beginning of fields are matched in all of the above filters
+    exactMatchNames: true, // Optional - if true, partial name matches are excluded
+    default: false, // Optional - if true, only resources without identifiers are returned
+    mode: "LATEST", // Optional - whether to return all resources or just the latest for a name/service combination. Possible values: ALL,LATEST. Default: LATEST
+    minLevel: 1, // Optional - whether to filter results by minimum account level
+    includeStatus: false, // Optional - will take time to respond, so only request if necessary
+    includeMetadata: false, // Optional - will take time to respond, so only request if necessary
+    nameListFilter: "QApp1234Subscriptions", // Optional - will only return results if they are from a name included in supplied list
+    followedOnly: false, // Optional - include followed names only
+    excludeBlocked: false, // Optional - exclude blocked content
+    // before: 1683546000000, // Optional - limit to resources created before timestamp
+    // after: 1683546000000, // Optional - limit to resources created after timestamp
+    limit: 100,
+    offset: 0,
+    reverse: true
+});
+```
+
+### Search QDN resources (multiple names)
+```
+let res = await qortalRequest({
+    action: "SEARCH_QDN_RESOURCES",
+    service: "THUMBNAIL",
+    query: "search query goes here", // Optional - searches both "identifier" and "name" fields
+    identifier: "search query goes here", // Optional - searches only the "identifier" field
+    names: ["QortalDemo", "crowetic", "AlphaX"], // Optional - searches only the "name" field for any of the supplied names
+    prefix: false, // Optional - if true, only the beginning of fields are matched in all of the above filters
+    exactMatchNames: true, // Optional - if true, partial name matches are excluded
+    default: false, // Optional - if true, only resources without identifiers are returned
+    mode: "LATEST", // Optional - whether to return all resources or just the latest for a name/service combination. Possible values: ALL,LATEST. Default: LATEST
+    includeStatus: false, // Optional - will take time to respond, so only request if necessary
+    includeMetadata: false, // Optional - will take time to respond, so only request if necessary
+    nameListFilter: "QApp1234Subscriptions", // Optional - will only return results if they are from a name included in supplied list
+    followedOnly: false, // Optional - include followed names only
+    excludeBlocked: false, // Optional - exclude blocked content
+    // before: 1683546000000, // Optional - limit to resources created before timestamp
+    // after: 1683546000000, // Optional - limit to resources created after timestamp
+    limit: 100,
+    offset: 0,
+    reverse: true
+});
+```
+
+### Fetch QDN single file resource
+```
+let res = await qortalRequest({
+    action: "FETCH_QDN_RESOURCE",
+    name: "QortalDemo",
+    service: "THUMBNAIL",
+    identifier: "qortal_avatar", // Optional. If omitted, the default resource is returned, or you can alternatively use the keyword "default"
+    encoding: "base64", // Optional. If omitted, data is returned in raw form
+    rebuild: false
+});
+```
+
+### Fetch file from multi file QDN resource
+Data is returned in the base64 format
+```
+let res = await qortalRequest({
+    action: "FETCH_QDN_RESOURCE",
+    name: "QortalDemo",
+    service: "WEBSITE",
+    identifier: "default", // Optional. If omitted, the default resource is returned, or you can alternatively request that using the keyword "default", as shown here
+    filepath: "index.html", // Required only for resources containing more than one file
+    rebuild: false
+});
+```
+
+### Get QDN resource status
+```
+let res = await qortalRequest({
+    action: "GET_QDN_RESOURCE_STATUS",
+    name: "QortalDemo",
+    service: "THUMBNAIL",
+    identifier: "qortal_avatar", // Optional
+    build: true // Optional - request that the resource is fetched & built in the background
+});
+```
+
+### Get QDN resource properties
+```
+let res = await qortalRequest({
+    action: "GET_QDN_RESOURCE_PROPERTIES",
+    name: "QortalDemo",
+    service: "THUMBNAIL",
+    identifier: "qortal_avatar" // Optional
+});
+// Returns: filename, size, mimeType (where available)
+```
+
+### Get QDN resource metadata
+```
+let res = await qortalRequest({
+    action: "GET_QDN_RESOURCE_METADATA",
+    name: "QortalDemo",
+    service: "THUMBNAIL",
+    identifier: "qortal_avatar" // Optional
+});
+```
+
+### Publish a single file to QDN
+_Requires user approval_.<br />
+Note: this publishes a single, base64-encoded file. Multi-file resource publishing (such as a WEBSITE or GIF_REPOSITORY) is not yet supported via a Q-App. It will be added in a future update.
+```
+let res = await qortalRequest({
+    action: "PUBLISH_QDN_RESOURCE",
+    name: "Demo", // Publisher must own the registered name - use GET_ACCOUNT_NAMES for a list
+    service: "IMAGE",
+    identifier: "myapp-image1234" // Optional
+    data64: "base64_encoded_data",
+    // filename: "image.jpg", // Optional - to help apps determine the file's type
+    // title: "Title", // Optional
+    // description: "Description", // Optional
+    // category: "TECHNOLOGY", // Optional
+    // tag1: "any", // Optional
+    // tag2: "strings", // Optional
+    // tag3: "can", // Optional
+    // tag4: "go", // Optional
+    // tag5: "here", // Optional
+    // encrypt: true, // Optional - to be used with a private service
+    // recipientPublicKey: "publickeygoeshere" // Only required if `encrypt` is set to true
+});
+```
+
+### Publish multiple resources at once to QDN
+_Requires user approval_.<br />
+Note: each resource being published consists of a single, base64-encoded file, each in its own transaction. Useful for publishing two or more related things, such as a video and a video thumbnail.
+```
+let res = await qortalRequest({
+    action: "PUBLISH_MULTIPLE_QDN_RESOURCES",
+    resources: [
+        name: "Demo", // Publisher must own the registered name - use GET_ACCOUNT_NAMES for a list
+        service: "IMAGE",
+        identifier: "myapp-image1234" // Optional
+        data64: "base64_encoded_data",
+        // filename: "image.jpg", // Optional - to help apps determine the file's type
+        // title: "Title", // Optional
+        // description: "Description", // Optional
+        // category: "TECHNOLOGY", // Optional
+        // tag1: "any", // Optional
+        // tag2: "strings", // Optional
+        // tag3: "can", // Optional
+        // tag4: "go", // Optional
+        // tag5: "here", // Optional
+        // encrypt: true, // Optional - to be used with a private service
+        // recipientPublicKey: "publickeygoeshere" // Only required if `encrypt` is set to true
+    ],
+    [
+        ... more resources here if needed ...
+    ]
+});
+```
+
+### Decrypt encrypted/private data
+```
+let res = await qortalRequest({
+    action: "DECRYPT_DATA",
+    encryptedData: 'qortalEncryptedDatabMx4fELNTV+ifJxmv4+GcuOIJOTo+3qAvbWKNY2L1r',
+    publicKey: 'publickeygoeshere'
+});
+// Returns base64 encoded string of plaintext data
+```
+
+### Prompt user to save a file to disk
+Note: mimeType not required but recommended. If not specified, saving will fail if the mimeType is unable to be derived from the Blob.
+```
+let res = await qortalRequest({
+    action: "SAVE_FILE",
+    blob: dataBlob,
+    filename: "myfile.pdf",
+    mimeType: "application/pdf" // Optional but recommended
+});
+```
+
+
+### Get wallet balance (QORT)
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "GET_WALLET_BALANCE",
+    coin: "QORT"
+});
+```
+
+
+### Get address or asset balance
+```
+let res = await qortalRequest({
+    action: "GET_BALANCE",
+    address: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2"
+});
+```
+```
+let res = await qortalRequest({
+    action: "GET_BALANCE",
+    assetId: 1,
+    address: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2"
+});
+```
+
+### Send QORT to address
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "SEND_COIN",
+    coin: "QORT",
+    destinationAddress: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2",
+    amount: 1.00000000 // 1 QORT
+});
+```
+
+### Send foreign coin to address
+_Requires user approval_<br />
+Note: default fees can be found [here](https://github.com/Qortal/qortal-ui/blob/master/plugins/plugins/core/qdn/browser/browser.src.js#L205-L209).
+```
+let res = await qortalRequest({
+    action: "SEND_COIN",
+    coin: "LTC",
+    destinationAddress: "LSdTvMHRm8sScqwCi6x9wzYQae8JeZhx6y",
+    amount: 1.00000000, // 1 LTC
+    fee: 0.00000020 // Optional fee per byte (default fee used if omitted, recommended) - not used for QORT or ARRR
+});
+```
+
+### Search or list chat messages
+```
+let res = await qortalRequest({
+    action: "SEARCH_CHAT_MESSAGES",
+    before: 999999999999999,
+    after: 0,
+    txGroupId: 0, // Optional (must specify either txGroupId or two involving addresses)
+    // involving: ["QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2", "QSefrppsDCsZebcwrqiM1gNbWq7YMDXtG2"], // Optional (must specify either txGroupId or two involving addresses)
+    // reference: "reference", // Optional
+    // chatReference: "chatreference", // Optional
+    // hasChatReference: true, // Optional
+    encoding: "BASE64", // Optional (defaults to BASE58 if omitted)
+    limit: 100,
+    offset: 0,
+    reverse: true
+});
+```
+
+### Send a group chat message
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "SEND_CHAT_MESSAGE",
+    groupId: 0,
+    message: "Test"
+});
+```
+
+### Send a private chat message
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "SEND_CHAT_MESSAGE",
+    destinationAddress: "QZLJV7wbaFyxaoZQsjm6rb9MWMiDzWsqM2",
+    message: "Test"
+});
+```
+
+### List groups
+```
+let res = await qortalRequest({
+    action: "LIST_GROUPS",
+    limit: 100,
+    offset: 0,
+    reverse: true
+});
+```
+
+### Join a group
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "JOIN_GROUP",
+    groupId: 100
+});
+```
+
+
+### Deploy an AT
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "DEPLOY_AT",
+    creationBytes: "12345", // Must be Base58 encoded
+    name: "test name",
+    description: "test description",
+    type: "test type",
+    tags: "test tags",
+    amount: 1.00000000, // 1 QORT
+    assetId: 0,
+    // fee: 0.002 // optional - will use default fee if excluded
+});
+```
+
+### Get AT info
+```
+let res = await qortalRequest({
+    action: "GET_AT",
+    atAddress: "ASRUsCjk6fa5bujv3oWYmWaVqNtvxydpPH"
+});
+```
+
+### Get AT data bytes (base58 encoded)
+```
+let res = await qortalRequest({
+    action: "GET_AT_DATA",
+    atAddress: "ASRUsCjk6fa5bujv3oWYmWaVqNtvxydpPH"
+});
+```
+
+### List ATs by functionality
+```
+let res = await qortalRequest({
+    action: "LIST_ATS",
+    codeHash58: "4KdJETRAdymE7dodDmJbf5d9L1bp4g5Nxky8m47TBkvA",
+    isExecutable: true,
+    limit: 100,
+    offset: 0,
+    reverse: true
+});
+```
+
+### Fetch block by signature
+```
+let res = await qortalRequest({
+    action: "FETCH_BLOCK",
+    signature: "875yGFUy1zHV2hmxNWzrhtn9S1zkeD7SQppwdXFysvTXrankCHCz4iyAUgCBM3GjvibbnyRQpriuy1cyu953U1u5uQdzuH3QjQivi9UVwz86z1Akn17MGd5Z5STjpDT7248K6vzMamuqDei57Znonr8GGgn8yyyABn35CbZUCeAuXju"
+});
+```
+
+### Fetch block by height
+```
+let res = await qortalRequest({
+    action: "FETCH_BLOCK",
+    height: "1139850"
+});
+```
+
+### Fetch a range of blocks
+```
+let res = await qortalRequest({
+    action: "FETCH_BLOCK_RANGE",
+    height: "1139800",
+    count: 20,
+    reverse: false
+});
+```
+
+### Search transactions
+```
+let res = await qortalRequest({
+    action: "SEARCH_TRANSACTIONS",
+    // startBlock: 1139000,
+    // blockLimit: 1000,
+    txGroupId: 0,
+    txType: [
+        "PAYMENT",
+        "REWARD_SHARE"
+    ],
+    confirmationStatus: "CONFIRMED",
+    limit: 10,
+    offset: 0,
+    reverse: false
+});
+```
+
+### Get an estimate of the QORT price
+```
+let res = await qortalRequest({
+    action: "GET_PRICE",
+    blockchain: "LITECOIN",
+    // maxtrades: 10,
+    inverse: true
+});
+```
+
+### Get URL to load a QDN resource
+Note: this returns a "Resource does not exist" error if a non-existent resource is requested.
+```
+let url = await qortalRequest({
+    action: "GET_QDN_RESOURCE_URL",
+    service: "THUMBNAIL",
+    name: "QortalDemo",
+    identifier: "qortal_avatar"
+    // path: "filename.jpg" // optional - not needed if resource contains only one file
+});
+```
+
+### Get URL to load a QDN website
+Note: this returns a "Resource does not exist" error if a non-existent resource is requested.
+```
+let url = await qortalRequest({
+    action: "GET_QDN_RESOURCE_URL",
+    service: "WEBSITE",
+    name: "QortalDemo",
+});
+```
+
+### Get URL to load a specific file from a QDN website
+Note: this returns a "Resource does not exist" error if a non-existent resource is requested.
+```
+let url = await qortalRequest({
+    action: "GET_QDN_RESOURCE_URL",
+    service: "WEBSITE",
+    name: "AlphaX",
+    path: "/assets/img/logo.png"
+});
+```
+
+### Link/redirect to another QDN website
+Note: an alternate method is to include `<a href="qortal://WEBSITE/QortalDemo">link text</a>` within your HTML code.
+```
+let res = await qortalRequest({
+    action: "LINK_TO_QDN_RESOURCE",
+    service: "WEBSITE",
+    name: "QortalDemo",
+});
+```
+
+### Link/redirect to a specific path of another QDN website
+Note: an alternate method is to include `<a href="qortal://WEBSITE/QortalDemo/minting-leveling/index.html">link text</a>` within your HTML code.
+```
+let res = await qortalRequest({
+    action: "LINK_TO_QDN_RESOURCE",
+    service: "WEBSITE",
+    name: "QortalDemo",
+    path: "/minting-leveling/index.html"
+});
+```
+
+### Get the contents of a list
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "GET_LIST_ITEMS",
+    list_name: "followedNames"
+});
+```
+
+### Add one or more items to a list
+_Requires user approval_
+```
+let res = await qortalRequest({
+    action: "ADD_LIST_ITEMS",
+    list_name: "blockedNames",
+    items: ["QortalDemo"]
+});
+```
+
+### Delete a single item from a list
+_Requires user approval_.
+Items must be deleted one at a time.
+```
+let res = await qortalRequest({
+    action: "DELETE_LIST_ITEM",
+    list_name: "blockedNames",
+    item: "QortalDemo"
+});
+```
+
+
+# Section 4: Examples
+
+Some example projects can be found [here](https://github.com/Qortal/Q-Apps). These can be cloned and modified, or used as a reference when creating a new app.
+
+
+## Sample App
+
+Here is a sample application to display the logged-in user's avatar:
+```
+<html>
+<head>
+    <script>
+        async function showAvatar() {
+            try {
+                // Get QORT address of logged in account
+                let account = await qortalRequest({
+                    action: "GET_USER_ACCOUNT"
+                });
+                let address = account.address;
+                console.log("address: " + address);
+            
+                // Get names owned by this account
+                let names = await qortalRequest({
+                    action: "GET_ACCOUNT_NAMES",
+                    address: address
+                });
+                console.log("names: " + JSON.stringify(names));
+            
+                if (names.length == 0) {
+                    console.log("User has no registered names");
+                    return;
+                }
+            
+                // Download base64-encoded avatar of the first registered name
+                let avatar = await qortalRequest({
+                    action: "FETCH_QDN_RESOURCE",
+                    name: names[0].name,
+                    service: "THUMBNAIL",
+                    identifier: "qortal_avatar",
+                    encoding: "base64"
+                });
+                console.log("Avatar size: " + avatar.length + " bytes");
+            
+                // Display the avatar image on the screen
+                document.getElementById("avatar").src = "data:image/png;base64," + avatar;
+                
+            } catch(e) {
+                console.log("Error: " + JSON.stringify(e));
+            }
+        }
+    </script>
+</head>
+<body onload="showAvatar()">
+    <img width="500" id="avatar" />
+</body>
+</html>
+```
+
+
+# Section 5: Testing and Development
+
+Publishing an in-development app to mainnet isn't recommended. There are several options for developing and testing a Q-app before publishing to mainnet:
+
+### Preview mode
+
+Select "Preview" in the UI after choosing the zip. This allows for full Q-App testing without the need to publish any data.
+
+
+### Testnets
+
+For an end-to-end test of Q-App publishing, you can use the official testnet, or set up a single node testnet of your own (often referred to as devnet) on your local machine. See [Single Node Testnet Quick Start Guide](testnet/README.md#quick-start).
+
+
+### Debugging
+
+It is recommended that you develop and test in a web browser, to allow access to the javascript console. To do this:
+1. Open the UI app, then minimise it.
+2. In a Chromium-based web browser, visit: http://localhost:12388/
+3. Log in to your account and then preview your app/website.
+4. Go to `View > Developer > JavaScript Console`. Here you can monitor console logs, errors, and network requests from your app, in the same way as any other web-app.

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:{7DED0630-60A3-438A-B857-D95BD16213F1} 1049:{4A7BAAA1-E9EC-4E92-8963-34420EC1E3F4} 2052:{F3448469-4E4F-4600-AE05-DF7669B267E3} 2057:{0B980BC5-4C80-4A98-A4D2-B32D134AA276} " Type="16"/>
+    <ROW Property="ProductCode" Value="1033:{CB85115E-ECCE-4B3D-BB7F-6251A2764922} 1049:{09AC1C62-4E33-4312-826A-38F597ED1B17} 2052:{3CF701B3-E118-4A31-A4B7-156CEA19FBCC} 2057:{468F337D-0EF8-41D1-B5DE-4EEE66BA2AF6} " Type="16"/>
     <ROW Property="ProductLanguage" Value="2057"/>
     <ROW Property="ProductName" Value="Qortal"/>
-    <ROW Property="ProductVersion" Value="3.3.5" Type="32"/>
+    <ROW Property="ProductVersion" Value="3.8.5" 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="{191AD445-72DF-4850-BB4A-FE92D4B62BCF}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
+    <ROW Component="AI_CustomARPName" ComponentId="{094B5D07-2258-4A39-9917-2E2F7F6E210B}" 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"/>
@@ -1173,7 +1173,7 @@
     <ROW Action="AI_STORE_LOCATION" Type="51" Source="ARPINSTALLLOCATION" Target="[APPDIR]"/>
     <ROW Action="AI_SetPermissions" Type="11265" Source="userAccounts.dll" Target="OnSetPermissions" WithoutSeq="true"/>
     <ROW Action="CustomizeLog4j2PropertiesScript" Type="3109" Target="Script Text" TargetUnformatted="var actionData = Session.Property(&quot;CustomActionData&quot;);&#13;&#10;var actionDataArray = actionData.split(&quot;|&quot;);&#13;&#10;var appDir = actionDataArray[0];&#13;&#10;var dataFolder = actionDataArray[1] + actionDataArray[2] + &quot;\\&quot;;&#13;&#10;&#13;&#10;var ForReading = 1, ForWriting = 2, ForAppending = 8;&#13;&#10;var fso = new ActiveXObject(&quot;Scripting.FileSystemObject&quot;);&#13;&#10;&#13;&#10;// Make copy&#13;&#10;fso.CopyFile(appDir + &quot;log4j2.properties&quot;, appDir + &quot;log4j2-orig.properties&quot;, true); // overwrite&#13;&#10;&#13;&#10;// Rewrite %AppDir%\log4j2.properties to update logfile storage path&#13;&#10;var fin = fso.OpenTextFile(appDir + &quot;log4j2-orig.properties&quot;, ForReading, false); // no create&#13;&#10;var fout = fso.OpenTextFile(appDir + &quot;log4j2.properties&quot;, ForWriting, true); // can create&#13;&#10;&#13;&#10;// Copy lines with rewriting where necessary&#13;&#10;while( !fin.AtEndOfStream ) {&#13;&#10;&#9;var line = fin.ReadLine();&#13;&#10;&#13;&#10;&#9;var start = line.indexOf(&quot;property.dirname&quot;);&#13;&#10;&#9;if (start &gt; 0) {&#13;&#10;&#9;&#9;// line: # property.dirname = ...appdata...&#13;&#10;&#9;&#9;// uncomment/replace this line for Windows&#13;&#10;&#9;&#9;fout.WriteLine( &quot;property.dirname = &quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) );&#13;&#10;&#9;} else {&#13;&#10;&#9;&#9;// not found - output verbatim&#13;&#10;&#9;&#9;fout.WriteLine( line );&#13;&#10;&#9;}&#13;&#10;}&#13;&#10;&#13;&#10;fin.Close();&#13;&#10;fout.Close();&#13;&#10;" AdditionalSeq="AI_DATA_SETTER_4"/>
-    <ROW Action="CustomizeSettingsJsonScript" Type="3109" Target="Script Text" TargetUnformatted="var actionData = Session.Property(&quot;CustomActionData&quot;);&#13;&#10;var actionDataArray = actionData.split(&quot;|&quot;);&#13;&#10;var appDir = actionDataArray[0];&#13;&#10;var dataFolder = actionDataArray[1] + actionDataArray[2] + &quot;\\&quot;;&#13;&#10;&#13;&#10;var ForReading = 1, ForWriting = 2, ForAppending = 8;&#13;&#10;var fso = new ActiveXObject(&quot;Scripting.FileSystemObject&quot;);&#13;&#10;&#13;&#10;// Create basic %APPDIR%\settings.json with path to real settings.json in dataFolder&#13;&#10;var fts = fso.OpenTextFile(appDir + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;fts.WriteLine( &quot;{&quot; );&#13;&#10;// We need to escape Windows path backslashes to keep JSON valid&#13;&#10;fts.WriteLine( &quot;  \&quot;userPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;\&quot;&quot; );&#13;&#10;fts.WriteLine( &quot;}&quot; );&#13;&#10;&#13;&#10;fts.Close();&#13;&#10;&#13;&#10;// Make copy&#13;&#10;fso.CopyFile(dataFolder + &quot;settings.json&quot;, dataFolder + &quot;settings-orig.json&quot;, true); // overwrite&#13;&#10;&#13;&#10;// Rewrite settings.json to update repository path&#13;&#10;var fin = fso.OpenTextFile(dataFolder + &quot;settings-orig.json&quot;, ForReading, false);&#13;&#10;var fout = fso.OpenTextFile(dataFolder + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;// First line should contain opening brace&#13;&#10;fout.WriteLine( fin.ReadLine() );&#13;&#10;&#13;&#10;// Append our entries&#13;&#10;fout.WriteLine( &quot;  \&quot;repositoryPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;db\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;dataPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;data\&quot;,&quot; );&#13;&#10;&#13;&#10;// copy rest of settings&#13;&#10;while( !fin.AtEndOfStream ) {&#13;&#10;&#9;fout.WriteLine( fin.ReadLine() );&#13;&#10;}&#13;&#10;&#13;&#10;fin.Close();&#13;&#10;fout.Close();&#13;&#10;" AdditionalSeq="AI_DATA_SETTER_3"/>
+    <ROW Action="CustomizeSettingsJsonScript" Type="3109" Target="Script Text" TargetUnformatted="var actionData = Session.Property(&quot;CustomActionData&quot;);&#13;&#10;var actionDataArray = actionData.split(&quot;|&quot;);&#13;&#10;var appDir = actionDataArray[0];&#13;&#10;var dataFolder = actionDataArray[1] + actionDataArray[2] + &quot;\\&quot;;&#13;&#10;&#13;&#10;var ForReading = 1, ForWriting = 2, ForAppending = 8;&#13;&#10;var fso = new ActiveXObject(&quot;Scripting.FileSystemObject&quot;);&#13;&#10;&#13;&#10;// Create basic %APPDIR%\settings.json with path to real settings.json in dataFolder&#13;&#10;var fts = fso.OpenTextFile(appDir + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;fts.WriteLine( &quot;{&quot; );&#13;&#10;// We need to escape Windows path backslashes to keep JSON valid&#13;&#10;fts.WriteLine( &quot;  \&quot;userPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;\&quot;&quot; );&#13;&#10;fts.WriteLine( &quot;}&quot; );&#13;&#10;&#13;&#10;fts.Close();&#13;&#10;&#13;&#10;// Make copy&#13;&#10;fso.CopyFile(dataFolder + &quot;settings.json&quot;, dataFolder + &quot;settings-orig.json&quot;, true); // overwrite&#13;&#10;&#13;&#10;// Rewrite settings.json to update repository path&#13;&#10;var fin = fso.OpenTextFile(dataFolder + &quot;settings-orig.json&quot;, ForReading, false);&#13;&#10;var fout = fso.OpenTextFile(dataFolder + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;// First line should contain opening brace&#13;&#10;fout.WriteLine( fin.ReadLine() );&#13;&#10;&#13;&#10;// Append our entries&#13;&#10;fout.WriteLine( &quot;  \&quot;repositoryPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;db\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;dataPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;data\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;walletsPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;wallets\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;listsPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;lists\&quot;,&quot; );&#13;&#10;&#13;&#10;// copy rest of settings&#13;&#10;while( !fin.AtEndOfStream ) {&#13;&#10;&#9;fout.WriteLine( fin.ReadLine() );&#13;&#10;}&#13;&#10;&#13;&#10;fin.Close();&#13;&#10;fout.Close();&#13;&#10;" AdditionalSeq="AI_DATA_SETTER_3"/>
     <ROW Action="DetectRunningProcess" Type="1" Source="aicustact.dll" Target="DetectProcess" Options="3" AdditionalSeq="AI_DATA_SETTER_8"/>
     <ROW Action="DetectW32Time" Type="1" Source="aicustact.dll" Target="DetectService" Options="3" AdditionalSeq="AI_DATA_SETTER_11"/>
     <ROW Action="NTP_config" Type="3090" Source="ntpcfg.bat"/>

lib/org/ciyam/AT/1.4.0/AT-1.4.0.pom

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>org.ciyam</groupId>
+  <artifactId>AT</artifactId>
+  <version>1.4.0</version>
+  <description>POM was created from install:install-file</description>
+</project>

lib/org/ciyam/AT/maven-metadata-local.xml

@@ -3,14 +3,15 @@
   <groupId>org.ciyam</groupId>
   <artifactId>AT</artifactId>
   <versioning>
-    <release>1.3.8</release>
+    <release>1.4.0</release>
     <versions>
       <version>1.3.4</version>
       <version>1.3.5</version>
       <version>1.3.6</version>
       <version>1.3.7</version>
       <version>1.3.8</version>
+      <version>1.4.0</version>
     </versions>
-    <lastUpdated>20200925114415</lastUpdated>
+    <lastUpdated>20221105114346</lastUpdated>
   </versioning>
 </metadata>

pom.xml

@@ -3,15 +3,15 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.qortal</groupId>
 	<artifactId>qortal</artifactId>
-	<version>3.3.6</version>
+	<version>4.2.2</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>${maven.build.timestamp}</build.timestamp>
-		<ciyam-at.version>1.3.8</ciyam-at.version>
+		<ciyam-at.version>1.4.0</ciyam-at.version>
 		<commons-net.version>3.6</commons-net.version>
 		<commons-text.version>1.8</commons-text.version>
 		<commons-io.version>2.6</commons-io.version>
@@ -34,6 +34,9 @@
 		<package-info-maven-plugin.version>1.1.0</package-info-maven-plugin.version>
 		<jsoup.version>1.13.1</jsoup.version>
 		<java-diff-utils.version>4.10</java-diff-utils.version>
+		<grpc.version>1.45.1</grpc.version>
+		<protobuf.version>3.19.4</protobuf.version>
+		<simplemagic.version>1.17</simplemagic.version>
 	</properties>
 	<build>
 		<sourceDirectory>src/main/java</sourceDirectory>
@@ -145,6 +148,7 @@
 										tagsSorter: "alpha",
 										operationsSorter:
 										"alpha",
+										validatorUrl: false,
 									</value>
 								</replacement>
 							</replacements>
@@ -302,6 +306,7 @@
 									implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
 									<mainClass>org.qortal.controller.Controller</mainClass>
 									<manifestEntries>
+										<Multi-Release>true</Multi-Release>
 										<Class-Path>. ..</Class-Path>
 									</manifestEntries>
 								</transformer>
@@ -705,5 +710,30 @@
 			<artifactId>java-diff-utils</artifactId>
 			<version>${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>
+		<dependency>
+			<groupId>com.j256.simplemagic</groupId>
+			<artifactId>simplemagic</artifactId>
+			<version>${simplemagic.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 {
@@ -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

@@ -211,7 +211,8 @@ public class Account {
 		if (level != null && level >= BlockChain.getInstance().getMinAccountLevelToMint())
 			return true;
 
-		if (Account.isFounder(accountData.getFlags()))
+		// Founders can always mint, unless they have a penalty
+		if (Account.isFounder(accountData.getFlags()) && accountData.getBlocksMintedPenalty() == 0)
 			return true;
 
 		return false;
@@ -222,6 +223,11 @@ public class Account {
 		return this.repository.getAccountRepository().getMintedBlockCount(this.address);
 	}
 
+	/** Returns account's blockMintedPenalty or null if account not found in repository. */
+	public Integer getBlocksMintedPenalty() throws DataException {
+		return this.repository.getAccountRepository().getBlocksMintedPenaltyCount(this.address);
+	}
+
 
 	/** Returns whether account can build reward-shares.
 	 * <p>
@@ -243,7 +249,7 @@ public class Account {
 		if (level != null && level >= BlockChain.getInstance().getMinAccountLevelToRewardShare())
 			return true;
 
-		if (Account.isFounder(accountData.getFlags()))
+		if (Account.isFounder(accountData.getFlags()) && accountData.getBlocksMintedPenalty() == 0)
 			return true;
 
 		return false;
@@ -271,7 +277,7 @@ public class Account {
 	/**
 	 * Returns 'effective' minting level, or zero if account does not exist/cannot mint.
 	 * <p>
-	 * For founder accounts, this returns "founderEffectiveMintingLevel" from blockchain config.
+	 * For founder accounts with no penalty, this returns "founderEffectiveMintingLevel" from blockchain config.
 	 * 
 	 * @return 0+
 	 * @throws DataException
@@ -281,7 +287,8 @@ public class Account {
 		if (accountData == null)
 			return 0;
 
-		if (Account.isFounder(accountData.getFlags()))
+		// Founders are assigned a different effective minting level, as long as they have no penalty
+		if (Account.isFounder(accountData.getFlags()) && accountData.getBlocksMintedPenalty() == 0)
 			return BlockChain.getInstance().getFounderEffectiveMintingLevel();
 
 		return accountData.getLevel();
@@ -289,8 +296,6 @@ public class Account {
 
 	/**
 	 * Returns 'effective' minting level, or zero if reward-share does not exist.
-	 * <p>
-	 * this is being used on src/main/java/org/qortal/api/resource/AddressesResource.java to fulfil the online accounts api call
 	 * 
 	 * @param repository
 	 * @param rewardSharePublicKey
@@ -309,7 +314,7 @@ public class Account {
 	/**
 	 * Returns 'effective' minting level, with a fix for the zero level.
 	 * <p>
-	 * For founder accounts, this returns "founderEffectiveMintingLevel" from blockchain config.
+	 * For founder accounts with no penalty, this returns "founderEffectiveMintingLevel" from blockchain config.
 	 *
 	 * @param repository
 	 * @param rewardSharePublicKey
@@ -322,7 +327,7 @@ public class Account {
 		if (rewardShareData == null)
 			return 0;
 
-		else if(!rewardShareData.getMinter().equals(rewardShareData.getRecipient()))//the minter is different than the recipient this means sponsorship
+		else if (!rewardShareData.getMinter().equals(rewardShareData.getRecipient())) // Sponsorship reward share
 			return 0;
 
 		Account rewardShareMinter = new Account(repository, rewardShareData.getMinter());

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/account/SelfSponsorshipAlgoV1.java

@@ -0,0 +1,367 @@
+package org.qortal.account;
+
+import org.qortal.api.resource.TransactionsResource;
+import org.qortal.asset.Asset;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.naming.NameData;
+import org.qortal.data.transaction.*;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.transaction.Transaction.TransactionType;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class SelfSponsorshipAlgoV1 {
+
+    private final Repository repository;
+    private final String address;
+    private final AccountData accountData;
+    private final long snapshotTimestamp;
+    private final boolean override;
+
+    private int registeredNameCount = 0;
+    private int suspiciousCount = 0;
+    private int suspiciousPercent = 0;
+    private int consolidationCount = 0;
+    private int bulkIssuanceCount = 0;
+    private int recentSponsorshipCount = 0;
+
+    private List<RewardShareTransactionData> sponsorshipRewardShares = new ArrayList<>();
+    private final Map<String, List<TransactionData>> paymentsByAddress = new HashMap<>();
+    private final Set<String> sponsees = new LinkedHashSet<>();
+    private Set<String> consolidatedAddresses = new LinkedHashSet<>();
+    private final Set<String> zeroTransactionAddreses = new LinkedHashSet<>();
+    private final Set<String> penaltyAddresses = new LinkedHashSet<>();
+
+    public SelfSponsorshipAlgoV1(Repository repository, String address, long snapshotTimestamp, boolean override) throws DataException {
+        this.repository = repository;
+        this.address = address;
+        this.accountData = this.repository.getAccountRepository().getAccount(this.address);
+        this.snapshotTimestamp = snapshotTimestamp;
+        this.override = override;
+    }
+
+    public String getAddress() {
+        return this.address;
+    }
+
+    public Set<String> getPenaltyAddresses() {
+        return this.penaltyAddresses;
+    }
+
+
+    public void run() throws DataException {
+        if (this.accountData == null) {
+            // Nothing to do
+            return;
+        }
+
+        this.fetchSponsorshipRewardShares();
+        if (this.sponsorshipRewardShares.isEmpty()) {
+            // Nothing to do
+            return;
+        }
+
+        this.findConsolidatedRewards();
+        this.findBulkIssuance();
+        this.findRegisteredNameCount();
+        this.findRecentSponsorshipCount();
+
+        int score = this.calculateScore();
+        if (score <= 0 && !override) {
+            return;
+        }
+
+        String newAddress = this.getDestinationAccount(this.address);
+        while (newAddress != null) {
+            // Found destination account
+            this.penaltyAddresses.add(newAddress);
+
+            // Run algo for this address, but in "override" mode because it has already been flagged
+            SelfSponsorshipAlgoV1 algoV1 = new SelfSponsorshipAlgoV1(this.repository, newAddress, this.snapshotTimestamp, true);
+            algoV1.run();
+            this.penaltyAddresses.addAll(algoV1.getPenaltyAddresses());
+
+            newAddress = this.getDestinationAccount(newAddress);
+        }
+
+        this.penaltyAddresses.add(this.address);
+
+        if (this.override || this.recentSponsorshipCount < 20) {
+            this.penaltyAddresses.addAll(this.consolidatedAddresses);
+            this.penaltyAddresses.addAll(this.zeroTransactionAddreses);
+        }
+        else {
+            this.penaltyAddresses.addAll(this.sponsees);
+        }
+    }
+
+    private String getDestinationAccount(String address) throws DataException {
+        List<TransactionData> transferPrivsTransactions = fetchTransferPrivsForAddress(address);
+        if (transferPrivsTransactions.isEmpty()) {
+            // No TRANSFER_PRIVS transactions for this address
+            return null;
+        }
+
+        AccountData accountData = this.repository.getAccountRepository().getAccount(address);
+        if (accountData == null) {
+            return null;
+        }
+
+        for (TransactionData transactionData : transferPrivsTransactions) {
+            TransferPrivsTransactionData transferPrivsTransactionData = (TransferPrivsTransactionData) transactionData;
+            if (Arrays.equals(transferPrivsTransactionData.getSenderPublicKey(), accountData.getPublicKey())) {
+                return transferPrivsTransactionData.getRecipient();
+            }
+        }
+
+        return null;
+    }
+
+    private void findConsolidatedRewards() throws DataException {
+        List<String> sponseesThatSentRewards = new ArrayList<>();
+        Map<String, Integer> paymentRecipients = new HashMap<>();
+
+        // Collect outgoing payments of each sponsee
+        for (String sponseeAddress : this.sponsees) {
+
+            // Firstly fetch all payments for address, since the functions below depend on this data
+            this.fetchPaymentsForAddress(sponseeAddress);
+
+            // Check if the address has zero relevant transactions
+            if (this.hasZeroTransactions(sponseeAddress)) {
+                this.zeroTransactionAddreses.add(sponseeAddress);
+            }
+
+            // Get payment recipients
+            List<String> allPaymentRecipients = this.fetchOutgoingPaymentRecipientsForAddress(sponseeAddress);
+            if (allPaymentRecipients.isEmpty()) {
+                continue;
+            }
+            sponseesThatSentRewards.add(sponseeAddress);
+
+            List<String> addressesPaidByThisSponsee = new ArrayList<>();
+            for (String paymentRecipient : allPaymentRecipients) {
+                if (addressesPaidByThisSponsee.contains(paymentRecipient)) {
+                    // We already tracked this association - don't allow multiple to stack up
+                    continue;
+                }
+                addressesPaidByThisSponsee.add(paymentRecipient);
+
+                // Increment count for this recipient, or initialize to 1 if not present
+                if (paymentRecipients.computeIfPresent(paymentRecipient, (k, v) -> v + 1) == null) {
+                    paymentRecipients.put(paymentRecipient, 1);
+                }
+            }
+
+        }
+
+        // Exclude addresses with a low number of payments
+        Map<String, Integer> filteredPaymentRecipients = paymentRecipients.entrySet().stream()
+                .filter(p -> p.getValue() != null && p.getValue() >= 10)
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+
+        // Now check how many sponsees have sent to this subset of addresses
+        Map<String, Integer> sponseesThatConsolidatedRewards = new HashMap<>();
+        for (String sponseeAddress : sponseesThatSentRewards) {
+            List<String> allPaymentRecipients = this.fetchOutgoingPaymentRecipientsForAddress(sponseeAddress);
+            // Remove any that aren't to one of the flagged recipients (i.e. consolidation)
+            allPaymentRecipients.removeIf(r -> !filteredPaymentRecipients.containsKey(r));
+
+            int count = allPaymentRecipients.size();
+            if (count == 0) {
+                continue;
+            }
+            if (sponseesThatConsolidatedRewards.computeIfPresent(sponseeAddress, (k, v) -> v + count) == null) {
+                sponseesThatConsolidatedRewards.put(sponseeAddress, count);
+            }
+        }
+
+        // Remove sponsees that have only sent a low number of payments to the filtered addresses
+        Map<String, Integer> filteredSponseesThatConsolidatedRewards = sponseesThatConsolidatedRewards.entrySet().stream()
+                .filter(p -> p.getValue() != null && p.getValue() >= 2)
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+
+        this.consolidationCount = sponseesThatConsolidatedRewards.size();
+        this.consolidatedAddresses = new LinkedHashSet<>(filteredSponseesThatConsolidatedRewards.keySet());
+        this.suspiciousCount = this.consolidationCount + this.zeroTransactionAddreses.size();
+        this.suspiciousPercent = (int)(this.suspiciousCount / (float) this.sponsees.size() * 100);
+    }
+
+    private void findBulkIssuance() {
+        Long lastTimestamp = null;
+        for (RewardShareTransactionData rewardShareTransactionData : sponsorshipRewardShares) {
+            long timestamp = rewardShareTransactionData.getTimestamp();
+            if (timestamp >= this.snapshotTimestamp) {
+                continue;
+            }
+
+            if (lastTimestamp != null) {
+                if (timestamp - lastTimestamp < 3*60*1000L) {
+                    this.bulkIssuanceCount++;
+                }
+            }
+            lastTimestamp = timestamp;
+        }
+    }
+
+    private void findRegisteredNameCount() throws DataException {
+        int registeredNameCount = 0;
+        for (String sponseeAddress : sponsees) {
+            List<NameData> names = repository.getNameRepository().getNamesByOwner(sponseeAddress);
+            for (NameData name : names) {
+                if (name.getRegistered() < this.snapshotTimestamp) {
+                    registeredNameCount++;
+                    break;
+                }
+            }
+        }
+        this.registeredNameCount = registeredNameCount;
+    }
+
+    private void findRecentSponsorshipCount() {
+        final long referenceTimestamp = this.snapshotTimestamp - (365 * 24 * 60 * 60 * 1000L);
+        int recentSponsorshipCount = 0;
+        for (RewardShareTransactionData rewardShare : sponsorshipRewardShares) {
+            if (rewardShare.getTimestamp() >= referenceTimestamp) {
+                recentSponsorshipCount++;
+            }
+        }
+        this.recentSponsorshipCount = recentSponsorshipCount;
+    }
+
+    private int calculateScore() {
+        final int suspiciousMultiplier = (this.suspiciousCount >= 100) ? this.suspiciousPercent : 1;
+        final int nameMultiplier = (this.sponsees.size() >= 50 && this.registeredNameCount == 0) ? 2 : 1;
+        final int consolidationMultiplier = Math.max(this.consolidationCount, 1);
+        final int bulkIssuanceMultiplier = Math.max(this.bulkIssuanceCount / 2, 1);
+        final int offset = 9;
+        return suspiciousMultiplier * nameMultiplier * consolidationMultiplier * bulkIssuanceMultiplier - offset;
+    }
+
+    private void fetchSponsorshipRewardShares() throws DataException {
+        List<RewardShareTransactionData> sponsorshipRewardShares = new ArrayList<>();
+
+        // Define relevant transactions
+        List<TransactionType> txTypes = List.of(TransactionType.REWARD_SHARE);
+        List<TransactionData> transactionDataList = fetchTransactions(repository, txTypes, this.address, false);
+
+        for (TransactionData transactionData : transactionDataList) {
+            if (transactionData.getType() != TransactionType.REWARD_SHARE) {
+                continue;
+            }
+
+            RewardShareTransactionData rewardShareTransactionData = (RewardShareTransactionData) transactionData;
+
+            // Skip removals
+            if (rewardShareTransactionData.getSharePercent() < 0) {
+                continue;
+            }
+
+            // Skip if not sponsored by this account
+            if (!Arrays.equals(rewardShareTransactionData.getCreatorPublicKey(), accountData.getPublicKey())) {
+                continue;
+            }
+
+            // Skip self shares
+            if (Objects.equals(rewardShareTransactionData.getRecipient(), this.address)) {
+                continue;
+            }
+
+            boolean duplicateFound = false;
+            for (RewardShareTransactionData existingRewardShare : sponsorshipRewardShares) {
+                if (Objects.equals(existingRewardShare.getRecipient(), rewardShareTransactionData.getRecipient())) {
+                    // Duplicate
+                    duplicateFound = true;
+                    break;
+                }
+            }
+            if (!duplicateFound) {
+                sponsorshipRewardShares.add(rewardShareTransactionData);
+                this.sponsees.add(rewardShareTransactionData.getRecipient());
+            }
+        }
+
+        this.sponsorshipRewardShares = sponsorshipRewardShares;
+    }
+
+    private List<TransactionData> fetchTransferPrivsForAddress(String address) throws DataException {
+        return fetchTransactions(repository,
+                List.of(TransactionType.TRANSFER_PRIVS),
+                address, true);
+    }
+
+    private void fetchPaymentsForAddress(String address) throws DataException {
+        List<TransactionData> payments = fetchTransactions(repository,
+                Arrays.asList(TransactionType.PAYMENT, TransactionType.TRANSFER_ASSET),
+                address, false);
+        this.paymentsByAddress.put(address, payments);
+    }
+
+    private List<String> fetchOutgoingPaymentRecipientsForAddress(String address) {
+        List<String> outgoingPaymentRecipients = new ArrayList<>();
+
+        List<TransactionData> transactionDataList = this.paymentsByAddress.get(address);
+        if (transactionDataList == null) transactionDataList = new ArrayList<>();
+        transactionDataList.removeIf(t -> t.getTimestamp() >= this.snapshotTimestamp);
+        for (TransactionData transactionData : transactionDataList) {
+            switch (transactionData.getType()) {
+
+                case PAYMENT:
+                    PaymentTransactionData paymentTransactionData = (PaymentTransactionData) transactionData;
+                    if (!Objects.equals(paymentTransactionData.getRecipient(), address)) {
+                        // Outgoing payment from this account
+                        outgoingPaymentRecipients.add(paymentTransactionData.getRecipient());
+                    }
+                    break;
+
+                case TRANSFER_ASSET:
+                    TransferAssetTransactionData transferAssetTransactionData = (TransferAssetTransactionData) transactionData;
+                    if (transferAssetTransactionData.getAssetId() == Asset.QORT) {
+                        if (!Objects.equals(transferAssetTransactionData.getRecipient(), address)) {
+                            // Outgoing payment from this account
+                            outgoingPaymentRecipients.add(transferAssetTransactionData.getRecipient());
+                        }
+                    }
+                    break;
+
+                default:
+                    break;
+            }
+        }
+
+        return outgoingPaymentRecipients;
+    }
+
+    private boolean hasZeroTransactions(String address) {
+        List<TransactionData> transactionDataList = this.paymentsByAddress.get(address);
+        if (transactionDataList == null) {
+            return true;
+        }
+        transactionDataList.removeIf(t -> t.getTimestamp() >= this.snapshotTimestamp);
+        return transactionDataList.size() == 0;
+    }
+
+    private static List<TransactionData> fetchTransactions(Repository repository, List<TransactionType> txTypes, String address, boolean reverse) throws DataException {
+        // Fetch all relevant transactions for this account
+        List<byte[]> signatures = repository.getTransactionRepository()
+                .getSignaturesMatchingCriteria(null, null, null, txTypes,
+                        null, null, address, TransactionsResource.ConfirmationStatus.CONFIRMED,
+                        null, null, reverse);
+
+        List<TransactionData> transactionDataList = new ArrayList<>();
+
+        for (byte[] signature : signatures) {
+            // Fetch transaction data
+            TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
+            if (transactionData == null) {
+                continue;
+            }
+            transactionDataList.add(transactionData);
+        }
+
+        return transactionDataList;
+    }
+
+}

src/main/java/org/qortal/api/ApiError.java

@@ -79,7 +79,7 @@ public enum ApiError {
 	// BUYER_ALREADY_OWNER(411, 422),
 
 	// POLLS
-	// POLL_NO_EXISTS(501, 404),
+	POLL_NO_EXISTS(501, 404),
 	// POLL_ALREADY_EXISTS(502, 422),
 	// DUPLICATE_OPTION(503, 422),
 	// POLL_OPTION_NO_EXISTS(504, 404),

src/main/java/org/qortal/api/ApiRequest.java

@@ -3,6 +3,7 @@ package org.qortal.api;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.UnsupportedEncodingException;
+import java.io.Writer;
 import java.net.HttpURLConnection;
 import java.net.InetSocketAddress;
 import java.net.Socket;
@@ -20,14 +21,12 @@ import javax.net.ssl.SNIHostName;
 import javax.net.ssl.SNIServerName;
 import javax.net.ssl.SSLParameters;
 import javax.net.ssl.SSLSocket;
-import javax.xml.bind.JAXBContext;
-import javax.xml.bind.JAXBException;
-import javax.xml.bind.UnmarshalException;
-import javax.xml.bind.Unmarshaller;
+import javax.xml.bind.*;
 import javax.xml.transform.stream.StreamSource;
 
 import org.eclipse.persistence.exceptions.XMLMarshalException;
 import org.eclipse.persistence.jaxb.JAXBContextFactory;
+import org.eclipse.persistence.jaxb.MarshallerProperties;
 import org.eclipse.persistence.jaxb.UnmarshallerProperties;
 
 public class ApiRequest {
@@ -107,6 +106,36 @@ public class ApiRequest {
 		}
 	}
 
+	private static Marshaller createMarshaller(Class<?> objectClass) {
+		try {
+			// Create JAXB context aware of object's class
+			JAXBContext jc = JAXBContextFactory.createContext(new Class[] { objectClass }, null);
+
+			// Create marshaller
+			Marshaller marshaller = jc.createMarshaller();
+
+			// Set the marshaller media type to JSON
+			marshaller.setProperty(MarshallerProperties.MEDIA_TYPE, "application/json");
+
+			// Tell marshaller not to include JSON root element in the output
+			marshaller.setProperty(MarshallerProperties.JSON_INCLUDE_ROOT, false);
+
+			return marshaller;
+		} catch (JAXBException e) {
+			throw new RuntimeException("Unable to create API marshaller", e);
+		}
+	}
+
+	public static void marshall(Writer writer, Object object) throws IOException {
+		Marshaller marshaller = createMarshaller(object.getClass());
+
+		try {
+			marshaller.marshal(object, writer);
+		} catch (JAXBException e) {
+			throw new IOException("Unable to create marshall object for API", e);
+		}
+	}
+
 	public static String getParamsString(Map<String, String> params) {
 		StringBuilder result = new StringBuilder();
 

src/main/java/org/qortal/api/ApiService.java

@@ -13,8 +13,8 @@ import java.security.SecureRandom;
 
 import javax.net.ssl.KeyManagerFactory;
 import javax.net.ssl.SSLContext;
+import javax.servlet.http.HttpServletRequest;
 
-import org.checkerframework.checker.units.qual.A;
 import org.eclipse.jetty.http.HttpVersion;
 import org.eclipse.jetty.rewrite.handler.RedirectPatternRule;
 import org.eclipse.jetty.rewrite.handler.RewriteHandler;
@@ -41,6 +41,7 @@ import org.glassfish.jersey.servlet.ServletContainer;
 import org.qortal.api.resource.AnnotationPostProcessor;
 import org.qortal.api.resource.ApiDefinition;
 import org.qortal.api.websocket.*;
+import org.qortal.network.Network;
 import org.qortal.settings.Settings;
 
 public class ApiService {
@@ -51,9 +52,11 @@ public class ApiService {
 	private Server server;
 	private ApiKey apiKey;
 
+	public static final String API_VERSION_HEADER = "X-API-VERSION";
+
 	private ApiService() {
 		this.config = new ResourceConfig();
-		this.config.packages("org.qortal.api.resource");
+		this.config.packages("org.qortal.api.resource", "org.qortal.api.restricted.resource");
 		this.config.register(OpenApiResource.class);
 		this.config.register(ApiDefinition.class);
 		this.config.register(AnnotationPostProcessor.class);
@@ -93,7 +96,7 @@ public class ApiService {
 					throw new RuntimeException("Failed to start SSL API due to broken keystore");
 
 				// BouncyCastle-specific SSLContext build
-				SSLContext sslContext = SSLContext.getInstance("TLS", "BCJSSE");
+				SSLContext sslContext = SSLContext.getInstance("TLSv1.3", "BCJSSE");
 				KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("PKIX", "BCJSSE");
 
 				KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType(), "BC");
@@ -123,13 +126,13 @@ public class ApiService {
 				ServerConnector portUnifiedConnector = new ServerConnector(this.server,
 						new DetectorConnectionFactory(sslConnectionFactory),
 						httpConnectionFactory);
-				portUnifiedConnector.setHost(Settings.getInstance().getBindAddress());
+				portUnifiedConnector.setHost(Network.getInstance().getBindAddress());
 				portUnifiedConnector.setPort(Settings.getInstance().getApiPort());
 
 				this.server.addConnector(portUnifiedConnector);
 			} else {
 				// Non-SSL
-				InetAddress bindAddr = InetAddress.getByName(Settings.getInstance().getBindAddress());
+				InetAddress bindAddr = InetAddress.getByName(Network.getInstance().getBindAddress());
 				InetSocketAddress endpoint = new InetSocketAddress(bindAddr, Settings.getInstance().getApiPort());
 				this.server = new Server(endpoint);
 			}
@@ -230,4 +233,19 @@ public class ApiService {
 		this.server = null;
 	}
 
+	public static int getApiVersion(HttpServletRequest request) {
+		// Get API version
+		String apiVersionString = request.getHeader(API_VERSION_HEADER);
+		if (apiVersionString == null) {
+			// Try query string - this is needed to avoid a CORS preflight. See: https://stackoverflow.com/a/43881141
+			apiVersionString = request.getParameter("apiVersion");
+		}
+
+		int apiVersion = 1;
+		if (apiVersionString != null) {
+			apiVersion = Integer.parseInt(apiVersionString);
+		}
+		return apiVersion;
+	}
+
 }

src/main/java/org/qortal/api/DevProxyService.java

@@ -0,0 +1,173 @@
+package org.qortal.api;
+
+import io.swagger.v3.jaxrs2.integration.resources.OpenApiResource;
+import org.eclipse.jetty.http.HttpVersion;
+import org.eclipse.jetty.rewrite.handler.RewriteHandler;
+import org.eclipse.jetty.server.*;
+import org.eclipse.jetty.server.handler.ErrorHandler;
+import org.eclipse.jetty.server.handler.InetAccessHandler;
+import org.eclipse.jetty.servlet.FilterHolder;
+import org.eclipse.jetty.servlet.ServletContextHandler;
+import org.eclipse.jetty.servlet.ServletHolder;
+import org.eclipse.jetty.servlets.CrossOriginFilter;
+import org.eclipse.jetty.util.ssl.SslContextFactory;
+import org.glassfish.jersey.server.ResourceConfig;
+import org.glassfish.jersey.servlet.ServletContainer;
+import org.qortal.api.resource.AnnotationPostProcessor;
+import org.qortal.api.resource.ApiDefinition;
+import org.qortal.network.Network;
+import org.qortal.repository.DataException;
+import org.qortal.settings.Settings;
+
+import javax.net.ssl.KeyManagerFactory;
+import javax.net.ssl.SSLContext;
+import java.io.InputStream;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.security.KeyStore;
+import java.security.SecureRandom;
+
+public class DevProxyService {
+
+	private static DevProxyService instance;
+
+	private final ResourceConfig config;
+	private Server server;
+
+	private DevProxyService() {
+		this.config = new ResourceConfig();
+		this.config.packages("org.qortal.api.proxy.resource", "org.qortal.api.resource");
+		this.config.register(OpenApiResource.class);
+		this.config.register(ApiDefinition.class);
+		this.config.register(AnnotationPostProcessor.class);
+	}
+
+	public static DevProxyService getInstance() {
+		if (instance == null)
+			instance = new DevProxyService();
+
+		return instance;
+	}
+
+	public Iterable<Class<?>> getResources() {
+		return this.config.getClasses();
+	}
+
+	public void start() throws DataException {
+		try {
+			// Create API server
+
+			// SSL support if requested
+			String keystorePathname = Settings.getInstance().getSslKeystorePathname();
+			String keystorePassword = Settings.getInstance().getSslKeystorePassword();
+
+			if (keystorePathname != null && keystorePassword != null) {
+				// SSL version
+				if (!Files.isReadable(Path.of(keystorePathname)))
+					throw new RuntimeException("Failed to start SSL API due to broken keystore");
+
+				// BouncyCastle-specific SSLContext build
+				SSLContext sslContext = SSLContext.getInstance("TLS", "BCJSSE");
+				KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("PKIX", "BCJSSE");
+
+				KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType(), "BC");
+
+				try (InputStream keystoreStream = Files.newInputStream(Paths.get(keystorePathname))) {
+					keyStore.load(keystoreStream, keystorePassword.toCharArray());
+				}
+
+				keyManagerFactory.init(keyStore, keystorePassword.toCharArray());
+				sslContext.init(keyManagerFactory.getKeyManagers(), null, new SecureRandom());
+
+				SslContextFactory.Server sslContextFactory = new SslContextFactory.Server();
+				sslContextFactory.setSslContext(sslContext);
+
+				this.server = new Server();
+
+				HttpConfiguration httpConfig = new HttpConfiguration();
+				httpConfig.setSecureScheme("https");
+				httpConfig.setSecurePort(Settings.getInstance().getDevProxyPort());
+
+				SecureRequestCustomizer src = new SecureRequestCustomizer();
+				httpConfig.addCustomizer(src);
+
+				HttpConnectionFactory httpConnectionFactory = new HttpConnectionFactory(httpConfig);
+				SslConnectionFactory sslConnectionFactory = new SslConnectionFactory(sslContextFactory, HttpVersion.HTTP_1_1.asString());
+
+				ServerConnector portUnifiedConnector = new ServerConnector(this.server,
+						new DetectorConnectionFactory(sslConnectionFactory),
+						httpConnectionFactory);
+				portUnifiedConnector.setHost(Network.getInstance().getBindAddress());
+				portUnifiedConnector.setPort(Settings.getInstance().getDevProxyPort());
+
+				this.server.addConnector(portUnifiedConnector);
+			} else {
+				// Non-SSL
+				InetAddress bindAddr = InetAddress.getByName(Network.getInstance().getBindAddress());
+				InetSocketAddress endpoint = new InetSocketAddress(bindAddr, Settings.getInstance().getDevProxyPort());
+				this.server = new Server(endpoint);
+			}
+
+			// Error handler
+			ErrorHandler errorHandler = new ApiErrorHandler();
+			this.server.setErrorHandler(errorHandler);
+
+			// Request logging
+			if (Settings.getInstance().isDevProxyLoggingEnabled()) {
+				RequestLogWriter logWriter = new RequestLogWriter("devproxy-requests.log");
+				logWriter.setAppend(true);
+				logWriter.setTimeZone("UTC");
+				RequestLog requestLog = new CustomRequestLog(logWriter, CustomRequestLog.EXTENDED_NCSA_FORMAT);
+				this.server.setRequestLog(requestLog);
+			}
+
+			// Access handler (currently no whitelist is used)
+			InetAccessHandler accessHandler = new InetAccessHandler();
+			this.server.setHandler(accessHandler);
+
+			// URL rewriting
+			RewriteHandler rewriteHandler = new RewriteHandler();
+			accessHandler.setHandler(rewriteHandler);
+
+			// Context
+			ServletContextHandler context = new ServletContextHandler(ServletContextHandler.NO_SESSIONS);
+			context.setContextPath("/");
+			rewriteHandler.setHandler(context);
+
+			// Cross-origin resource sharing
+			FilterHolder corsFilterHolder = new FilterHolder(CrossOriginFilter.class);
+			corsFilterHolder.setInitParameter(CrossOriginFilter.ALLOWED_ORIGINS_PARAM, "*");
+			corsFilterHolder.setInitParameter(CrossOriginFilter.ALLOWED_METHODS_PARAM, "GET, POST, DELETE");
+			corsFilterHolder.setInitParameter(CrossOriginFilter.CHAIN_PREFLIGHT_PARAM, "false");
+			context.addFilter(corsFilterHolder, "/*", null);
+
+			// API servlet
+			ServletContainer container = new ServletContainer(this.config);
+			ServletHolder apiServlet = new ServletHolder(container);
+			apiServlet.setInitOrder(1);
+			context.addServlet(apiServlet, "/*");
+
+			// Start server
+			this.server.start();
+		} catch (Exception e) {
+			// Failed to start
+			throw new DataException("Failed to start developer proxy", e);
+		}
+	}
+
+	public void stop() {
+		try {
+			// Stop server
+			this.server.stop();
+		} catch (Exception e) {
+			// Failed to stop
+		}
+
+		this.server = null;
+		instance = null;
+	}
+
+}

src/main/java/org/qortal/api/DomainMapService.java

@@ -3,7 +3,6 @@ package org.qortal.api;
 import io.swagger.v3.jaxrs2.integration.resources.OpenApiResource;
 import org.eclipse.jetty.http.HttpVersion;
 import org.eclipse.jetty.rewrite.handler.RewriteHandler;
-import org.eclipse.jetty.rewrite.handler.RewritePatternRule;
 import org.eclipse.jetty.server.*;
 import org.eclipse.jetty.server.handler.ErrorHandler;
 import org.eclipse.jetty.server.handler.InetAccessHandler;
@@ -16,6 +15,7 @@ import org.glassfish.jersey.server.ResourceConfig;
 import org.glassfish.jersey.servlet.ServletContainer;
 import org.qortal.api.resource.AnnotationPostProcessor;
 import org.qortal.api.resource.ApiDefinition;
+import org.qortal.network.Network;
 import org.qortal.settings.Settings;
 
 import javax.net.ssl.KeyManagerFactory;
@@ -38,7 +38,7 @@ public class DomainMapService {
 
 	private DomainMapService() {
 		this.config = new ResourceConfig();
-		this.config.packages("org.qortal.api.domainmap.resource");
+		this.config.packages("org.qortal.api.resource", "org.qortal.api.domainmap.resource");
 		this.config.register(OpenApiResource.class);
 		this.config.register(ApiDefinition.class);
 		this.config.register(AnnotationPostProcessor.class);
@@ -69,7 +69,7 @@ public class DomainMapService {
 					throw new RuntimeException("Failed to start SSL API due to broken keystore");
 
 				// BouncyCastle-specific SSLContext build
-				SSLContext sslContext = SSLContext.getInstance("TLS", "BCJSSE");
+				SSLContext sslContext = SSLContext.getInstance("TLSv1.3", "BCJSSE");
 				KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("PKIX", "BCJSSE");
 
 				KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType(), "BC");
@@ -99,13 +99,13 @@ public class DomainMapService {
 				ServerConnector portUnifiedConnector = new ServerConnector(this.server,
 						new DetectorConnectionFactory(sslConnectionFactory),
 						httpConnectionFactory);
-				portUnifiedConnector.setHost(Settings.getInstance().getBindAddress());
+				portUnifiedConnector.setHost(Network.getInstance().getBindAddress());
 				portUnifiedConnector.setPort(Settings.getInstance().getDomainMapPort());
 
 				this.server.addConnector(portUnifiedConnector);
 			} else {
 				// Non-SSL
-				InetAddress bindAddr = InetAddress.getByName(Settings.getInstance().getBindAddress());
+				InetAddress bindAddr = InetAddress.getByName(Network.getInstance().getBindAddress());
 				InetSocketAddress endpoint = new InetSocketAddress(bindAddr, Settings.getInstance().getDomainMapPort());
 				this.server = new Server(endpoint);
 			}

src/main/java/org/qortal/api/GatewayService.java

@@ -15,6 +15,7 @@ import org.glassfish.jersey.server.ResourceConfig;
 import org.glassfish.jersey.servlet.ServletContainer;
 import org.qortal.api.resource.AnnotationPostProcessor;
 import org.qortal.api.resource.ApiDefinition;
+import org.qortal.network.Network;
 import org.qortal.settings.Settings;
 
 import javax.net.ssl.KeyManagerFactory;
@@ -37,7 +38,7 @@ public class GatewayService {
 
 	private GatewayService() {
 		this.config = new ResourceConfig();
-		this.config.packages("org.qortal.api.gateway.resource");
+		this.config.packages("org.qortal.api.resource", "org.qortal.api.gateway.resource");
 		this.config.register(OpenApiResource.class);
 		this.config.register(ApiDefinition.class);
 		this.config.register(AnnotationPostProcessor.class);
@@ -68,7 +69,7 @@ public class GatewayService {
 					throw new RuntimeException("Failed to start SSL API due to broken keystore");
 
 				// BouncyCastle-specific SSLContext build
-				SSLContext sslContext = SSLContext.getInstance("TLS", "BCJSSE");
+				SSLContext sslContext = SSLContext.getInstance("TLSv1.3", "BCJSSE");
 				KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("PKIX", "BCJSSE");
 
 				KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType(), "BC");
@@ -98,13 +99,13 @@ public class GatewayService {
 				ServerConnector portUnifiedConnector = new ServerConnector(this.server,
 						new DetectorConnectionFactory(sslConnectionFactory),
 						httpConnectionFactory);
-				portUnifiedConnector.setHost(Settings.getInstance().getBindAddress());
+				portUnifiedConnector.setHost(Network.getInstance().getBindAddress());
 				portUnifiedConnector.setPort(Settings.getInstance().getGatewayPort());
 
 				this.server.addConnector(portUnifiedConnector);
 			} else {
 				// Non-SSL
-				InetAddress bindAddr = InetAddress.getByName(Settings.getInstance().getBindAddress());
+				InetAddress bindAddr = InetAddress.getByName(Network.getInstance().getBindAddress());
 				InetSocketAddress endpoint = new InetSocketAddress(bindAddr, Settings.getInstance().getGatewayPort());
 				this.server = new Server(endpoint);
 			}

src/main/java/org/qortal/api/HTMLParser.java

@@ -5,28 +5,71 @@ import org.apache.logging.log4j.Logger;
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
 import org.jsoup.select.Elements;
+import org.qortal.arbitrary.misc.Service;
+
+import java.util.Objects;
 
 public class HTMLParser {
 
     private static final Logger LOGGER = LogManager.getLogger(HTMLParser.class);
 
-    private String linkPrefix;
+    private String qdnBase;
+    private String qdnBaseWithPath;
     private byte[] data;
+    private String qdnContext;
+    private String resourceId;
+    private Service service;
+    private String identifier;
+    private String path;
+    private String theme;
+    private boolean usingCustomRouting;
 
-    public HTMLParser(String resourceId, String inPath, String prefix, boolean usePrefix, byte[] data) {
-        String inPathWithoutFilename = inPath.substring(0, inPath.lastIndexOf('/'));
-        this.linkPrefix = usePrefix ? String.format("%s/%s%s", prefix, resourceId, inPathWithoutFilename) : "";
+    public HTMLParser(String resourceId, String inPath, String prefix, boolean includeResourceIdInPrefix, byte[] data,
+                      String qdnContext, Service service, String identifier, String theme, boolean usingCustomRouting) {
+        String inPathWithoutFilename = inPath.contains("/") ? inPath.substring(0, inPath.lastIndexOf('/')) : String.format("/%s",inPath);
+        this.qdnBase = includeResourceIdInPrefix ? String.format("%s/%s", prefix, resourceId) : prefix;
+        this.qdnBaseWithPath = includeResourceIdInPrefix ? String.format("%s/%s%s", prefix, resourceId, inPathWithoutFilename) : String.format("%s%s", prefix, inPathWithoutFilename);
         this.data = data;
+        this.qdnContext = qdnContext;
+        this.resourceId = resourceId;
+        this.service = service;
+        this.identifier = identifier;
+        this.path = inPath;
+        this.theme = theme;
+        this.usingCustomRouting = usingCustomRouting;
     }
 
     public void addAdditionalHeaderTags() {
         String fileContents = new String(data);
         Document document = Jsoup.parse(fileContents);
-        String baseUrl = this.linkPrefix + "/";
         Elements head = document.getElementsByTag("head");
         if (!head.isEmpty()) {
+            // Add q-apps script tag
+            String qAppsScriptElement = String.format("<script src=\"/apps/q-apps.js?time=%d\">", System.currentTimeMillis());
+            head.get(0).prepend(qAppsScriptElement);
+
+            // Add q-apps gateway script tag if in gateway mode
+            if (Objects.equals(this.qdnContext, "gateway")) {
+                String qAppsGatewayScriptElement = String.format("<script src=\"/apps/q-apps-gateway.js?time=%d\">", System.currentTimeMillis());
+                head.get(0).prepend(qAppsGatewayScriptElement);
+            }
+
+            // Escape and add vars
+            String qdnContext = this.qdnContext != null ? this.qdnContext.replace("\\", "").replace("\"","\\\"") : "";
+            String service = this.service.toString().replace("\\", "").replace("\"","\\\"");
+            String name = this.resourceId != null ? this.resourceId.replace("\\", "").replace("\"","\\\"") : "";
+            String identifier = this.identifier != null ? this.identifier.replace("\\", "").replace("\"","\\\"") : "";
+            String path = this.path != null ? this.path.replace("\\", "").replace("\"","\\\"") : "";
+            String theme = this.theme != null ? this.theme.replace("\\", "").replace("\"","\\\"") : "";
+            String qdnBase = this.qdnBase != null ? this.qdnBase.replace("\\", "").replace("\"","\\\"") : "";
+            String qdnBaseWithPath = this.qdnBaseWithPath != null ? this.qdnBaseWithPath.replace("\\", "").replace("\"","\\\"") : "";
+            String qdnContextVar = String.format("<script>var _qdnContext=\"%s\"; var _qdnTheme=\"%s\"; var _qdnService=\"%s\"; var _qdnName=\"%s\"; var _qdnIdentifier=\"%s\"; var _qdnPath=\"%s\"; var _qdnBase=\"%s\"; var _qdnBaseWithPath=\"%s\";</script>", qdnContext, theme, service, name, identifier, path, qdnBase, qdnBaseWithPath);
+            head.get(0).prepend(qdnContextVar);
+
             // Add base href tag
-            String baseElement = String.format("<base href=\"%s\">", baseUrl);
+            // Exclude the path if this request was routed back to the index automatically
+            String baseHref = this.usingCustomRouting ? this.qdnBase : this.qdnBaseWithPath;
+            String baseElement = String.format("<base href=\"%s/\">", baseHref);
             head.get(0).prepend(baseElement);
 
             // Add meta charset tag
@@ -39,7 +82,7 @@ public class HTMLParser {
     }
 
     public static boolean isHtmlFile(String path) {
-        if (path.endsWith(".html") || path.endsWith(".htm")) {
+        if (path.endsWith(".html") || path.endsWith(".htm") || path.equals("")) {
             return true;
         }
         return false;

src/main/java/org/qortal/api/SearchMode.java

@@ -0,0 +1,6 @@
+package org.qortal.api;
+
+public enum SearchMode {
+    LATEST,
+    ALL;
+}

src/main/java/org/qortal/api/Security.java

@@ -15,7 +15,21 @@ public abstract class Security {
 
 	public static final String API_KEY_HEADER = "X-API-KEY";
 
+	/**
+	 * Check API call is allowed, retrieving the API key from the request header or GET/POST parameters where required
+	 * @param request
+	 */
 	public static void checkApiCallAllowed(HttpServletRequest request) {
+		checkApiCallAllowed(request, null);
+	}
+
+	/**
+	 * Check API call is allowed, retrieving the API key first from the passedApiKey parameter, with a fallback
+	 * to the request header or GET/POST parameters when null.
+	 * @param request
+	 * @param passedApiKey - the API key to test, or null if it should be retrieved from the request headers.
+	 */
+	public static void checkApiCallAllowed(HttpServletRequest request, String passedApiKey) {
 		// We may want to allow automatic authentication for local requests, if enabled in settings
 		boolean localAuthBypassEnabled = Settings.getInstance().isLocalAuthBypassEnabled();
 		if (localAuthBypassEnabled) {
@@ -38,7 +52,10 @@ public abstract class Security {
 		}
 
 		// We require an API key to be passed
-		String passedApiKey = request.getHeader(API_KEY_HEADER);
+		if (passedApiKey == null) {
+			// API call not passed as a parameter, so try the header
+			passedApiKey = request.getHeader(API_KEY_HEADER);
+		}
 		if (passedApiKey == null) {
 			// Try query string - this is needed to avoid a CORS preflight. See: https://stackoverflow.com/a/43881141
 			passedApiKey = request.getParameter("apiKey");
@@ -56,7 +73,7 @@ public abstract class Security {
 	public static void disallowLoopbackRequests(HttpServletRequest request) {
 		try {
 			InetAddress remoteAddr = InetAddress.getByName(request.getRemoteAddr());
-			if (remoteAddr.isLoopbackAddress()) {
+			if (remoteAddr.isLoopbackAddress() && !Settings.getInstance().isGatewayLoopbackEnabled()) {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.UNAUTHORIZED, "Local requests not allowed");
 			}
 		} catch (UnknownHostException e) {
@@ -84,9 +101,9 @@ public abstract class Security {
 		}
 	}
 
-	public static void requirePriorAuthorizationOrApiKey(HttpServletRequest request, String resourceId, Service service, String identifier) {
+	public static void requirePriorAuthorizationOrApiKey(HttpServletRequest request, String resourceId, Service service, String identifier, String apiKey) {
 		try {
-			Security.checkApiCallAllowed(request);
+			Security.checkApiCallAllowed(request, apiKey);
 
 		} catch (ApiException e) {
 			// API call wasn't allowed, but maybe it was pre-authorized

src/main/java/org/qortal/api/domainmap/resource/DomainMapResource.java

@@ -42,16 +42,16 @@ public class DomainMapResource {
             // Build synchronously, so that we don't need to make the summary API endpoints available over
             // the domain map server. This means that there will be no loading screen, but this is potentially
             // preferred in this situation anyway (e.g. to avoid confusing search engine robots).
-            return this.get(domainMap.get(request.getServerName()), ResourceIdType.NAME, Service.WEBSITE, inPath, null, "", false, false);
+            return this.get(domainMap.get(request.getServerName()), ResourceIdType.NAME, Service.WEBSITE, null, inPath, null, "", false, false);
         }
         return ArbitraryDataRenderer.getResponse(response, 404, "Error 404: File Not Found");
     }
 
-    private HttpServletResponse get(String resourceId, ResourceIdType resourceIdType, Service service, String inPath,
-                                    String secret58, String prefix, boolean usePrefix, boolean async) {
+    private HttpServletResponse get(String resourceId, ResourceIdType resourceIdType, Service service, String identifier,
+                                    String inPath, String secret58, String prefix, boolean includeResourceIdInPrefix, boolean async) {
 
-        ArbitraryDataRenderer renderer = new ArbitraryDataRenderer(resourceId, resourceIdType, service, inPath,
-                secret58, prefix, usePrefix, async, request, response, context);
+        ArbitraryDataRenderer renderer = new ArbitraryDataRenderer(resourceId, resourceIdType, service, identifier, inPath,
+                secret58, prefix, includeResourceIdInPrefix, async, "domainMap", request, response, context);
         return renderer.render();
     }
 

src/main/java/org/qortal/api/gateway/resource/GatewayResource.java

@@ -2,6 +2,9 @@ package org.qortal.api.gateway.resource;
 
 import io.swagger.v3.oas.annotations.security.SecurityRequirement;
 import io.swagger.v3.oas.annotations.tags.Tag;
+import org.apache.commons.lang3.StringUtils;
+import org.qortal.api.ApiError;
+import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.Security;
 import org.qortal.arbitrary.ArbitraryDataFile;
 import org.qortal.arbitrary.ArbitraryDataFile.ResourceIdType;
@@ -10,12 +13,19 @@ import org.qortal.arbitrary.ArbitraryDataRenderer;
 import org.qortal.arbitrary.ArbitraryDataResource;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.data.arbitrary.ArbitraryResourceStatus;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.repository.RepositoryManager;
 
 import javax.servlet.ServletContext;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.ws.rs.*;
 import javax.ws.rs.core.Context;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
 
 
 @Path("/")
@@ -26,36 +36,12 @@ public class GatewayResource {
     @Context HttpServletResponse response;
     @Context ServletContext context;
 
-    /**
-     * We need to allow resource status checking (and building) via the gateway, as the node's API port
-     * may not be forwarded and will almost certainly not be authenticated. Since gateways allow for
-     * all resources to be loaded except those that are blocked, there is no need for authentication.
-     */
-    @GET
-    @Path("/arbitrary/resource/status/{service}/{name}")
-    public ArbitraryResourceStatus getDefaultResourceStatus(@PathParam("service") Service service,
-                                                             @PathParam("name") String name,
-                                                             @QueryParam("build") Boolean build) {
-
-        return this.getStatus(service, name, null, build);
-    }
-
-    @GET
-    @Path("/arbitrary/resource/status/{service}/{name}/{identifier}")
-    public ArbitraryResourceStatus getResourceStatus(@PathParam("service") Service service,
-                                                      @PathParam("name") String name,
-                                                      @PathParam("identifier") String identifier,
-                                                      @QueryParam("build") Boolean build) {
-
-        return this.getStatus(service, name, identifier, build);
-    }
-
     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 {
+                ArbitraryDataReader reader = new ArbitraryDataReader(name, ArbitraryDataFile.ResourceIdType.NAME, service, null);
                 if (!reader.isBuilding()) {
                     reader.loadSynchronously(false);
                 }
@@ -64,8 +50,13 @@ public class GatewayResource {
             }
         }
 
-        ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
-        return resource.getStatus(false);
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
+            return resource.getStatus(repository);
+
+        } catch (DataException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+        }
     }
 
 
@@ -76,50 +67,83 @@ public class GatewayResource {
 
 
     @GET
-    @Path("{name}/{path:.*}")
+    @Path("{path:.*}")
     @SecurityRequirement(name = "apiKey")
-    public HttpServletResponse getPathByName(@PathParam("name") String name,
-                                             @PathParam("path") String inPath) {
+    public HttpServletResponse getPath(@PathParam("path") String inPath) {
         // Block requests from localhost, to prevent websites/apps from running javascript that fetches unvetted data
         Security.disallowLoopbackRequests(request);
-        return this.get(name, ResourceIdType.NAME, Service.WEBSITE, inPath, null, "", true, true);
-    }
-
-    @GET
-    @Path("{name}")
-    @SecurityRequirement(name = "apiKey")
-    public HttpServletResponse getIndexByName(@PathParam("name") String name) {
-        // Block requests from localhost, to prevent websites/apps from running javascript that fetches unvetted data
-        Security.disallowLoopbackRequests(request);
-        return this.get(name, ResourceIdType.NAME, Service.WEBSITE, "/", null, "", true, true);
-    }
-
-
-    // Optional /site alternative for backwards support
-
-    @GET
-    @Path("/site/{name}/{path:.*}")
-    public HttpServletResponse getSitePathByName(@PathParam("name") String name,
-                                                 @PathParam("path") String inPath) {
-        // Block requests from localhost, to prevent websites/apps from running javascript that fetches unvetted data
-        Security.disallowLoopbackRequests(request);
-        return this.get(name, ResourceIdType.NAME, Service.WEBSITE, inPath, null, "/site", true, true);
-    }
-
-    @GET
-    @Path("/site/{name}")
-    public HttpServletResponse getSiteIndexByName(@PathParam("name") String name) {
-        // Block requests from localhost, to prevent websites/apps from running javascript that fetches unvetted data
-        Security.disallowLoopbackRequests(request);
-        return this.get(name, ResourceIdType.NAME, Service.WEBSITE, "/", null, "/site", true, true);
+        return this.parsePath(inPath, "gateway", null, true, true);
     }
 
     
-    private HttpServletResponse get(String resourceId, ResourceIdType resourceIdType, Service service, String inPath,
-                                    String secret58, String prefix, boolean usePrefix, boolean async) {
+    private HttpServletResponse parsePath(String inPath, String qdnContext, String secret58, boolean includeResourceIdInPrefix, boolean async) {
 
-        ArbitraryDataRenderer renderer = new ArbitraryDataRenderer(resourceId, resourceIdType, service, inPath,
-                secret58, prefix, usePrefix, async, request, response, context);
+        if (inPath == null || inPath.equals("")) {
+            // Assume not a real file
+            return ArbitraryDataRenderer.getResponse(response, 404, "Error 404: File Not Found");
+        }
+
+        // Default service is WEBSITE
+        Service service = Service.WEBSITE;
+        String name = null;
+        String identifier = null;
+        String outPath = "";
+        List<String> prefixParts = new ArrayList<>();
+
+        if (!inPath.contains("/")) {
+            // Assume entire inPath is a registered name
+            name = inPath;
+        }
+        else {
+            // Parse the path to determine what we need to load
+            List<String> parts = new LinkedList<>(Arrays.asList(inPath.split("/")));
+
+            // Check if the first element is a service
+            try {
+                Service parsedService = Service.valueOf(parts.get(0).toUpperCase());
+                if (parsedService != null) {
+                    // First element matches a service, so we can assume it is one
+                    service = parsedService;
+                    parts.remove(0);
+                    prefixParts.add(service.name());
+                }
+            } catch (IllegalArgumentException e) {
+                // Not a service
+            }
+
+            if (parts.isEmpty()) {
+                // We need more than just a service
+                return ArbitraryDataRenderer.getResponse(response, 404, "Error 404: File Not Found");
+            }
+
+            // Service is removed, so assume first element is now a registered name
+            name = parts.get(0);
+            parts.remove(0);
+
+            if (!parts.isEmpty()) {
+                // Name is removed, so check if the first element is now an identifier
+                ArbitraryResourceStatus status = this.getStatus(service, name, parts.get(0), false);
+                if (status.getTotalChunkCount() > 0) {
+                    // Matched service, name and identifier combination - so assume this is an identifier and can be removed
+                    identifier = parts.get(0);
+                    parts.remove(0);
+                    prefixParts.add(identifier);
+                }
+            }
+
+            if (!parts.isEmpty()) {
+                // outPath can be built by combining any remaining parts
+                outPath = String.join("/", parts);
+            }
+        }
+
+        String prefix = StringUtils.join(prefixParts, "/");
+        if (prefix != null && prefix.length() > 0) {
+            prefix = "/" + prefix;
+        }
+
+        ArbitraryDataRenderer renderer = new ArbitraryDataRenderer(name, ResourceIdType.NAME, service, identifier, outPath,
+                secret58, prefix, includeResourceIdInPrefix, async, qdnContext, request, response, context);
         return renderer.render();
     }
 

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

@@ -0,0 +1,56 @@
+package org.qortal.api.model;
+
+import org.qortal.block.SelfSponsorshipAlgoV1Block;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.naming.NameData;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlElement;
+import java.util.ArrayList;
+import java.util.List;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class AccountPenaltyStats {
+
+	public Integer totalPenalties;
+	public Integer maxPenalty;
+	public Integer minPenalty;
+	public String penaltyHash;
+
+	protected AccountPenaltyStats() {
+	}
+
+	public AccountPenaltyStats(Integer totalPenalties, Integer maxPenalty, Integer minPenalty, String penaltyHash) {
+		this.totalPenalties = totalPenalties;
+		this.maxPenalty = maxPenalty;
+		this.minPenalty = minPenalty;
+		this.penaltyHash = penaltyHash;
+	}
+
+	public static AccountPenaltyStats fromAccounts(List<AccountData> accounts) {
+		int totalPenalties = 0;
+		Integer maxPenalty = null;
+		Integer minPenalty = null;
+
+		List<String> addresses = new ArrayList<>();
+		for (AccountData accountData : accounts) {
+			int penalty = accountData.getBlocksMintedPenalty();
+			addresses.add(accountData.getAddress());
+			totalPenalties++;
+
+			// Penalties are expressed as a negative number, so the min and the max are reversed here
+			if (maxPenalty == null || penalty < maxPenalty) maxPenalty = penalty;
+			if (minPenalty == null || penalty > minPenalty) minPenalty = penalty;
+		}
+
+		String penaltyHash = SelfSponsorshipAlgoV1Block.getHash(addresses);
+		return new AccountPenaltyStats(totalPenalties, maxPenalty, minPenalty, penaltyHash);
+	}
+
+
+	@Override
+	public String toString() {
+		return String.format("totalPenalties: %d, maxPenalty: %d, minPenalty: %d, penaltyHash: %s", totalPenalties, maxPenalty, minPenalty, penaltyHash == null ? "null" : penaltyHash);
+	}
+}

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

@@ -1,7 +1,8 @@
 package org.qortal.api.model;
 
 import io.swagger.v3.oas.annotations.media.Schema;
-import org.qortal.data.network.PeerChainTipData;
+import org.qortal.controller.Controller;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.network.PeerData;
 import org.qortal.network.Handshake;
 import org.qortal.network.Peer;
@@ -36,6 +37,7 @@ public class ConnectedPeer {
     public Long lastBlockTimestamp;
     public UUID connectionId;
     public String age;
+    public Boolean isTooDivergent;
 
     protected ConnectedPeer() {
     }
@@ -63,11 +65,16 @@ 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();
+        }
+
+        // Only include isTooDivergent decision if we've had the opportunity to request block summaries this peer
+        if (peer.getLastTooDivergentTime() != null) {
+            this.isTooDivergent = Controller.wasRecentlyTooDivergent.test(peer);
         }
     }
 

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

@@ -0,0 +1,16 @@
+package org.qortal.api.model;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class FileProperties {
+
+	public String filename;
+	public String mimeType;
+	public Long size;
+
+	public FileProperties() {
+	}
+
+}

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/PollVotes.java

@@ -0,0 +1,56 @@
+package org.qortal.api.model;
+
+import java.util.List;
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlElement;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+import org.qortal.data.voting.VoteOnPollData;
+
+@Schema(description = "Poll vote info, including voters")
+// All properties to be converted to JSON via JAX-RS
+@XmlAccessorType(XmlAccessType.FIELD)
+public class PollVotes {
+
+    @Schema(description = "List of individual votes")
+    @XmlElement(name = "votes")
+    public List<VoteOnPollData> votes;
+
+    @Schema(description = "Total number of votes")
+    public Integer totalVotes;
+
+    @Schema(description = "List of vote counts for each option")
+    public List<OptionCount> voteCounts;
+
+    // For JAX-RS
+    protected PollVotes() {
+    }
+
+    public PollVotes(List<VoteOnPollData> votes, Integer totalVotes, List<OptionCount> voteCounts) {
+        this.votes = votes;
+        this.totalVotes = totalVotes;
+        this.voteCounts = voteCounts;
+    }
+
+    @Schema(description = "Vote info")
+    // All properties to be converted to JSON via JAX-RS
+    @XmlAccessorType(XmlAccessType.FIELD)
+    public static class OptionCount {
+        @Schema(description = "Option name")
+        public String optionName;
+
+        @Schema(description = "Vote count")
+        public Integer voteCount;
+
+        // For JAX-RS
+        protected OptionCount() {
+        }
+
+        public OptionCount(String optionName, Integer voteCount) {
+            this.optionName = optionName;
+            this.voteCount = voteCount;
+        }
+    }
+}

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/proxy/resource/DevProxyServerResource.java

@@ -0,0 +1,164 @@
+package org.qortal.api.proxy.resource;
+
+import org.qortal.api.ApiError;
+import org.qortal.api.ApiExceptionFactory;
+import org.qortal.api.HTMLParser;
+import org.qortal.arbitrary.misc.Service;
+import org.qortal.controller.DevProxyManager;
+
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.PathParam;
+import javax.ws.rs.core.Context;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.ConnectException;
+import java.net.HttpURLConnection;
+import java.net.ProtocolException;
+import java.net.URL;
+import java.util.Enumeration;
+
+
+@Path("/")
+public class DevProxyServerResource {
+
+    @Context HttpServletRequest request;
+    @Context HttpServletResponse response;
+    @Context ServletContext context;
+
+
+    @GET
+    public HttpServletResponse getProxyIndex() {
+        return this.proxy("/");
+    }
+
+    @GET
+    @Path("{path:.*}")
+    public HttpServletResponse getProxyPath(@PathParam("path") String inPath) {
+        return this.proxy(inPath);
+    }
+
+    private HttpServletResponse proxy(String inPath) {
+        try {
+            String source = DevProxyManager.getInstance().getSourceHostAndPort();
+
+            if (!inPath.startsWith("/")) {
+                inPath = "/" + inPath;
+            }
+
+            String queryString = request.getQueryString() != null ? "?" + request.getQueryString() : "";
+
+            // Open URL
+            URL url = new URL(String.format("http://%s%s%s", source, inPath, queryString));
+            HttpURLConnection con = (HttpURLConnection) url.openConnection();
+
+            // Proxy the request data
+            this.proxyRequestToConnection(request, con);
+
+            try {
+                // Make the request and proxy the response code
+                response.setStatus(con.getResponseCode());
+            }
+            catch (ConnectException e) {
+
+                // Tey converting localhost / 127.0.0.1 to IPv6 [::1]
+                if (source.startsWith("localhost") || source.startsWith("127.0.0.1")) {
+                    int port = 80;
+                    String[] parts = source.split(":");
+                    if (parts.length > 1) {
+                        port = Integer.parseInt(parts[1]);
+                    }
+                    source = String.format("[::1]:%d", port);
+                }
+
+                // Retry connection
+                url = new URL(String.format("http://%s%s%s", source, inPath, queryString));
+                con = (HttpURLConnection) url.openConnection();
+                this.proxyRequestToConnection(request, con);
+                response.setStatus(con.getResponseCode());
+            }
+
+            // Proxy the response data back to the caller
+            this.proxyConnectionToResponse(con, response, inPath);
+
+        } catch (IOException e) {
+            throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, e.getMessage());
+        }
+
+        return response;
+    }
+
+    private void proxyRequestToConnection(HttpServletRequest request, HttpURLConnection con) throws ProtocolException {
+        // Proxy the request method
+        con.setRequestMethod(request.getMethod());
+
+        // Proxy the request headers
+        Enumeration<String> headerNames = request.getHeaderNames();
+        while (headerNames.hasMoreElements()) {
+            String headerName = headerNames.nextElement();
+            String headerValue = request.getHeader(headerName);
+            con.setRequestProperty(headerName, headerValue);
+        }
+
+        // TODO: proxy any POST parameters from "request" to "con"
+    }
+
+    private void proxyConnectionToResponse(HttpURLConnection con, HttpServletResponse response, String inPath) throws IOException {
+        // Proxy the response headers
+        for (int i = 0; ; i++) {
+            String headerKey = con.getHeaderFieldKey(i);
+            String headerValue = con.getHeaderField(i);
+            if (headerKey != null && headerValue != null) {
+                response.addHeader(headerKey, headerValue);
+                continue;
+            }
+            break;
+        }
+
+        // Read the response body
+        InputStream inputStream = con.getInputStream();
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        byte[] buffer = new byte[4096];
+        int bytesRead;
+        while ((bytesRead = inputStream.read(buffer)) != -1) {
+            outputStream.write(buffer, 0, bytesRead);
+        }
+        byte[] data = outputStream.toByteArray(); // TODO: limit file size that can be read into memory
+
+        // Close the streams
+        outputStream.close();
+        inputStream.close();
+
+        // Extract filename
+        String filename = "";
+        if (inPath.contains("/")) {
+            String[] parts = inPath.split("/");
+            if (parts.length > 0) {
+                filename = parts[parts.length - 1];
+            }
+        }
+
+        // Parse and modify output if needed
+        if (HTMLParser.isHtmlFile(filename)) {
+            // HTML file - needs to be parsed
+            HTMLParser htmlParser = new HTMLParser("", inPath, "", false, data, "proxy", Service.APP, null, "light", true);
+            htmlParser.addAdditionalHeaderTags();
+            response.addHeader("Content-Security-Policy", "default-src 'self' 'unsafe-inline' 'unsafe-eval'; media-src 'self' data: blob:; img-src 'self' data: blob:; connect-src 'self' ws:; font-src 'self' data:;");
+            response.setContentType(con.getContentType());
+            response.setContentLength(htmlParser.getData().length);
+            response.getOutputStream().write(htmlParser.getData());
+        }
+        else {
+            // Regular file - can be streamed directly
+            response.addHeader("Content-Security-Policy", "default-src 'self'");
+            response.setContentType(con.getContentType());
+            response.setContentLength(data.length);
+            response.getOutputStream().write(data);
+        }
+    }
+
+}

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

@@ -14,6 +14,7 @@ import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.*;
@@ -27,6 +28,7 @@ import org.qortal.api.ApiErrors;
 import org.qortal.api.ApiException;
 import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.Security;
+import org.qortal.api.model.AccountPenaltyStats;
 import org.qortal.api.model.ApiOnlineAccount;
 import org.qortal.api.model.RewardShareKeyRequest;
 import org.qortal.asset.Asset;
@@ -34,6 +36,7 @@ import org.qortal.controller.LiteNode;
 import org.qortal.controller.OnlineAccountsManager;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.account.AccountData;
+import org.qortal.data.account.AccountPenaltyData;
 import org.qortal.data.account.RewardShareData;
 import org.qortal.data.network.OnlineAccountData;
 import org.qortal.data.network.OnlineAccountLevel;
@@ -205,6 +208,10 @@ 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());
@@ -467,6 +474,54 @@ public class AddressesResource {
 		}
 	}
 
+	@GET
+	@Path("/penalties")
+	@Operation(
+			summary = "Get addresses with penalties",
+			description = "Returns a list of accounts with a blocksMintedPenalty",
+			responses = {
+					@ApiResponse(
+							description = "accounts with penalties",
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, array = @ArraySchema(schema = @Schema(implementation = AccountPenaltyData.class)))
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public List<AccountPenaltyData> getAccountsWithPenalties() {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<AccountData> accounts = repository.getAccountRepository().getPenaltyAccounts();
+			List<AccountPenaltyData> penalties = accounts.stream().map(a -> new AccountPenaltyData(a.getAddress(), a.getBlocksMintedPenalty())).collect(Collectors.toList());
+
+			return penalties;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+	@GET
+	@Path("/penalties/stats")
+	@Operation(
+			summary = "Get stats about current penalties",
+			responses = {
+					@ApiResponse(
+							description = "aggregated stats about accounts with penalties",
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, array = @ArraySchema(schema = @Schema(implementation = AccountPenaltyStats.class)))
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public AccountPenaltyStats getPenaltyStats() {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<AccountData> accounts = repository.getAccountRepository().getPenaltyAccounts();
+			return AccountPenaltyStats.fromAccounts(accounts);
+
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@POST
 	@Path("/publicize")
 	@Operation(

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

@@ -0,0 +1,83 @@
+package org.qortal.api.resource;
+
+import com.google.common.io.Resources;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.media.Content;
+import io.swagger.v3.oas.annotations.media.Schema;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+import io.swagger.v3.oas.annotations.Hidden;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import org.qortal.api.*;
+
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import javax.ws.rs.*;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+import java.io.IOException;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+
+
+@Path("/apps")
+@Tag(name = "Apps")
+public class AppsResource {
+
+    @Context HttpServletRequest request;
+    @Context HttpServletResponse response;
+    @Context ServletContext context;
+
+    @GET
+    @Path("/q-apps.js")
+    @Hidden // For internal Q-App API use only
+    @Operation(
+            summary = "Javascript interface for Q-Apps",
+            responses = {
+                    @ApiResponse(
+                            description = "javascript",
+                            content = @Content(
+                                    mediaType = MediaType.TEXT_PLAIN,
+                                    schema = @Schema(
+                                            type = "string"
+                                    )
+                            )
+                    )
+            }
+    )
+    public String getQAppsJs() {
+        URL url = Resources.getResource("q-apps/q-apps.js");
+        try {
+            return Resources.toString(url, StandardCharsets.UTF_8);
+        } catch (IOException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FILE_NOT_FOUND);
+        }
+    }
+
+    @GET
+    @Path("/q-apps-gateway.js")
+    @Hidden // For internal Q-App API use only
+    @Operation(
+            summary = "Gateway-specific interface for Q-Apps",
+            responses = {
+                    @ApiResponse(
+                            description = "javascript",
+                            content = @Content(
+                                    mediaType = MediaType.TEXT_PLAIN,
+                                    schema = @Schema(
+                                            type = "string"
+                                    )
+                            )
+                    )
+            }
+    )
+    public String getQAppsGatewayJs() {
+        URL url = Resources.getResource("q-apps/q-apps-gateway.js");
+        try {
+            return Resources.toString(url, StandardCharsets.UTF_8);
+        } catch (IOException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FILE_NOT_FOUND);
+        }
+    }
+
+}

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

@@ -1,6 +1,8 @@
 package org.qortal.api.resource;
 
 import com.google.common.primitives.Bytes;
+import com.j256.simplemagic.ContentInfo;
+import com.j256.simplemagic.ContentInfoUtil;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
 import io.swagger.v3.oas.annotations.media.ArraySchema;
@@ -12,11 +14,14 @@ 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.net.FileNameMap;
+import java.net.URLConnection;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
+import java.util.Objects;
 
 import javax.servlet.ServletContext;
 import javax.servlet.http.HttpServletRequest;
@@ -25,11 +30,13 @@ import javax.ws.rs.*;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 
+import org.apache.commons.io.FileUtils;
 import org.apache.commons.lang3.ArrayUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.bouncycastle.util.encoders.Base64;
 import org.qortal.api.*;
+import org.qortal.api.model.FileProperties;
 import org.qortal.api.resource.TransactionsResource.ConfirmationStatus;
 import org.qortal.arbitrary.*;
 import org.qortal.arbitrary.ArbitraryDataFile.ResourceIdType;
@@ -38,6 +45,8 @@ import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Category;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.Controller;
+import org.qortal.controller.arbitrary.ArbitraryDataCacheManager;
+import org.qortal.controller.arbitrary.ArbitraryDataRenderManager;
 import org.qortal.controller.arbitrary.ArbitraryDataStorageManager;
 import org.qortal.controller.arbitrary.ArbitraryMetadataManager;
 import org.qortal.data.account.AccountData;
@@ -45,6 +54,7 @@ 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;
@@ -56,8 +66,7 @@ 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.Base58;
-import org.qortal.utils.ZipUtils;
+import org.qortal.utils.*;
 
 @Path("/arbitrary")
 @Tag(name = "Arbitrary")
@@ -78,18 +87,22 @@ public class ArbitraryResource {
 					"- If default is set to true, only resources without identifiers will be returned.",
 			responses = {
 					@ApiResponse(
-							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceInfo.class))
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceData.class))
 					)
 			}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<ArbitraryResourceInfo> getResources(
+	public List<ArbitraryResourceData> getResources(
 			@QueryParam("service") Service service,
+			@QueryParam("name") String name,
 			@QueryParam("identifier") String identifier,
 			@Parameter(description = "Default resources (without identifiers) only") @QueryParam("default") Boolean defaultResource,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
+			@Parameter(description = "Include followed names only") @QueryParam("followedonly") Boolean followedOnly,
+			@Parameter(description = "Exclude blocked content") @QueryParam("excludeblocked") Boolean excludeBlocked,
+			@Parameter(description = "Filter names by list") @QueryParam("namefilter") String nameListFilter,
 			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
 			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata) {
 
@@ -106,20 +119,29 @@ public class ArbitraryResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "identifier cannot be specified when requesting a default resource");
 			}
 
-			List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-					.getArbitraryResources(service, identifier, null, defaultRes, limit, offset, reverse);
+			// Set up name filters if supplied
+			List<String> names = null;
+			if (name != null) {
+				// Filter using single name
+				names = Arrays.asList(name);
+			}
+			else if (nameListFilter != null) {
+				// Filter using supplied list of names
+				names = ResourceListManager.getInstance().getStringsInList(nameListFilter);
+				if (names.isEmpty()) {
+					// If list is empty (or doesn't exist) we can shortcut with empty response
+					return new ArrayList<>();
+				}
+			}
+
+			List<ArbitraryResourceData> resources = repository.getArbitraryRepository()
+					.getArbitraryResources(service, identifier, names, defaultRes, followedOnly, excludeBlocked,
+							includeMetadata, includeStatus, limit, offset, reverse);
 
 			if (resources == null) {
 				return new ArrayList<>();
 			}
 
-			if (includeStatus != null && includeStatus) {
-				resources = this.addStatusToResources(resources);
-			}
-			if (includeMetadata != null && includeMetadata) {
-				resources = this.addMetadataToResources(resources);
-			}
-
 			return resources;
 
 		} catch (DataException e) {
@@ -134,39 +156,66 @@ public class ArbitraryResource {
 					"If default is set to true, only resources without identifiers will be returned.",
 			responses = {
 					@ApiResponse(
-							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceInfo.class))
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceData.class))
 					)
 			}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<ArbitraryResourceInfo> searchResources(
+	public List<ArbitraryResourceData> searchResources(
 			@QueryParam("service") Service service,
-			@QueryParam("query") String query,
+			@Parameter(description = "Query (searches name, identifier, title and description fields)") @QueryParam("query") String query,
+			@Parameter(description = "Identifier (searches identifier field only)") @QueryParam("identifier") String identifier,
+			@Parameter(description = "Name (searches name field only)") @QueryParam("name") List<String> names,
+			@Parameter(description = "Title (searches title metadata field only)") @QueryParam("title") String title,
+			@Parameter(description = "Description (searches description metadata field only)") @QueryParam("description") String description,
+			@Parameter(description = "Prefix only (if true, only the beginning of fields are matched)") @QueryParam("prefix") Boolean prefixOnly,
+			@Parameter(description = "Exact match names only (if true, partial name matches are excluded)") @QueryParam("exactmatchnames") Boolean exactMatchNamesOnly,
 			@Parameter(description = "Default resources (without identifiers) only") @QueryParam("default") Boolean defaultResource,
+			@Parameter(description = "Search mode") @QueryParam("mode") SearchMode mode,
+			@Parameter(description = "Min level") @QueryParam("minlevel") Integer minLevel,
+			@Parameter(description = "Filter names by list (exact matches only)") @QueryParam("namefilter") String nameListFilter,
+			@Parameter(description = "Include followed names only") @QueryParam("followedonly") Boolean followedOnly,
+			@Parameter(description = "Exclude blocked content") @QueryParam("excludeblocked") Boolean excludeBlocked,
+			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
+			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata,
+			@Parameter(description = "Creation date before timestamp") @QueryParam("before") Long before,
+			@Parameter(description = "Creation date after timestamp") @QueryParam("after") Long after,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
-			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
-			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
-			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata) {
+			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 
 			boolean defaultRes = Boolean.TRUE.equals(defaultResource);
+			boolean usePrefixOnly = Boolean.TRUE.equals(prefixOnly);
 
-			List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-					.searchArbitraryResources(service, query, defaultRes, limit, offset, reverse);
+			List<String> exactMatchNames = new ArrayList<>();
+
+			if (nameListFilter != null) {
+				// Load names from supplied list of names
+				exactMatchNames.addAll(ResourceListManager.getInstance().getStringsInList(nameListFilter));
+
+				// If list is empty (or doesn't exist) we can shortcut with empty response
+				if (exactMatchNames.isEmpty()) {
+					return new ArrayList<>();
+				}
+			}
+
+			// Move names to exact match list, if requested
+			if (exactMatchNamesOnly != null && exactMatchNamesOnly && names != null) {
+				exactMatchNames.addAll(names);
+				names = null;
+			}
+
+			List<ArbitraryResourceData> resources = repository.getArbitraryRepository()
+					.searchArbitraryResources(service, query, identifier, names, title, description, usePrefixOnly,
+							exactMatchNames, defaultRes, mode, minLevel, followedOnly, excludeBlocked, includeMetadata, includeStatus,
+							before, after, limit, offset, reverse);
 
 			if (resources == null) {
 				return new ArrayList<>();
 			}
 
-			if (includeStatus != null && includeStatus) {
-				resources = this.addStatusToResources(resources);
-			}
-			if (includeMetadata != null && includeMetadata) {
-				resources = this.addMetadataToResources(resources);
-			}
-
 			return resources;
 
 		} catch (DataException e) {
@@ -174,67 +223,6 @@ public class ArbitraryResource {
 		}
 	}
 
-	@GET
-	@Path("/resources/names")
-	@Operation(
-			summary = "List arbitrary resources available on chain, grouped by creator's name",
-			responses = {
-					@ApiResponse(
-							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceInfo.class))
-					)
-			}
-	)
-	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<ArbitraryResourceNameInfo> getResourcesGroupedByName(
-			@QueryParam("service") Service service,
-			@QueryParam("identifier") String identifier,
-			@Parameter(description = "Default resources (without identifiers) only") @QueryParam("default") Boolean defaultResource,
-			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
-			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
-			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
-			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
-			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata) {
-
-		try (final Repository repository = RepositoryManager.getRepository()) {
-
-			// Treat empty identifier as null
-			if (identifier != null && identifier.isEmpty()) {
-				identifier = null;
-			}
-
-			// Ensure that "default" and "identifier" parameters cannot coexist
-			boolean defaultRes = Boolean.TRUE.equals(defaultResource);
-			if (defaultRes == true && identifier != null) {
-				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "identifier cannot be specified when requesting a default resource");
-			}
-
-			List<ArbitraryResourceNameInfo> creatorNames = repository.getArbitraryRepository()
-					.getArbitraryResourceCreatorNames(service, identifier, defaultRes, limit, offset, reverse);
-
-			for (ArbitraryResourceNameInfo creatorName : creatorNames) {
-				String name = creatorName.name;
-				if (name != null) {
-					List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-							.getArbitraryResources(service, identifier, name, defaultRes, null, null, reverse);
-
-					if (includeStatus != null && includeStatus) {
-						resources = this.addStatusToResources(resources);
-					}
-					if (includeMetadata != null && includeMetadata) {
-						resources = this.addMetadataToResources(resources);
-					}
-
-					creatorName.resources = resources;
-				}
-			}
-
-			return creatorNames;
-
-		} catch (DataException e) {
-			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
-		}
-	}
-
 	@GET
 	@Path("/resource/status/{service}/{name}")
 	@Operation(
@@ -246,14 +234,35 @@ public class ArbitraryResource {
 					)
 			}
 	)
-	@SecurityRequirement(name = "apiKey")
-	public ArbitraryResourceStatus getDefaultResourceStatus(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
-															@PathParam("service") Service service,
+	public ArbitraryResourceStatus getDefaultResourceStatus(@PathParam("service") Service service,
 															@PathParam("name") String name,
 															@QueryParam("build") Boolean build) {
 
-		Security.requirePriorAuthorizationOrApiKey(request, name, service, null);
-		return this.getStatus(service, name, null, build);
+		if (!Settings.getInstance().isQDNAuthBypassEnabled())
+			Security.requirePriorAuthorizationOrApiKey(request, name, service, null, null);
+
+		return ArbitraryTransactionUtils.getStatus(service, name, null, build, true);
+	}
+
+	@GET
+	@Path("/resource/properties/{service}/{name}/{identifier}")
+	@Operation(
+			summary = "Get properties of a QDN resource",
+			description = "This attempts a download of the data if it's not available locally. A filename will only be returned for single file resources. mimeType is only returned when it can be determined.",
+			responses = {
+					@ApiResponse(
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = FileProperties.class))
+					)
+			}
+	)
+	public FileProperties getResourceProperties(@PathParam("service") Service service,
+											    @PathParam("name") String name,
+											    @PathParam("identifier") String identifier) {
+
+		if (!Settings.getInstance().isQDNAuthBypassEnabled())
+			Security.requirePriorAuthorizationOrApiKey(request, name, service, identifier, null);
+
+		return this.getFileProperties(service, name, identifier);
 	}
 
 	@GET
@@ -267,15 +276,15 @@ public class ArbitraryResource {
 					)
 			}
 	)
-	@SecurityRequirement(name = "apiKey")
-	public ArbitraryResourceStatus getResourceStatus(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
-													 @PathParam("service") Service service,
+	public ArbitraryResourceStatus getResourceStatus(@PathParam("service") Service service,
 													 @PathParam("name") String name,
 													 @PathParam("identifier") String identifier,
 													 @QueryParam("build") Boolean build) {
 
-		Security.requirePriorAuthorizationOrApiKey(request, name, service, identifier);
-		return this.getStatus(service, name, identifier, build);
+		if (!Settings.getInstance().isQDNAuthBypassEnabled())
+			Security.requirePriorAuthorizationOrApiKey(request, name, service, identifier, null);
+
+		return ArbitraryTransactionUtils.getStatus(service, name, identifier, build, true);
 	}
 
 
@@ -460,21 +469,19 @@ public class ArbitraryResource {
 			summary = "List arbitrary resources hosted by this node",
 			responses = {
 					@ApiResponse(
-							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceInfo.class))
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = ArbitraryResourceData.class))
 					)
 			}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<ArbitraryResourceInfo> getHostedResources(
+	public List<ArbitraryResourceData> getHostedResources(
 			@HeaderParam(Security.API_KEY_HEADER) String apiKey,
-			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
-			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@QueryParam("query") String query) {
 		Security.checkApiCallAllowed(request);
 
-		List<ArbitraryResourceInfo> resources = new ArrayList<>();
+		List<ArbitraryResourceData> resources = new ArrayList<>();
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			
@@ -487,20 +494,16 @@ public class ArbitraryResource {
 			}
 
 			for (ArbitraryTransactionData transactionData : transactionDataList) {
-				ArbitraryResourceInfo arbitraryResourceInfo = new ArbitraryResourceInfo();
-				arbitraryResourceInfo.name = transactionData.getName();
-				arbitraryResourceInfo.service = transactionData.getService();
-				arbitraryResourceInfo.identifier = transactionData.getIdentifier();
-				if (!resources.contains(arbitraryResourceInfo)) {
-					resources.add(arbitraryResourceInfo);
+				if (transactionData.getService() == null) {
+					continue;
+				}
+				ArbitraryResourceData arbitraryResourceData = new ArbitraryResourceData();
+				arbitraryResourceData.name = transactionData.getName();
+				arbitraryResourceData.service = transactionData.getService();
+				arbitraryResourceData.identifier = transactionData.getIdentifier();
+				if (!resources.contains(arbitraryResourceData)) {
+					resources.add(arbitraryResourceData);
 				}
-			}
-
-			if (includeStatus != null && includeStatus) {
-				resources = this.addStatusToResources(resources);
-			}
-			if (includeMetadata != null && includeMetadata) {
-				resources = this.addMetadataToResources(resources);
 			}
 
 			return resources;
@@ -529,8 +532,14 @@ public class ArbitraryResource {
 								  @PathParam("identifier") String identifier) {
 
 		Security.checkApiCallAllowed(request);
-		ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
-		return resource.delete();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
+			return resource.delete(repository, false);
+
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
 	}
 
 	@POST
@@ -622,11 +631,10 @@ public class ArbitraryResource {
 					)
 			}
 	)
-	@SecurityRequirement(name = "apiKey")
-	public HttpServletResponse get(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
-								   @PathParam("service") Service service,
+	public HttpServletResponse get(@PathParam("service") Service service,
 								   @PathParam("name") String name,
 								   @QueryParam("filepath") String filepath,
+								   @QueryParam("encoding") String encoding,
 								   @QueryParam("rebuild") boolean rebuild,
 								   @QueryParam("async") boolean async,
 								   @QueryParam("attempts") Integer attempts) {
@@ -636,7 +644,7 @@ public class ArbitraryResource {
 			Security.checkApiCallAllowed(request);
 		}
 
-		return this.download(service, name, null, filepath, rebuild, async, attempts);
+		return this.download(service, name, null, filepath, encoding, rebuild, async, attempts);
 	}
 
 	@GET
@@ -656,22 +664,21 @@ public class ArbitraryResource {
 					)
 			}
 	)
-	@SecurityRequirement(name = "apiKey")
-	public HttpServletResponse get(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
-								   @PathParam("service") Service service,
+	public HttpServletResponse get(@PathParam("service") Service service,
 								   @PathParam("name") String name,
 								   @PathParam("identifier") String identifier,
 								   @QueryParam("filepath") String filepath,
+								   @QueryParam("encoding") String encoding,
 								   @QueryParam("rebuild") boolean rebuild,
 								   @QueryParam("async") boolean async,
 								   @QueryParam("attempts") Integer attempts) {
 
 		// Authentication can be bypassed in the settings, for those running public QDN nodes
 		if (!Settings.getInstance().isQDNAuthBypassEnabled()) {
-			Security.checkApiCallAllowed(request);
+			Security.checkApiCallAllowed(request, null);
 		}
 
-		return this.download(service, name, identifier, filepath, rebuild, async, attempts);
+		return this.download(service, name, identifier, filepath, encoding, rebuild, async, attempts);
 	}
 
 
@@ -693,19 +700,15 @@ public class ArbitraryResource {
 					)
 			}
 	)
-	@SecurityRequirement(name = "apiKey")
-	public ArbitraryResourceMetadata getMetadata(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
-							  @PathParam("service") Service service,
-							  @PathParam("name") String name,
-							  @PathParam("identifier") String identifier) {
-		Security.checkApiCallAllowed(request);
-
+	public ArbitraryResourceMetadata getMetadata(@PathParam("service") Service service,
+							  					 @PathParam("name") String name,
+							  					 @PathParam("identifier") String identifier) {
 		ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
 
 		try {
 			ArbitraryDataTransactionMetadata transactionMetadata = ArbitraryMetadataManager.getInstance().fetchMetadata(resource, false);
 			if (transactionMetadata != null) {
-				ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
+				ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata, true);
 				if (resourceMetadata != null) {
 					return resourceMetadata;
 				}
@@ -719,7 +722,7 @@ public class ArbitraryResource {
 			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FILE_NOT_FOUND, e.getMessage());
 		}
 
-		throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_DATA);
+		throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FILE_NOT_FOUND);
 	}
 
 
@@ -759,6 +762,8 @@ public class ArbitraryResource {
 					   @QueryParam("description") String description,
 					   @QueryParam("tags") List<String> tags,
 					   @QueryParam("category") Category category,
+					   @QueryParam("fee") Long fee,
+					   @QueryParam("preview") Boolean preview,
 					   String path) {
 		Security.checkApiCallAllowed(request);
 
@@ -767,7 +772,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, path, null, null, false,
-				title, description, tags, category);
+				fee, null, title, description, tags, category, preview);
 	}
 
 	@POST
@@ -804,6 +809,8 @@ public class ArbitraryResource {
 					   @QueryParam("description") String description,
 					   @QueryParam("tags") List<String> tags,
 					   @QueryParam("category") Category category,
+					   @QueryParam("fee") Long fee,
+					   @QueryParam("preview") Boolean preview,
 					   String path) {
 		Security.checkApiCallAllowed(request);
 
@@ -812,7 +819,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, path, null, null, false,
-				title, description, tags, category);
+				fee, null, title, description, tags, category, preview);
 	}
 
 
@@ -850,6 +857,9 @@ public class ArbitraryResource {
 										@QueryParam("description") String description,
 										@QueryParam("tags") List<String> tags,
 										@QueryParam("category") Category category,
+										@QueryParam("filename") String filename,
+										@QueryParam("fee") Long fee,
+										@QueryParam("preview") Boolean preview,
 										String base64) {
 		Security.checkApiCallAllowed(request);
 
@@ -858,7 +868,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, null, null, base64, false,
-				title, description, tags, category);
+				fee, filename, title, description, tags, category, preview);
 	}
 
 	@POST
@@ -893,6 +903,9 @@ public class ArbitraryResource {
 										@QueryParam("description") String description,
 										@QueryParam("tags") List<String> tags,
 										@QueryParam("category") Category category,
+										@QueryParam("filename") String filename,
+										@QueryParam("fee") Long fee,
+										@QueryParam("preview") Boolean preview,
 										String base64) {
 		Security.checkApiCallAllowed(request);
 
@@ -901,7 +914,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, null, null, base64, false,
-				title, description, tags, category);
+				fee, filename, title, description, tags, category, preview);
 	}
 
 
@@ -938,6 +951,8 @@ public class ArbitraryResource {
 								 @QueryParam("description") String description,
 								 @QueryParam("tags") List<String> tags,
 								 @QueryParam("category") Category category,
+								 @QueryParam("fee") Long fee,
+								 @QueryParam("preview") Boolean preview,
 								 String base64Zip) {
 		Security.checkApiCallAllowed(request);
 
@@ -946,7 +961,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, null, null, base64Zip, true,
-				title, description, tags, category);
+				fee, null, title, description, tags, category, preview);
 	}
 
 	@POST
@@ -981,6 +996,8 @@ public class ArbitraryResource {
 								 @QueryParam("description") String description,
 								 @QueryParam("tags") List<String> tags,
 								 @QueryParam("category") Category category,
+								 @QueryParam("fee") Long fee,
+								 @QueryParam("preview") Boolean preview,
 								 String base64Zip) {
 		Security.checkApiCallAllowed(request);
 
@@ -989,7 +1006,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, null, null, base64Zip, true,
-				title, description, tags, category);
+				fee, null, title, description, tags, category, preview);
 	}
 
 
@@ -1029,6 +1046,9 @@ public class ArbitraryResource {
 							 @QueryParam("description") String description,
 							 @QueryParam("tags") List<String> tags,
 							 @QueryParam("category") Category category,
+							 @QueryParam("filename") String filename,
+							 @QueryParam("fee") Long fee,
+							 @QueryParam("preview") Boolean preview,
 							 String string) {
 		Security.checkApiCallAllowed(request);
 
@@ -1037,7 +1057,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, null, string, null, false,
-				title, description, tags, category);
+				fee, filename, title, description, tags, category, preview);
 	}
 
 	@POST
@@ -1074,6 +1094,9 @@ public class ArbitraryResource {
 							 @QueryParam("description") String description,
 							 @QueryParam("tags") List<String> tags,
 							 @QueryParam("category") Category category,
+							 @QueryParam("filename") String filename,
+							 @QueryParam("fee") Long fee,
+							 @QueryParam("preview") Boolean preview,
 							 String string) {
 		Security.checkApiCallAllowed(request);
 
@@ -1082,15 +1105,78 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, null, string, null, false,
-				title, description, tags, category);
+				fee, filename, title, description, tags, category, preview);
+	}
+
+
+	@POST
+	@Path("/resources/cache/rebuild")
+	@Operation(
+			summary = "Rebuild arbitrary resources cache from transactions",
+			responses = {
+					@ApiResponse(
+							description = "true on success",
+							content = @Content(
+									mediaType = MediaType.TEXT_PLAIN,
+									schema = @Schema(
+											type = "boolean"
+									)
+							)
+					)
+			}
+	)
+	@SecurityRequirement(name = "apiKey")
+	public String rebuildCache(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+		Security.checkApiCallAllowed(request);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			ArbitraryDataCacheManager.getInstance().buildArbitraryResourcesCache(repository, true);
+
+			return "true";
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
+		}
 	}
 
 
 	// Shared methods
 
+	private String preview(String directoryPath, Service service) {
+		Security.checkApiCallAllowed(request);
+		ArbitraryTransactionData.Method method = ArbitraryTransactionData.Method.PUT;
+		ArbitraryTransactionData.Compression compression = ArbitraryTransactionData.Compression.ZIP;
+
+		ArbitraryDataWriter arbitraryDataWriter = new ArbitraryDataWriter(Paths.get(directoryPath),
+				null, service, null, method, compression,
+				null, null, null, null);
+		try {
+			arbitraryDataWriter.save();
+		} catch (IOException | DataException | InterruptedException | MissingDataException e) {
+			LOGGER.info("Unable to create arbitrary data file: {}", e.getMessage());
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
+		} catch (RuntimeException e) {
+			LOGGER.info("Unable to create arbitrary data file: {}", e.getMessage());
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_DATA, e.getMessage());
+		}
+
+		ArbitraryDataFile arbitraryDataFile = arbitraryDataWriter.getArbitraryDataFile();
+		if (arbitraryDataFile != null) {
+			String digest58 = arbitraryDataFile.digest58();
+			if (digest58 != null) {
+				// Pre-authorize resource
+				ArbitraryDataResource resource = new ArbitraryDataResource(digest58, null, null, null);
+				ArbitraryDataRenderManager.getInstance().addToAuthorizedResources(resource);
+
+				return "/render/hash/" + digest58 + "?secret=" + Base58.encode(arbitraryDataFile.getSecret());
+			}
+		}
+		return "Unable to generate preview URL";
+	}
+
 	private String upload(Service service, String name, String identifier,
-						  String path, String string, String base64, boolean zipped,
-						  String title, String description, List<String> tags, Category category) {
+						  String path, String string, String base64, boolean zipped, Long fee, String filename,
+						  String title, String description, List<String> tags, Category category,
+						  Boolean preview) {
 		// Fetch public key from registered name
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			NameData nameData = repository.getNameRepository().fromName(name);
@@ -1099,7 +1185,12 @@ public class ArbitraryResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, error);
 			}
 
-			if (!Controller.getInstance().isUpToDate()) {
+			final Long now = NTP.getTime();
+			if (now == null) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.NO_TIME_SYNC);
+			}
+			final Long minLatestBlockTimestamp = now - (60 * 60 * 1000L);
+			if (!Controller.getInstance().isUpToDate(minLatestBlockTimestamp)) {
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCKCHAIN_NEEDS_SYNC);
 			}
 
@@ -1113,7 +1204,12 @@ public class ArbitraryResource {
 			if (path == null) {
 				// See if we have a string instead
 				if (string != null) {
-					File tempFile = File.createTempFile("qortal-", ".tmp");
+					if (filename == null) {
+						// Use current time as filename
+						filename = String.format("qortal-%d", NTP.getTime());
+					}
+					java.nio.file.Path tempDirectory = Files.createTempDirectory("qortal-");
+					File tempFile = Paths.get(tempDirectory.toString(), filename).toFile();
 					tempFile.deleteOnExit();
 					BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile.toPath().toString()));
 					writer.write(string);
@@ -1123,7 +1219,12 @@ public class ArbitraryResource {
 				}
 				// ... or base64 encoded raw data
 				else if (base64 != null) {
-					File tempFile = File.createTempFile("qortal-", ".tmp");
+					if (filename == null) {
+						// Use current time as filename
+						filename = String.format("qortal-%d", NTP.getTime());
+					}
+					java.nio.file.Path tempDirectory = Files.createTempDirectory("qortal-");
+					File tempFile = Paths.get(tempDirectory.toString(), filename).toFile();
 					tempFile.deleteOnExit();
 					Files.write(tempFile.toPath(), Base64.decode(base64));
 					path = tempFile.toPath().toString();
@@ -1146,15 +1247,25 @@ public class ArbitraryResource {
 					// The actual data will be in a randomly-named subfolder of tempDirectory
 					// Remove hidden folders, i.e. starting with "_", as some systems can add them, e.g. "__MACOSX"
 					String[] files = tempDirectory.toFile().list((parent, child) -> !child.startsWith("_"));
-					if (files.length == 1) { // Single directory or file only
+					if (files != null && files.length == 1) { // Single directory or file only
 						path = Paths.get(tempDirectory.toString(), files[0]).toString();
 					}
 				}
 			}
 
+			// Finish here if user has requested a preview
+			if (preview != null && preview == true) {
+				return this.preview(path, service);
+			}
+
+			// Default to zero fee if not specified
+			if (fee == null) {
+				fee = 0L;
+			}
+
 			try {
 				ArbitraryDataTransactionBuilder transactionBuilder = new ArbitraryDataTransactionBuilder(
-						repository, publicKey58, Paths.get(path), name, null, service, identifier,
+						repository, publicKey58, fee, Paths.get(path), name, null, service, identifier,
 						title, description, tags, category
 				);
 
@@ -1168,15 +1279,16 @@ public class ArbitraryResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_DATA, e.getMessage());
 			}
 
-		} catch (DataException | IOException e) {
+		} catch (Exception e) {
+			LOGGER.info("Exception when publishing data: ", e);
 			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
 		}
 	}
 
-	private HttpServletResponse download(Service service, String name, String identifier, String filepath, boolean rebuild, boolean async, Integer maxAttempts) {
+	private HttpServletResponse download(Service service, String name, String identifier, String filepath, String encoding, boolean rebuild, boolean async, Integer maxAttempts) {
 
-		ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(name, ArbitraryDataFile.ResourceIdType.NAME, service, identifier);
 		try {
+			ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(name, ArbitraryDataFile.ResourceIdType.NAME, service, identifier);
 
 			int attempts = 0;
 			if (maxAttempts == null) {
@@ -1216,7 +1328,7 @@ public class ArbitraryResource {
 			if (filepath == null || filepath.isEmpty()) {
 				// No file path supplied - so check if this is a single file resource
 				String[] files = ArrayUtils.removeElement(outputPath.toFile().list(), ".qortal");
-				if (files.length == 1) {
+				if (files != null && files.length == 1) {
 					// This is a single file resource
 					filepath = files[0];
 				}
@@ -1226,13 +1338,50 @@ public class ArbitraryResource {
 				}
 			}
 
-			// TODO: limit file size that can be read into memory
 			java.nio.file.Path path = Paths.get(outputPath.toString(), filepath);
 			if (!Files.exists(path)) {
 				String message = String.format("No file exists at filepath: %s", filepath);
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, message);
 			}
-			byte[] data = Files.readAllBytes(path);
+
+			byte[] data;
+			int fileSize = (int)path.toFile().length();
+			int length = fileSize;
+
+			// Parse "Range" header
+			Integer rangeStart = null;
+			Integer rangeEnd = null;
+			String range = request.getHeader("Range");
+			if (range != null) {
+				range = range.replace("bytes=", "");
+				String[] parts = range.split("-");
+				rangeStart = (parts != null && parts.length > 0) ? Integer.parseInt(parts[0]) : null;
+				rangeEnd = (parts != null && parts.length > 1) ? Integer.parseInt(parts[1]) : fileSize;
+			}
+
+			if (rangeStart != null && rangeEnd != null) {
+				// We have a range, so update the requested length
+				length = rangeEnd - rangeStart;
+			}
+
+			if (length < fileSize && encoding == null) {
+				// Partial content requested, and not encoding the data
+				response.setStatus(206);
+				response.addHeader("Content-Range", String.format("bytes %d-%d/%d", rangeStart, rangeEnd-1, fileSize));
+				data = FilesystemUtils.readFromFile(path.toString(), rangeStart, length);
+			}
+			else {
+				// Full content requested (or encoded data)
+				response.setStatus(200);
+				data = Files.readAllBytes(path); // TODO: limit file size that can be read into memory
+			}
+
+			// Encode the data if requested
+			if (encoding != null && Objects.equals(encoding.toLowerCase(), "base64")) {
+				data = Base64.encode(data);
+			}
+
+			response.addHeader("Accept-Ranges", "bytes");
 			response.setContentType(context.getMimeType(path.toString()));
 			response.setContentLength(data.length);
 			response.getOutputStream().write(data);
@@ -1244,59 +1393,44 @@ public class ArbitraryResource {
 		}
 	}
 
+	private FileProperties getFileProperties(Service service, String name, String identifier) {
+		try {
+			ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(name, ArbitraryDataFile.ResourceIdType.NAME, service, identifier);
+			arbitraryDataReader.loadSynchronously(false);
+			java.nio.file.Path outputPath = arbitraryDataReader.getFilePath();
+			if (outputPath == null) {
+				// Assume the resource doesn't exist
+				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FILE_NOT_FOUND, "File not found");
+			}
 
-	private ArbitraryResourceStatus getStatus(Service service, String name, String identifier, Boolean build) {
+			FileProperties fileProperties = new FileProperties();
+			fileProperties.size = FileUtils.sizeOfDirectory(outputPath.toFile());
 
-		// 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);
+			String[] files = ArrayUtils.removeElement(outputPath.toFile().list(), ".qortal");
+			if (files.length == 1) {
+				String filename = files[0];
+				java.nio.file.Path filePath = Paths.get(outputPath.toString(), files[0]);
+				ContentInfoUtil util = new ContentInfoUtil();
+				ContentInfo info = util.findMatch(filePath.toFile());
+				String mimeType;
+				if (info != null) {
+					// Attempt to extract MIME type from file contents
+					mimeType = info.getMimeType();
 				}
-			} 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<>();
-		for (ArbitraryResourceInfo resourceInfo : resources) {
-			try {
-				ArbitraryDataResource resource = new ArbitraryDataResource(resourceInfo.name, ResourceIdType.NAME,
-						resourceInfo.service, resourceInfo.identifier);
-				ArbitraryResourceStatus status = resource.getStatus(true);
-				if (status != null) {
-					resourceInfo.status = status;
+				else {
+					// Fall back to using the filename
+					FileNameMap fileNameMap = URLConnection.getFileNameMap();
+					mimeType = fileNameMap.getContentTypeFor(filename);
 				}
-				updatedResources.add(resourceInfo);
-
-			} catch (Exception e) {
-				// Catch and log all exceptions, since some systems are experiencing 500 errors when including statuses
-				LOGGER.info("Caught exception when adding status to resource %s: %s", resourceInfo, e.toString());
+				fileProperties.filename = filename;
+				fileProperties.mimeType = mimeType;
 			}
-		}
-		return updatedResources;
-	}
 
-	private List<ArbitraryResourceInfo> addMetadataToResources(List<ArbitraryResourceInfo> resources) {
-		// Add metadata fields to each resource if they exist
-		List<ArbitraryResourceInfo> updatedResources = new ArrayList<>();
-		for (ArbitraryResourceInfo resourceInfo : resources) {
-			ArbitraryDataResource resource = new ArbitraryDataResource(resourceInfo.name, ResourceIdType.NAME,
-					resourceInfo.service, resourceInfo.identifier);
-			ArbitraryDataTransactionMetadata transactionMetadata = resource.getLatestTransactionMetadata();
-			ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
-			if (resourceMetadata != null) {
-				resourceInfo.metadata = resourceMetadata;
-			}
-			updatedResources.add(resourceInfo);
+			return fileProperties;
+
+		} catch (Exception e) {
+			LOGGER.debug(String.format("Unable to load %s %s: %s", service, name, e.getMessage()));
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FILE_NOT_FOUND, e.getMessage());
 		}
-		return updatedResources;
 	}
 }

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

@@ -48,6 +48,7 @@ import org.qortal.repository.RepositoryManager;
 import org.qortal.transform.TransformationException;
 import org.qortal.transform.block.BlockTransformer;
 import org.qortal.utils.Base58;
+import org.qortal.utils.Triple;
 
 @Path("/blocks")
 @Tag(name = "Blocks")
@@ -114,7 +115,7 @@ 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 +126,7 @@ 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 +137,44 @@ 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);
+            Triple<byte[], Integer, Integer> serializedBlock = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, false, repository);
+            if (serializedBlock != null) {
+				byte[] bytes = serializedBlock.getA();
+				Integer serializationVersion = serializedBlock.getB();
+				if (version != serializationVersion) {
+					// TODO: we could quite easily reserialize the block with the requested version
+					throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Block is not stored using requested serialization version.");
+				}
+				return Base58.encode(bytes);
             }
 
             throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCK_UNKNOWN);
@@ -197,14 +222,25 @@ public class BlocksResource {
 		}
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-		    // Check if the block exists in either the database or archive
-			if (repository.getBlockRepository().getHeightFromSignature(signature) == 0 &&
-					repository.getBlockArchiveRepository().getHeightFromSignature(signature) == 0) {
-				// Not found in either the database or archive
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCK_UNKNOWN);
-            }
+			// Check if the block exists in either the database or archive
+			int height = repository.getBlockRepository().getHeightFromSignature(signature);
+			if (height == 0) {
+				height = repository.getBlockArchiveRepository().getHeightFromSignature(signature);
+				if (height == 0) {
+					// Not found in either the database or archive
+					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCK_UNKNOWN);
+				}
+			}
 
-			return repository.getBlockRepository().getTransactionsFromSignature(signature, limit, offset, reverse);
+			List<byte[]> signatures = repository.getTransactionRepository().getSignaturesMatchingCriteria(null, null, height, height);
+
+			// Expand signatures to transactions
+			List<TransactionData> transactions = new ArrayList<>(signatures.size());
+			for (byte[] s : signatures) {
+				transactions.add(repository.getTransactionRepository().fromSignature(s));
+			}
+
+			return transactions;
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
@@ -613,13 +649,16 @@ public class BlocksResource {
 	@ApiErrors({
 		ApiError.REPOSITORY_ISSUE
 	})
-	public List<BlockData> getBlockRange(@PathParam("height") int height, @Parameter(
-		ref = "count"
-	) @QueryParam("count") int count) {
+	public List<BlockData> getBlockRange(@PathParam("height") int height,
+										 @Parameter(ref = "count") @QueryParam("count") int count,
+										 @Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
+										 @QueryParam("includeOnlineSignatures") Boolean includeOnlineSignatures) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			List<BlockData> blocks = new ArrayList<>();
+			boolean shouldReverse = (reverse != null && reverse == true);
 
-			for (/* count already set */; count > 0; --count, ++height) {
+			int i = 0;
+			while (i < count) {
 				BlockData blockData = repository.getBlockRepository().fromHeight(height);
 				if (blockData == null) {
 					// Not found - try the archive
@@ -629,8 +668,14 @@ public class BlocksResource {
 						break;
 					}
 				}
+				if (includeOnlineSignatures == null || includeOnlineSignatures == false) {
+					blockData.setOnlineAccountsSignatures(null);
+				}
 
 				blocks.add(blockData);
+
+				height = shouldReverse ? height - 1 : height + 1;
+				i++;
 			}
 
 			return blocks;

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

@@ -40,6 +40,8 @@ import org.qortal.utils.Base58;
 
 import com.google.common.primitives.Bytes;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @Path("/chat")
 @Tag(name = "Chat")
 public class ChatResource {
@@ -69,6 +71,11 @@ 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,
+			@QueryParam("chatreference") String chatReference,
+			@QueryParam("haschatreference") Boolean hasChatReference,
+			@QueryParam("sender") String sender,
+			@QueryParam("encoding") Encoding encoding,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
@@ -87,18 +94,132 @@ 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);
+
+		byte[] chatReferenceBytes = null;
+		if (chatReference != null)
+			chatReferenceBytes = Base58.decode(chatReference);
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			return repository.getChatRepository().getMessagesMatchingCriteria(
 					before,
 					after,
 					txGroupId,
+					referenceBytes,
+					chatReferenceBytes,
+					hasChatReference,
 					involvingAddresses,
+					sender,
+					encoding,
 					limit, offset, reverse);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
 	}
 
+	@GET
+	@Path("/messages/count")
+	@Operation(
+			summary = "Count chat messages",
+			description = "Returns count of CHAT messages that match criteria. Must provide EITHER 'txGroupId' OR two 'involving' addresses.",
+			responses = {
+					@ApiResponse(
+							description = "count of messages",
+							content = @Content(
+									mediaType = MediaType.TEXT_PLAIN,
+									schema = @Schema(
+											type = "integer"
+									)
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public int countChatMessages(@QueryParam("before") Long before, @QueryParam("after") Long after,
+										@QueryParam("txGroupId") Integer txGroupId,
+										@QueryParam("involving") List<String> involvingAddresses,
+										@QueryParam("reference") String reference,
+										@QueryParam("chatreference") String chatReference,
+										@QueryParam("haschatreference") Boolean hasChatReference,
+										@QueryParam("sender") String sender,
+										@QueryParam("encoding") Encoding encoding,
+										@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
+										@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
+										@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
+		// Check args meet expectations
+		if ((txGroupId == null && involvingAddresses.size() != 2)
+				|| (txGroupId != null && !involvingAddresses.isEmpty()))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		// Check any provided addresses are valid
+		if (involvingAddresses.stream().anyMatch(address -> !Crypto.isValidAddress(address)))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
+
+		if (before != null && before < 1500000000000L)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		if (after != null && after < 1500000000000L)
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+		byte[] referenceBytes = null;
+		if (reference != null)
+			referenceBytes = Base58.decode(reference);
+
+		byte[] chatReferenceBytes = null;
+		if (chatReference != null)
+			chatReferenceBytes = Base58.decode(chatReference);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			return repository.getChatRepository().getMessagesMatchingCriteria(
+					before,
+					after,
+					txGroupId,
+					referenceBytes,
+					chatReferenceBytes,
+					hasChatReference,
+					involvingAddresses,
+					sender,
+					encoding,
+					limit, offset, reverse).size();
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+	@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, @QueryParam("encoding") Encoding encoding) {
+		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, encoding);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@GET
 	@Path("/active/{address}")
 	@Operation(
@@ -116,12 +237,12 @@ public class ChatResource {
 		}
 	)
 	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
-	public ActiveChats getActiveChats(@PathParam("address") String address) {
+	public ActiveChats getActiveChats(@PathParam("address") String address, @QueryParam("encoding") Encoding encoding) {
 		if (address == null || !Crypto.isValidAddress(address))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			return repository.getChatRepository().getActiveChats(address);
+			return repository.getChatRepository().getActiveChats(address, encoding);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}

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

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainBitcoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Bitcoin block height",
+		description = "Returns the height of the most recent block in the Bitcoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getBitcoinHeight() {
+		Bitcoin bitcoin = Bitcoin.getInstance();
+
+		try {
+			Integer height = bitcoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainBitcoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = bitcoin.getWalletBalanceFromTransactions(key58);
+			Long balance = bitcoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainBitcoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address 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 String getUnusedBitcoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Bitcoin bitcoin = Bitcoin.getInstance();
+
+		if (!bitcoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return bitcoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

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

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainDigibyteResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Digibyte block height",
+		description = "Returns the height of the most recent block in the Digibyte chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getDigibyteHeight() {
+		Digibyte digibyte = Digibyte.getInstance();
+
+		try {
+			Integer height = digibyte.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainDigibyteResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = digibyte.getWalletBalanceFromTransactions(key58);
+			Long balance = digibyte.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainDigibyteResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address 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 String getUnusedDigibyteReceiveAddress(@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.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

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

@@ -21,6 +21,7 @@ import org.qortal.crosschain.SimpleTransaction;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -33,6 +34,37 @@ public class CrossChainDogecoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Dogecoin block height",
+		description = "Returns the height of the most recent block in the Dogecoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getDogecoinHeight() {
+		Dogecoin dogecoin = Dogecoin.getInstance();
+
+		try {
+			Integer height = dogecoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -66,7 +98,7 @@ public class CrossChainDogecoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = dogecoin.getWalletBalanceFromTransactions(key58);
+			Long balance = dogecoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -116,6 +148,45 @@ public class CrossChainDogecoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address 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 String getUnusedDogecoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Dogecoin dogecoin = Dogecoin.getInstance();
+
+		if (!dogecoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return dogecoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

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;
@@ -9,6 +10,8 @@ import io.swagger.v3.oas.annotations.tags.Tag;
 
 import java.math.BigDecimal;
 import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.*;
@@ -284,6 +287,12 @@ 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 +372,6 @@ 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);
@@ -574,70 +579,108 @@ 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);
 			}
 
 			List<TradeBotData> allTradeBotData = repository.getCrossChainRepository().getAllTradeBotData();
-			TradeBotData tradeBotData = allTradeBotData.stream().filter(tradeBotDataItem -> tradeBotDataItem.getAtAddress().equals(atAddress)).findFirst().orElse(null);
-			if (tradeBotData == null)
+			List<TradeBotData> tradeBotDataList = allTradeBotData.stream().filter(tradeBotDataItem -> tradeBotDataItem.getAtAddress().equals(atAddress)).collect(Collectors.toList());
+			if (tradeBotDataList == null || tradeBotDataList.isEmpty())
 				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);
-			}
+			// Loop through all matching entries for this AT address, as there might be more than one
+			for (TradeBotData tradeBotData : tradeBotDataList) {
 
-			int lockTime = tradeBotData.getLockTimeA();
+				if (tradeBotData == null)
+					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
-			// We can't refund P2SH-A until lockTime-A has passed
-			if (NTP.getTime() <= lockTime * 1000L)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
+				int lockTime = tradeBotData.getLockTimeA();
 
-			// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-			int medianBlockTime = bitcoiny.getMedianBlockTime();
-			if (medianBlockTime <= lockTime)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				// We can't refund P2SH-A until lockTime-A has passed
+				if (NTP.getTime() <= lockTime * 1000L)
+					continue;
 
-			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));
+				// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
+				int medianBlockTime = bitcoiny.getMedianBlockTime();
+				if (medianBlockTime <= lockTime)
+					continue;
 
-			// 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);
+				// 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;
 
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-					// Still waiting for P2SH-A to be funded...
-					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				// 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));
 
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					// Too late!
-					return false;
+				switch (htlcStatusA) {
+					case UNFUNDED:
+					case FUNDING_IN_PROGRESS:
+						// Still waiting for P2SH-A to be funded...
+						continue;
 
-				case FUNDED:{
-					Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-					ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-					List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
+					case REDEEM_IN_PROGRESS:
+					case REDEEMED:
+					case REFUND_IN_PROGRESS:
+					case REFUNDED:
+						// Too late!
+						continue;
 
-					// 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);
+					case FUNDED: {
+						Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 
-					Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
-							fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
+						if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+							// Pirate Chain custom integration
 
-					bitcoiny.broadcastTransaction(p2shRefundTransaction);
-					return true;
+							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);
+						}
+
+						return true;
+					}
 				}
 			}
 

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

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainLitecoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Litecoin block height",
+		description = "Returns the height of the most recent block in the Litecoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getLitecoinHeight() {
+		Litecoin litecoin = Litecoin.getInstance();
+
+		try {
+			Integer height = litecoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainLitecoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = litecoin.getWalletBalanceFromTransactions(key58);
+			Long balance = litecoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainLitecoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address 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 String getUnusedLitecoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Litecoin litecoin = Litecoin.getInstance();
+
+		if (!litecoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return litecoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

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

@@ -0,0 +1,261 @@
+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.GET;
+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;
+
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current PirateChain block height",
+		description = "Returns the height of the most recent block in the PirateChain chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getPirateChainHeight() {
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			Integer height = pirateChain.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
+	@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/CrossChainRavencoinResource.java

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainRavencoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Ravencoin block height",
+		description = "Returns the height of the most recent block in the Ravencoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getRavencoinHeight() {
+		Ravencoin ravencoin = Ravencoin.getInstance();
+
+		try {
+			Integer height = ravencoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainRavencoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = ravencoin.getWalletBalanceFromTransactions(key58);
+			Long balance = ravencoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainRavencoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address 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 String getUnusedRavencoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Ravencoin ravencoin = Ravencoin.getInstance();
+
+		if (!ravencoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return ravencoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

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

@@ -115,6 +115,9 @@ public class CrossChainResource {
 				crossChainTrades.sort((a, b) -> Longs.compare(a.creationTimestamp, b.creationTimestamp));
 			}
 
+			// Remove any trades that have had too many failures
+			crossChainTrades = TradeBot.getInstance().removeFailedTrades(repository, crossChainTrades);
+
 			if (limit != null && limit > 0) {
 				// Make sure to not return more than the limit
 				int upperLimit = Math.min(limit, crossChainTrades.size());
@@ -129,6 +132,64 @@ public class CrossChainResource {
 		}
 	}
 
+	@GET
+	@Path("/tradeoffers/hidden")
+	@Operation(
+			summary = "Find cross-chain trade offers that have been hidden due to too many failures",
+			responses = {
+					@ApiResponse(
+							content = @Content(
+									array = @ArraySchema(
+											schema = @Schema(
+													implementation = CrossChainTradeData.class
+											)
+									)
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.REPOSITORY_ISSUE})
+	public List<CrossChainTradeData> getHiddenTradeOffers(
+			@Parameter(
+					description = "Limit to specific blockchain",
+					example = "LITECOIN",
+					schema = @Schema(implementation = SupportedBlockchain.class)
+			) @QueryParam("foreignBlockchain") SupportedBlockchain foreignBlockchain) {
+
+		final boolean isExecutable = true;
+		List<CrossChainTradeData> crossChainTrades = new ArrayList<>();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			Map<ByteArray, Supplier<ACCT>> acctsByCodeHash = SupportedBlockchain.getFilteredAcctMap(foreignBlockchain);
+
+			for (Map.Entry<ByteArray, Supplier<ACCT>> acctInfo : acctsByCodeHash.entrySet()) {
+				byte[] codeHash = acctInfo.getKey().value;
+				ACCT acct = acctInfo.getValue().get();
+
+				List<ATData> atsData = repository.getATRepository().getATsByFunctionality(codeHash, isExecutable, null, null, null);
+
+				for (ATData atData : atsData) {
+					CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atData);
+					if (crossChainTradeData.mode == AcctMode.OFFERING) {
+						crossChainTrades.add(crossChainTradeData);
+					}
+				}
+			}
+
+			// Sort the trades by timestamp
+			crossChainTrades.sort((a, b) -> Longs.compare(a.creationTimestamp, b.creationTimestamp));
+
+			// Remove trades that haven't failed
+			crossChainTrades.removeIf(t -> !TradeBot.getInstance().isFailedTrade(repository, t));
+
+			crossChainTrades.stream().forEach(CrossChainResource::decorateTradeDataWithPresence);
+
+			return crossChainTrades;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@GET
 	@Path("/trade/{ataddress}")
 	@Operation(

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

@@ -11,6 +11,7 @@ import io.swagger.v3.oas.annotations.security.SecurityRequirement;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
@@ -38,10 +39,14 @@ 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.MessageTransactionData;
+import org.qortal.data.transaction.TransactionData;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
+import org.qortal.transaction.Transaction;
 import org.qortal.utils.Base58;
+import org.qortal.utils.NTP;
 
 @Path("/crosschain/tradebot")
 @Tag(name = "Cross-Chain (Trade-Bot)")
@@ -137,7 +142,8 @@ 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 +159,7 @@ 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 +204,8 @@ 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
@@ -220,6 +227,17 @@ public class CrossChainTradeBotResource {
 			if (crossChainTradeData.mode != AcctMode.OFFERING)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
+			// Check if there is a buy or a cancel request in progress for this trade
+			List<Transaction.TransactionType> txTypes = List.of(Transaction.TransactionType.MESSAGE);
+			List<TransactionData> unconfirmed = repository.getTransactionRepository().getUnconfirmedTransactions(txTypes, null, 0, 0, false);
+			for (TransactionData  transactionData : unconfirmed) {
+				MessageTransactionData messageTransactionData = (MessageTransactionData) transactionData;
+				if (Objects.equals(messageTransactionData.getRecipient(), atAddress)) {
+					// There is a pending request for this trade, so block this buy attempt to reduce the risk of refunds
+					throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Trade has an existing buy request or is pending cancellation.");
+				}
+			}
+
 			AcctTradeBot.ResponseResult result = TradeBot.getInstance().startResponse(repository, atData, acct, crossChainTradeData,
 					tradeBotRespondRequest.foreignKey, tradeBotRespondRequest.receivingAddress);
 
@@ -237,7 +255,7 @@ 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/DeveloperResource.java

@@ -0,0 +1,96 @@
+package org.qortal.api.resource;
+
+import io.swagger.v3.oas.annotations.Operation;
+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.tags.Tag;
+import org.qortal.api.ApiError;
+import org.qortal.api.ApiErrors;
+import org.qortal.api.ApiExceptionFactory;
+import org.qortal.controller.DevProxyManager;
+import org.qortal.repository.DataException;
+
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+
+
+@Path("/developer")
+@Tag(name = "Developer Tools")
+public class DeveloperResource {
+
+	@Context HttpServletRequest request;
+	@Context HttpServletResponse response;
+	@Context ServletContext context;
+
+
+	@POST
+	@Path("/proxy/start")
+	@Operation(
+			summary = "Start proxy server, for real time QDN app/website development",
+			requestBody = @RequestBody(
+					description = "Host and port of source webserver to be proxied",
+					required = true,
+					content = @Content(
+							mediaType = MediaType.TEXT_PLAIN,
+							schema = @Schema(
+									type = "string",
+									example = "127.0.0.1:5173"
+							)
+					)
+			),
+			responses = {
+					@ApiResponse(
+							description = "Port number of running server",
+							content = @Content(
+									mediaType = MediaType.TEXT_PLAIN,
+									schema = @Schema(
+											type = "number"
+									)
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_CRITERIA})
+	public Integer startProxy(String sourceHostAndPort) {
+		// TODO: API key
+		DevProxyManager devProxyManager = DevProxyManager.getInstance();
+		try {
+			devProxyManager.setSourceHostAndPort(sourceHostAndPort);
+			devProxyManager.start();
+			return devProxyManager.getPort();
+
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, e.getMessage());
+		}
+	}
+
+	@POST
+	@Path("/proxy/stop")
+	@Operation(
+			summary = "Stop proxy server",
+			responses = {
+					@ApiResponse(
+							description = "true if stopped",
+							content = @Content(
+									mediaType = MediaType.TEXT_PLAIN,
+									schema = @Schema(
+											type = "boolean"
+									)
+							)
+					)
+			}
+	)
+	public boolean stopProxy() {
+		DevProxyManager devProxyManager = DevProxyManager.getInstance();
+		devProxyManager.stop();
+		return !devProxyManager.isRunning();
+	}
+
+}

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

@@ -47,6 +47,7 @@ import org.qortal.transform.transaction.RegisterNameTransactionTransformer;
 import org.qortal.transform.transaction.SellNameTransactionTransformer;
 import org.qortal.transform.transaction.UpdateNameTransactionTransformer;
 import org.qortal.utils.Base58;
+import org.qortal.utils.Unicode;
 
 @Path("/names")
 @Tag(name = "Names")
@@ -63,19 +64,19 @@ public class NamesResource {
 				description = "registered name info",
 				content = @Content(
 					mediaType = MediaType.APPLICATION_JSON,
-					array = @ArraySchema(schema = @Schema(implementation = NameSummary.class))
+					array = @ArraySchema(schema = @Schema(implementation = NameData.class))
 				)
 			)
 		}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<NameSummary> getAllNames(@Parameter(ref = "limit") @QueryParam("limit") Integer limit, @Parameter(ref = "offset") @QueryParam("offset") Integer offset,
-			@Parameter(ref="reverse") @QueryParam("reverse") Boolean reverse) {
+	public List<NameData> getAllNames(@Parameter(description = "Return only names registered or updated after timestamp") @QueryParam("after") Long after,
+										 @Parameter(ref = "limit") @QueryParam("limit") Integer limit,
+										 @Parameter(ref = "offset") @QueryParam("offset") Integer offset,
+										 @Parameter(ref="reverse") @QueryParam("reverse") Boolean reverse) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			List<NameData> names = repository.getNameRepository().getAllNames(limit, offset, reverse);
 
-			// Convert to summary
-			return names.stream().map(NameSummary::new).collect(Collectors.toList());
+			return repository.getNameRepository().getAllNames(after, limit, offset, reverse);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
@@ -135,12 +136,13 @@ public class NamesResource {
 	public NameData getName(@PathParam("name") String name) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			NameData nameData;
+			String reducedName = Unicode.sanitize(name);
 
 			if (Settings.getInstance().isLite()) {
 				nameData = LiteNode.getInstance().fetchNameData(name);
 			}
 			else {
-				nameData = repository.getNameRepository().fromName(name);
+				nameData = repository.getNameRepository().fromReducedName(reducedName);
 			}
 
 			if (nameData == null) {
@@ -155,6 +157,41 @@ public class NamesResource {
 		}
 	}
 
+	@GET
+	@Path("/search")
+	@Operation(
+			summary = "Search registered names",
+			responses = {
+					@ApiResponse(
+							description = "registered name info",
+							content = @Content(
+									mediaType = MediaType.APPLICATION_JSON,
+									array = @ArraySchema(schema = @Schema(implementation = NameData.class))
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.NAME_UNKNOWN, ApiError.REPOSITORY_ISSUE})
+	public List<NameData> searchNames(@QueryParam("query") String query,
+									  @Parameter(description = "Prefix only (if true, only the beginning of the name is matched)") @QueryParam("prefix") Boolean prefixOnly,
+									  @Parameter(ref = "limit") @QueryParam("limit") Integer limit,
+									  @Parameter(ref = "offset") @QueryParam("offset") Integer offset,
+									  @Parameter(ref="reverse") @QueryParam("reverse") Boolean reverse) {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			if (query == null) {
+				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Missing query");
+			}
+
+			boolean usePrefixOnly = Boolean.TRUE.equals(prefixOnly);
+
+			return repository.getNameRepository().searchNames(query, usePrefixOnly, limit, offset, reverse);
+		} catch (ApiException e) {
+			throw e;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 
 	@POST
 	@Path("/register")
@@ -410,4 +447,4 @@ public class NamesResource {
 		}
 	}
 
-}
+}

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

@@ -0,0 +1,258 @@
+package org.qortal.api.resource;
+
+import io.swagger.v3.oas.annotations.Operation;
+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.tags.Tag;
+import org.qortal.api.ApiError;
+import org.qortal.api.ApiErrors;
+import org.qortal.api.ApiExceptionFactory;
+import org.qortal.data.transaction.CreatePollTransactionData;
+import org.qortal.data.transaction.PaymentTransactionData;
+import org.qortal.data.transaction.VoteOnPollTransactionData;
+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.transform.transaction.CreatePollTransactionTransformer;
+import org.qortal.transform.transaction.PaymentTransactionTransformer;
+import org.qortal.transform.transaction.VoteOnPollTransactionTransformer;
+import org.qortal.utils.Base58;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+
+import io.swagger.v3.oas.annotations.Parameter;
+import io.swagger.v3.oas.annotations.media.ArraySchema;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+import javax.ws.rs.GET;
+import javax.ws.rs.PathParam;
+import javax.ws.rs.QueryParam;
+import org.qortal.api.ApiException;
+import org.qortal.api.model.PollVotes;
+import org.qortal.data.voting.PollData;
+import org.qortal.data.voting.PollOptionData;
+import org.qortal.data.voting.VoteOnPollData;
+
+@Path("/polls")
+@Tag(name = "Polls")
+public class PollsResource {
+    @Context
+    HttpServletRequest request;
+
+    @GET
+    @Operation(
+            summary = "List all polls",
+            responses = {
+                    @ApiResponse(
+                            description = "poll info",
+                            content = @Content(
+                                    mediaType = MediaType.APPLICATION_JSON,
+                                    array = @ArraySchema(schema = @Schema(implementation = PollData.class))
+                            )
+                    )
+            }
+    )
+    @ApiErrors({ApiError.REPOSITORY_ISSUE})
+    public List<PollData> getAllPolls(@Parameter(
+            ref = "limit"
+    ) @QueryParam("limit") Integer limit, @Parameter(
+            ref = "offset"
+    ) @QueryParam("offset") Integer offset, @Parameter(
+            ref = "reverse"
+    ) @QueryParam("reverse") Boolean reverse) {
+            try (final Repository repository = RepositoryManager.getRepository()) {
+		    List<PollData> allPollData = repository.getVotingRepository().getAllPolls(limit, offset, reverse);
+		    return allPollData;
+            } catch (DataException e) {
+		    throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+            }
+    }
+
+    @GET
+    @Path("/{pollName}")
+    @Operation(
+            summary = "Info on poll",
+            responses = {
+                    @ApiResponse(
+                            description = "poll info",
+                            content = @Content(
+                                    mediaType = MediaType.APPLICATION_JSON,
+                                    schema = @Schema(implementation = PollData.class)
+                            )
+                    )
+            }
+    )
+    @ApiErrors({ApiError.REPOSITORY_ISSUE})
+    public PollData getPollData(@PathParam("pollName") String pollName) {
+            try (final Repository repository = RepositoryManager.getRepository()) {
+                    PollData pollData = repository.getVotingRepository().fromPollName(pollName);
+                    if (pollData == null)
+                            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.POLL_NO_EXISTS);
+
+                    return pollData;
+            } catch (ApiException e) {
+                    throw e;
+            } catch (DataException e) {
+                    throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+            }
+    }
+
+    @GET
+    @Path("/votes/{pollName}")
+    @Operation(
+            summary = "Votes on poll",
+            responses = {
+                    @ApiResponse(
+                            description = "poll votes",
+                            content = @Content(
+                                    mediaType = MediaType.APPLICATION_JSON,
+                                    schema = @Schema(implementation = PollVotes.class)
+                            )
+                    )
+            }
+    )
+    @ApiErrors({ApiError.REPOSITORY_ISSUE})
+    public PollVotes getPollVotes(@PathParam("pollName") String pollName, @QueryParam("onlyCounts") Boolean onlyCounts) {
+            try (final Repository repository = RepositoryManager.getRepository()) {
+                    PollData pollData = repository.getVotingRepository().fromPollName(pollName);
+                    if (pollData == null)
+                            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.POLL_NO_EXISTS);
+
+                    List<VoteOnPollData> votes = repository.getVotingRepository().getVotes(pollName);
+
+                    // Initialize map for counting votes
+                    Map<String, Integer> voteCountMap = new HashMap<>();
+                    for (PollOptionData optionData : pollData.getPollOptions()) {
+                            voteCountMap.put(optionData.getOptionName(), 0);
+                    }
+
+                    int totalVotes = 0;
+                    for (VoteOnPollData vote : votes) {
+                            String selectedOption = pollData.getPollOptions().get(vote.getOptionIndex()).getOptionName();
+                            if (voteCountMap.containsKey(selectedOption)) {
+                                    voteCountMap.put(selectedOption, voteCountMap.get(selectedOption) + 1);
+                                    totalVotes++;
+                            }
+                    }
+
+                    // Convert map to list of VoteInfo
+                    List<PollVotes.OptionCount> voteCounts = voteCountMap.entrySet().stream()
+                        .map(entry -> new PollVotes.OptionCount(entry.getKey(), entry.getValue()))
+                        .collect(Collectors.toList());
+    
+                    if (onlyCounts != null && onlyCounts) {
+                        return new PollVotes(null, totalVotes, voteCounts);
+                    } else {
+                        return new PollVotes(votes, totalVotes, voteCounts);
+                    }
+            } catch (ApiException e) {
+                    throw e;
+            } catch (DataException e) {
+                    throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+            }
+    }
+
+    @POST
+    @Path("/create")
+    @Operation(
+            summary = "Build raw, unsigned, CREATE_POLL transaction",
+            requestBody = @RequestBody(
+                    required = true,
+                    content = @Content(
+                            mediaType = MediaType.APPLICATION_JSON,
+                            schema = @Schema(
+                                    implementation = CreatePollTransactionData.class
+                            )
+                    )
+            ),
+            responses = {
+                    @ApiResponse(
+                            description = "raw, unsigned, CREATE_POLL transaction encoded in Base58",
+                            content = @Content(
+                                    mediaType = MediaType.TEXT_PLAIN,
+                                    schema = @Schema(
+                                            type = "string"
+                                    )
+                            )
+                    )
+            }
+    )
+    @ApiErrors({ApiError.NON_PRODUCTION, ApiError.TRANSACTION_INVALID, ApiError.TRANSFORMATION_ERROR, ApiError.REPOSITORY_ISSUE})
+    public String CreatePoll(CreatePollTransactionData transactionData) {
+        if (Settings.getInstance().isApiRestricted())
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.NON_PRODUCTION);
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            Transaction transaction = Transaction.fromData(repository, transactionData);
+
+            Transaction.ValidationResult result = transaction.isValidUnconfirmed();
+            if (result != Transaction.ValidationResult.OK)
+                throw TransactionsResource.createTransactionInvalidException(request, result);
+
+            byte[] bytes = CreatePollTransactionTransformer.toBytes(transactionData);
+            return Base58.encode(bytes);
+        } catch (TransformationException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.TRANSFORMATION_ERROR, e);
+        } catch (DataException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+        }
+    }
+
+    @POST
+    @Path("/vote")
+    @Operation(
+            summary = "Build raw, unsigned, VOTE_ON_POLL transaction",
+            requestBody = @RequestBody(
+                    required = true,
+                    content = @Content(
+                            mediaType = MediaType.APPLICATION_JSON,
+                            schema = @Schema(
+                                    implementation = VoteOnPollTransactionData.class
+                            )
+                    )
+            ),
+            responses = {
+                    @ApiResponse(
+                            description = "raw, unsigned, VOTE_ON_POLL transaction encoded in Base58",
+                            content = @Content(
+                                    mediaType = MediaType.TEXT_PLAIN,
+                                    schema = @Schema(
+                                            type = "string"
+                                    )
+                            )
+                    )
+            }
+    )
+    @ApiErrors({ApiError.NON_PRODUCTION, ApiError.TRANSACTION_INVALID, ApiError.TRANSFORMATION_ERROR, ApiError.REPOSITORY_ISSUE})
+    public String VoteOnPoll(VoteOnPollTransactionData transactionData) {
+        if (Settings.getInstance().isApiRestricted())
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.NON_PRODUCTION);
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            Transaction transaction = Transaction.fromData(repository, transactionData);
+
+            Transaction.ValidationResult result = transaction.isValidUnconfirmed();
+            if (result != Transaction.ValidationResult.OK)
+                throw TransactionsResource.createTransactionInvalidException(request, result);
+
+            byte[] bytes = VoteOnPollTransactionTransformer.toBytes(transactionData);
+            return Base58.encode(bytes);
+        } catch (TransformationException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.TRANSFORMATION_ERROR, e);
+        } catch (DataException e) {
+            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+        }
+    }
+    
+}

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

@@ -0,0 +1,70 @@
+package org.qortal.api.resource;
+
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.media.Content;
+import io.swagger.v3.oas.annotations.media.Schema;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.api.*;
+import org.qortal.block.BlockChain;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.repository.RepositoryManager;
+import org.qortal.utils.Amounts;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.*;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+import java.math.BigDecimal;
+import java.util.List;
+
+@Path("/stats")
+@Tag(name = "Stats")
+public class StatsResource {
+
+	private static final Logger LOGGER = LogManager.getLogger(StatsResource.class);
+
+
+	@Context
+	HttpServletRequest request;
+
+	@GET
+	@Path("/supply/circulating")
+	@Operation(
+		summary = "Fetch circulating QORT supply",
+		responses = {
+			@ApiResponse(
+					description = "circulating supply of QORT",
+					content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string", format = "number"))
+			)
+		}
+	)
+	public BigDecimal circulatingSupply() {
+		long total = 0L;
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			int currentHeight = repository.getBlockRepository().getBlockchainHeight();
+
+			List<BlockChain.RewardByHeight> rewardsByHeight = BlockChain.getInstance().getBlockRewardsByHeight();
+			int rewardIndex = rewardsByHeight.size() - 1;
+			BlockChain.RewardByHeight rewardInfo = rewardsByHeight.get(rewardIndex);
+
+			for (int height = currentHeight; height > 1; --height) {
+				if (height < rewardInfo.height) {
+					--rewardIndex;
+					rewardInfo = rewardsByHeight.get(rewardIndex);
+				}
+
+				total += rewardInfo.reward;
+			}
+
+			return Amounts.toBigDecimal(total);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+}

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

@@ -9,6 +9,8 @@ import io.swagger.v3.oas.annotations.parameters.RequestBody;
 import io.swagger.v3.oas.annotations.responses.ApiResponse;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
+import java.io.IOException;
+import java.io.StringWriter;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.util.ArrayList;
@@ -18,19 +20,12 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReentrantLock;
 
 import javax.servlet.http.HttpServletRequest;
-import javax.ws.rs.GET;
-import javax.ws.rs.POST;
-import javax.ws.rs.Path;
-import javax.ws.rs.PathParam;
-import javax.ws.rs.QueryParam;
+import javax.ws.rs.*;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 
 import org.qortal.account.PrivateKeyAccount;
-import org.qortal.api.ApiError;
-import org.qortal.api.ApiErrors;
-import org.qortal.api.ApiException;
-import org.qortal.api.ApiExceptionFactory;
+import org.qortal.api.*;
 import org.qortal.api.model.SimpleTransactionSignRequest;
 import org.qortal.controller.Controller;
 import org.qortal.controller.LiteNode;
@@ -220,10 +215,25 @@ public class TransactionsResource {
 		}
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			if (repository.getBlockRepository().getHeightFromSignature(signature) == 0)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCK_UNKNOWN);
+			// Check if the block exists in either the database or archive
+			int height = repository.getBlockRepository().getHeightFromSignature(signature);
+			if (height == 0) {
+				height = repository.getBlockArchiveRepository().getHeightFromSignature(signature);
+				if (height == 0) {
+					// Not found in either the database or archive
+					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.BLOCK_UNKNOWN);
+				}
+			}
 
-			return repository.getBlockRepository().getTransactionsFromSignature(signature, limit, offset, reverse);
+			List<byte[]> signatures = repository.getTransactionRepository().getSignaturesMatchingCriteria(null, null, height, height);
+
+			// Expand signatures to transactions
+			List<TransactionData> transactions = new ArrayList<>(signatures.size());
+			for (byte[] s : signatures) {
+				transactions.add(repository.getTransactionRepository().fromSignature(s));
+			}
+
+			return transactions;
 		} catch (ApiException e) {
 			throw e;
 		} catch (DataException e) {
@@ -709,7 +719,7 @@ public class TransactionsResource {
 		),
 		responses = {
 			@ApiResponse(
-				description = "true if accepted, false otherwise",
+				description = "For API version 1, this returns true if accepted.\nFor API version 2, the transactionData is returned as a JSON string if accepted.",
 				content = @Content(
 					mediaType = MediaType.TEXT_PLAIN,
 					schema = @Schema(
@@ -722,10 +732,12 @@ public class TransactionsResource {
 	@ApiErrors({
 		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
+	public String processTransaction(String rawBytes58, @HeaderParam(ApiService.API_VERSION_HEADER) String apiVersionHeader) {
+		int apiVersion = ApiService.getApiVersion(request);
+
+		// 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);
 
@@ -748,7 +760,7 @@ 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 {
@@ -759,13 +771,27 @@ public class TransactionsResource {
 				blockchainLock.unlock();
 			}
 
-			return "true";
+			switch (apiVersion) {
+				case 1:
+					return "true";
+
+				case 2:
+				default:
+					// Marshall transactionData to string
+					StringWriter stringWriter = new StringWriter();
+					ApiRequest.marshall(stringWriter, transactionData);
+					return stringWriter.toString();
+			}
+
+
 		} catch (NumberFormatException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_DATA, e);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		} catch (InterruptedException e) {
 			throw createTransactionInvalidException(request, ValidationResult.NO_BLOCKCHAIN_LOCK);
+		} catch (IOException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.TRANSFORMATION_ERROR, e);
 		}
 	}
 

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

@@ -1,4 +1,4 @@
-package org.qortal.api.resource;
+package org.qortal.api.restricted.resource;
 
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
@@ -20,6 +20,7 @@ import java.time.LocalDate;
 import java.time.LocalTime;
 import java.time.OffsetDateTime;
 import java.time.ZoneOffset;
+import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -31,10 +32,13 @@ import javax.ws.rs.*;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 
+import org.apache.commons.lang3.reflect.FieldUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.core.LoggerContext;
 import org.apache.logging.log4j.core.appender.RollingFileAppender;
+import org.json.JSONArray;
+import org.json.JSONObject;
 import org.qortal.account.Account;
 import org.qortal.account.PrivateKeyAccount;
 import org.qortal.api.*;
@@ -42,9 +46,11 @@ import org.qortal.api.model.ActivitySummary;
 import org.qortal.api.model.NodeInfo;
 import org.qortal.api.model.NodeStatus;
 import org.qortal.block.BlockChain;
+import org.qortal.controller.AutoUpdate;
 import org.qortal.controller.Controller;
 import org.qortal.controller.Synchronizer;
 import org.qortal.controller.Synchronizer.SynchronizationResult;
+import org.qortal.controller.repository.BlockArchiveRebuilder;
 import org.qortal.data.account.MintingAccountData;
 import org.qortal.data.account.RewardShareData;
 import org.qortal.network.Network;
@@ -125,12 +131,12 @@ public class AdminResource {
 	}
 
 	private String getNodeType() {
-		if (Settings.getInstance().isTopOnly()) {
-			return "topOnly";
-		}
-		else if (Settings.getInstance().isLite()) {
+		if (Settings.getInstance().isLite()) {
 			return "lite";
 		}
+		else if (Settings.getInstance().isTopOnly()) {
+			return "topOnly";
+		}
 		else {
 			return "full";
 		}
@@ -152,6 +158,53 @@ public class AdminResource {
 		return nodeStatus;
 	}
 
+	@GET
+	@Path("/settings")
+	@Operation(
+		summary = "Fetch node settings",
+		responses = {
+			@ApiResponse(
+				content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = Settings.class))
+			)
+		}
+	)
+	public Settings settings() {
+		Settings nodeSettings = Settings.getInstance();
+
+		return nodeSettings;
+	}
+
+	@GET
+	@Path("/settings/{setting}")
+	@Operation(
+			summary = "Fetch a single node setting",
+			responses = {
+					@ApiResponse(
+							content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string"))
+					)
+			}
+	)
+	public String setting(@PathParam("setting") String setting) {
+		try {
+			Object settingValue = FieldUtils.readField(Settings.getInstance(), setting, true);
+			if (settingValue == null) {
+				return "null";
+			}
+			else if (settingValue instanceof String[]) {
+				JSONArray array = new JSONArray(settingValue);
+				return array.toString(4);
+			}
+			else if (settingValue instanceof List) {
+				JSONArray array = new JSONArray((List<Object>) settingValue);
+				return array.toString(4);
+			}
+
+			return settingValue.toString();
+		} catch (IllegalAccessException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA, e);
+		}
+	}
+
 	@GET
 	@Path("/stop")
 	@Operation(
@@ -182,6 +235,37 @@ public class AdminResource {
 		return "true";
 	}
 
+	@GET
+	@Path("/restart")
+	@Operation(
+		summary = "Restart",
+		description = "Restart",
+		responses = {
+			@ApiResponse(
+				description = "\"true\"",
+				content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string"))
+			)
+		}
+	)
+	@SecurityRequirement(name = "apiKey")
+	public String restart(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+		Security.checkApiCallAllowed(request);
+
+		new Thread(() -> {
+			// Short sleep to allow HTTP response body to be emitted
+			try {
+				Thread.sleep(1000);
+			} catch (InterruptedException e) {
+				// Not important
+			}
+
+			AutoUpdate.attemptRestart();
+
+		}).start();
+
+		return "true";
+	}
+
 	@GET
 	@Path("/summary")
 	@Operation(
@@ -222,6 +306,42 @@ public class AdminResource {
 		}
 	}
 
+	@GET
+	@Path("/summary/alltime")
+	@Operation(
+			summary = "Summary of activity since genesis",
+			responses = {
+					@ApiResponse(
+							content = @Content(schema = @Schema(implementation = ActivitySummary.class))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public ActivitySummary allTimeSummary(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+		Security.checkApiCallAllowed(request);
+
+		ActivitySummary summary = new ActivitySummary();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			int startHeight = 1;
+			long start = repository.getBlockRepository().fromHeight(startHeight).getTimestamp();
+			int endHeight = repository.getBlockRepository().getBlockchainHeight();
+
+			summary.setBlockCount(endHeight - startHeight);
+
+			summary.setTransactionCountByType(repository.getTransactionRepository().getTransactionSummary(startHeight + 1, endHeight));
+
+			summary.setAssetsIssued(repository.getAssetRepository().getRecentAssetIds(start).size());
+
+			summary.setNamesRegistered (repository.getNameRepository().getRecentNames(start).size());
+
+			return summary;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@GET
 	@Path("/enginestats")
 	@Operation(
@@ -698,6 +818,64 @@ public class AdminResource {
 		}
 	}
 
+	@POST
+	@Path("/repository/archive/rebuild")
+	@Operation(
+			summary = "Rebuild archive",
+			description = "Rebuilds archive files, using the specified serialization version",
+			requestBody = @RequestBody(
+					required = true,
+					content = @Content(
+							mediaType = MediaType.TEXT_PLAIN,
+							schema = @Schema(
+									type = "number", example = "2"
+							)
+					)
+			),
+			responses = {
+					@ApiResponse(
+							description = "\"true\"",
+							content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string"))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String rebuildArchive(@HeaderParam(Security.API_KEY_HEADER) String apiKey, Integer serializationVersion) {
+		Security.checkApiCallAllowed(request);
+
+		// Default serialization version to value specified in settings
+		if (serializationVersion == null) {
+			serializationVersion = Settings.getInstance().getDefaultArchiveVersion();
+		}
+
+		try {
+			// We don't actually need to lock the blockchain here, but we'll do it anyway so that
+			// the node can focus on rebuilding rather than synchronizing / minting.
+			ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+
+			blockchainLock.lockInterruptibly();
+
+			try {
+				BlockArchiveRebuilder blockArchiveRebuilder = new BlockArchiveRebuilder(serializationVersion);
+				blockArchiveRebuilder.start();
+
+				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 rebuild
+			return "false";
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@DELETE
 	@Path("/repository")
 	@Operation(
@@ -728,6 +906,49 @@ 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/restricted/resource/BootstrapResource.java

@@ -1,4 +1,4 @@
-package org.qortal.api.resource;
+package org.qortal.api.restricted.resource;
 
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.media.Content;
@@ -60,7 +60,7 @@ public class BootstrapResource {
 			bootstrap.validateBlockchain();
 			return bootstrap.create();
 
-		} catch (DataException | InterruptedException | IOException e) {
+		} catch (Exception e) {
 			LOGGER.info("Unable to create bootstrap", e);
 			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
 		}

src/main/java/org/qortal/api/restricted/resource/RenderResource.java

@@ -1,4 +1,4 @@
-package org.qortal.api.resource;
+package org.qortal.api.restricted.resource;
 
 import javax.servlet.ServletContext;
 import javax.servlet.http.HttpServletRequest;
@@ -8,7 +8,6 @@ import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 import java.io.*;
 import java.nio.file.Paths;
-import java.util.Map;
 
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.media.Content;
@@ -28,8 +27,8 @@ import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.controller.arbitrary.ArbitraryDataRenderManager;
 import org.qortal.data.transaction.ArbitraryTransactionData.*;
 import org.qortal.repository.DataException;
-import org.qortal.settings.Settings;
 import org.qortal.arbitrary.ArbitraryDataFile.*;
+import org.qortal.settings.Settings;
 import org.qortal.utils.Base58;
 
 
@@ -43,60 +42,6 @@ public class RenderResource {
     @Context HttpServletResponse response;
     @Context ServletContext context;
 
-    @POST
-    @Path("/preview")
-    @Operation(
-            summary = "Generate preview URL based on a user-supplied path and service",
-            requestBody = @RequestBody(
-                    required = true,
-                    content = @Content(
-                            mediaType = MediaType.TEXT_PLAIN,
-                            schema = @Schema(
-                                    type = "string", example = "/Users/user/Documents/MyStaticWebsite"
-                            )
-                    )
-            ),
-            responses = {
-                    @ApiResponse(
-                            description = "a temporary URL to preview the website",
-                            content = @Content(
-                                    mediaType = MediaType.TEXT_PLAIN,
-                                    schema = @Schema(
-                                            type = "string"
-                                    )
-                            )
-                    )
-            }
-    )
-    @SecurityRequirement(name = "apiKey")
-    public String preview(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String directoryPath) {
-        Security.checkApiCallAllowed(request);
-        Method method = Method.PUT;
-        Compression compression = Compression.ZIP;
-
-        ArbitraryDataWriter arbitraryDataWriter = new ArbitraryDataWriter(Paths.get(directoryPath),
-                null, Service.WEBSITE, null, method, compression,
-                null, null, null, null);
-        try {
-            arbitraryDataWriter.save();
-        } catch (IOException | DataException | InterruptedException | MissingDataException e) {
-            LOGGER.info("Unable to create arbitrary data file: {}", e.getMessage());
-            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE);
-        } catch (RuntimeException e) {
-            LOGGER.info("Unable to create arbitrary data file: {}", e.getMessage());
-            throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_DATA);
-        }
-
-        ArbitraryDataFile arbitraryDataFile = arbitraryDataWriter.getArbitraryDataFile();
-        if (arbitraryDataFile != null) {
-            String digest58 = arbitraryDataFile.digest58();
-            if (digest58 != null) {
-                return "http://localhost:12393/render/hash/" + digest58 + "?secret=" + Base58.encode(arbitraryDataFile.getSecret());
-            }
-        }
-        return "Unable to generate preview URL";
-    }
-
     @POST
     @Path("/authorize/{resourceId}")
     @SecurityRequirement(name = "apiKey")
@@ -140,8 +85,10 @@ public class RenderResource {
     @SecurityRequirement(name = "apiKey")
     public HttpServletResponse getIndexBySignature(@PathParam("signature") String signature,
                                                    @QueryParam("theme") String theme) {
-        Security.requirePriorAuthorization(request, signature, Service.WEBSITE, null);
-        return this.get(signature, ResourceIdType.SIGNATURE, null, "/", null, "/render/signature", true, true, theme);
+        if (!Settings.getInstance().isQDNAuthBypassEnabled())
+            Security.requirePriorAuthorization(request, signature, Service.WEBSITE, null);
+
+        return this.get(signature, ResourceIdType.SIGNATURE, null, null, "/", null, "/render/signature", true, true, theme);
     }
 
     @GET
@@ -149,8 +96,10 @@ public class RenderResource {
     @SecurityRequirement(name = "apiKey")
     public HttpServletResponse getPathBySignature(@PathParam("signature") String signature, @PathParam("path") String inPath,
                                                   @QueryParam("theme") String theme) {
-        Security.requirePriorAuthorization(request, signature, Service.WEBSITE, null);
-        return this.get(signature, ResourceIdType.SIGNATURE, null, inPath,null, "/render/signature", true, true, theme);
+        if (!Settings.getInstance().isQDNAuthBypassEnabled())
+            Security.requirePriorAuthorization(request, signature, Service.WEBSITE, null);
+
+        return this.get(signature, ResourceIdType.SIGNATURE, null, null, inPath,null, "/render/signature", true, true, theme);
     }
 
     @GET
@@ -158,8 +107,10 @@ public class RenderResource {
     @SecurityRequirement(name = "apiKey")
     public HttpServletResponse getIndexByHash(@PathParam("hash") String hash58, @QueryParam("secret") String secret58,
                                               @QueryParam("theme") String theme) {
-        Security.requirePriorAuthorization(request, hash58, Service.WEBSITE, null);
-        return this.get(hash58, ResourceIdType.FILE_HASH, Service.WEBSITE, "/", secret58, "/render/hash", true, false, theme);
+        if (!Settings.getInstance().isQDNAuthBypassEnabled())
+            Security.requirePriorAuthorization(request, hash58, Service.WEBSITE, null);
+
+        return this.get(hash58, ResourceIdType.FILE_HASH, Service.ARBITRARY_DATA, null, "/", secret58, "/render/hash", true, false, theme);
     }
 
     @GET
@@ -168,8 +119,10 @@ public class RenderResource {
     public HttpServletResponse getPathByHash(@PathParam("hash") String hash58, @PathParam("path") String inPath,
                                              @QueryParam("secret") String secret58,
                                              @QueryParam("theme") String theme) {
-        Security.requirePriorAuthorization(request, hash58, Service.WEBSITE, null);
-        return this.get(hash58, ResourceIdType.FILE_HASH, Service.WEBSITE, inPath, secret58, "/render/hash", true, false, theme);
+        if (!Settings.getInstance().isQDNAuthBypassEnabled())
+            Security.requirePriorAuthorization(request, hash58, Service.WEBSITE, null);
+
+        return this.get(hash58, ResourceIdType.FILE_HASH, Service.ARBITRARY_DATA, null, inPath, secret58, "/render/hash", true, false, theme);
     }
 
     @GET
@@ -178,10 +131,13 @@ public class RenderResource {
     public HttpServletResponse getPathByName(@PathParam("service") Service service,
                                              @PathParam("name") String name,
                                              @PathParam("path") String inPath,
+                                             @QueryParam("identifier") String identifier,
                                              @QueryParam("theme") String theme) {
-        Security.requirePriorAuthorization(request, name, service, null);
+        if (!Settings.getInstance().isQDNAuthBypassEnabled())
+            Security.requirePriorAuthorization(request, name, service, null);
+
         String prefix = String.format("/render/%s", service);
-        return this.get(name, ResourceIdType.NAME, service, inPath, null, prefix, true, true, theme);
+        return this.get(name, ResourceIdType.NAME, service, identifier, inPath, null, prefix, true, true, theme);
     }
 
     @GET
@@ -189,19 +145,22 @@ public class RenderResource {
     @SecurityRequirement(name = "apiKey")
     public HttpServletResponse getIndexByName(@PathParam("service") Service service,
                                               @PathParam("name") String name,
+                                              @QueryParam("identifier") String identifier,
                                               @QueryParam("theme") String theme) {
-        Security.requirePriorAuthorization(request, name, service, null);
+        if (!Settings.getInstance().isQDNAuthBypassEnabled())
+            Security.requirePriorAuthorization(request, name, service, null);
+
         String prefix = String.format("/render/%s", service);
-        return this.get(name, ResourceIdType.NAME, service, "/", null, prefix, true, true, theme);
+        return this.get(name, ResourceIdType.NAME, service, identifier, "/", null, prefix, true, true, theme);
     }
 
 
 
-    private HttpServletResponse get(String resourceId, ResourceIdType resourceIdType, Service service, String inPath,
-                                    String secret58, String prefix, boolean usePrefix, boolean async, String theme) {
+    private HttpServletResponse get(String resourceId, ResourceIdType resourceIdType, Service service, String identifier,
+                                    String inPath, String secret58, String prefix, boolean includeResourceIdInPrefix, boolean async, String theme) {
 
-        ArbitraryDataRenderer renderer = new ArbitraryDataRenderer(resourceId, resourceIdType, service, inPath,
-                secret58, prefix, usePrefix, async, request, response, context);
+        ArbitraryDataRenderer renderer = new ArbitraryDataRenderer(resourceId, resourceIdType, service, identifier, inPath,
+                secret58, prefix, includeResourceIdInPrefix, async, "render", request, response, context);
 
         if (theme != null) {
             renderer.setTheme(theme);

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

@@ -2,7 +2,9 @@ package org.qortal.api.websocket;
 
 import java.io.IOException;
 import java.io.StringWriter;
+import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicReference;
 
 import org.eclipse.jetty.websocket.api.Session;
@@ -21,6 +23,8 @@ import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @WebSocket
 @SuppressWarnings("serial")
 public class ActiveChatsWebSocket extends ApiWebSocket {
@@ -62,7 +66,9 @@ public class ActiveChatsWebSocket extends ApiWebSocket {
 
 	@OnWebSocketMessage
 	public void onWebSocketMessage(Session session, String message) {
-		/* ignored */
+		if (Objects.equals(message, "ping")) {
+			session.getRemote().sendStringByFuture("pong");
+		}
 	}
 
 	private void onNotify(Session session, ChatTransactionData chatTransactionData, String ourAddress, AtomicReference<String> previousOutput) {
@@ -75,7 +81,7 @@ public class ActiveChatsWebSocket extends ApiWebSocket {
 		}
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			ActiveChats activeChats = repository.getChatRepository().getActiveChats(ourAddress);
+			ActiveChats activeChats = repository.getChatRepository().getActiveChats(ourAddress, getTargetEncoding(session));
 
 			StringWriter stringWriter = new StringWriter();
 
@@ -93,4 +99,12 @@ public class ActiveChatsWebSocket extends ApiWebSocket {
 		}
 	}
 
+	private Encoding getTargetEncoding(Session session) {
+		// Default to Base58 if not specified, for backwards support
+		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		List<String> encodingList = queryParams.get("encoding");
+		String encoding = (encodingList != null && encodingList.size() == 1) ? encodingList.get(0) : "BASE58";
+		return Encoding.valueOf(encoding);
+	}
+
 }

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

@@ -2,10 +2,7 @@ package org.qortal.api.websocket;
 
 import java.io.IOException;
 import java.io.StringWriter;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import org.eclipse.jetty.websocket.api.Session;
 import org.eclipse.jetty.websocket.api.WebSocketException;
@@ -22,6 +19,8 @@ import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @WebSocket
 @SuppressWarnings("serial")
 public class ChatMessagesWebSocket extends ApiWebSocket {
@@ -35,6 +34,16 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 	@Override
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		Encoding encoding = getTargetEncoding(session);
+
+		List<String> limitList = queryParams.get("limit");
+		Integer limit = (limitList != null && limitList.size() == 1) ? Integer.parseInt(limitList.get(0)) : null;
+
+		List<String> offsetList = queryParams.get("offset");
+		Integer offset = (offsetList != null && offsetList.size() == 1) ? Integer.parseInt(offsetList.get(0)) : null;
+
+		List<String> reverseList = queryParams.get("offset");
+		Boolean reverse = (reverseList != null && reverseList.size() == 1) ? Boolean.getBoolean(reverseList.get(0)) : null;
 
 		List<String> txGroupIds = queryParams.get("txGroupId");
 		if (txGroupIds != null && txGroupIds.size() == 1) {
@@ -46,7 +55,12 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 						null,
 						txGroupId,
 						null,
-						null, null, null);
+						null,
+						null,
+						null,
+						null,
+						encoding,
+						limit, offset, reverse);
 
 				sendMessages(session, chatMessages);
 			} catch (DataException e) {
@@ -69,11 +83,16 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			List<ChatMessage> chatMessages = repository.getChatRepository().getMessagesMatchingCriteria(
+					null,
+					null,
+					null,
 					null,
 					null,
 					null,
 					involvingAddresses,
-					null, null, null);
+					null,
+					encoding,
+					limit, offset, reverse);
 
 			sendMessages(session, chatMessages);
 		} catch (DataException e) {
@@ -99,7 +118,9 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 
 	@OnWebSocketMessage
 	public void onWebSocketMessage(Session session, String message) {
-		/* ignored */
+		if (Objects.equals(message, "ping")) {
+			session.getRemote().sendStringByFuture("pong");
+		}
 	}
 
 	private void onNotify(Session session, ChatTransactionData chatTransactionData, int txGroupId) {
@@ -147,7 +168,7 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 		// Convert ChatTransactionData to ChatMessage
 		ChatMessage chatMessage;
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			chatMessage = repository.getChatRepository().toChatMessage(chatTransactionData);
+			chatMessage = repository.getChatRepository().toChatMessage(chatTransactionData, getTargetEncoding(session));
 		} catch (DataException e) {
 			// No output this time?
 			return;
@@ -156,4 +177,12 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 		sendMessages(session, Collections.singletonList(chatMessage));
 	}
 
+	private Encoding getTargetEncoding(Session session) {
+		// Default to Base58 if not specified, for backwards support
+		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		List<String> encodingList = queryParams.get("encoding");
+		String encoding = (encodingList != null && encodingList.size() == 1) ? encodingList.get(0) : "BASE58";
+		return Encoding.valueOf(encoding);
+	}
+
 }

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

@@ -24,6 +24,7 @@ import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
 import org.qortal.api.model.CrossChainOfferSummary;
 import org.qortal.controller.Controller;
 import org.qortal.controller.Synchronizer;
+import org.qortal.controller.tradebot.TradeBot;
 import org.qortal.crosschain.SupportedBlockchain;
 import org.qortal.crosschain.ACCT;
 import org.qortal.crosschain.AcctMode;
@@ -173,6 +174,7 @@ 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 +191,23 @@ 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());
+				}
 			}
 		}
 
@@ -311,7 +316,7 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 					throw new DataException("Couldn't fetch historic trades from repository");
 
 				for (ATStateData historicAtState : historicAtStates) {
-					CrossChainOfferSummary historicOfferSummary = produceSummary(repository, acct, historicAtState, null);
+					CrossChainOfferSummary historicOfferSummary = produceSummary(repository, acct, historicAtState, null, null);
 
 					if (!isHistoric.test(historicOfferSummary))
 						continue;
@@ -326,8 +331,10 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 		}
 	}
 
-	private static CrossChainOfferSummary produceSummary(Repository repository, ACCT acct, ATStateData atState, Long timestamp) throws DataException {
-		CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atState);
+	private static CrossChainOfferSummary produceSummary(Repository repository, ACCT acct, ATStateData atState, CrossChainTradeData crossChainTradeData, Long timestamp) throws DataException {
+		if (crossChainTradeData == null) {
+			crossChainTradeData = acct.populateTradeData(repository, atState);
+		}
 
 		long atStateTimestamp;
 
@@ -342,9 +349,16 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 
 	private static List<CrossChainOfferSummary> produceSummaries(Repository repository, ACCT acct, List<ATStateData> atStates, Long timestamp) throws DataException {
 		List<CrossChainOfferSummary> offerSummaries = new ArrayList<>();
+		for (ATStateData atState : atStates) {
+			CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atState);
 
-		for (ATStateData atState : atStates)
-			offerSummaries.add(produceSummary(repository, acct, atState, timestamp));
+			// Ignore trade if it has failed
+			if (TradeBot.getInstance().isFailedTrade(repository, crossChainTradeData)) {
+				continue;
+			}
+
+			offerSummaries.add(produceSummary(repository, acct, atState, crossChainTradeData, timestamp));
+		}
 
 		return offerSummaries;
 	}

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/ArbitraryDataBuildQueueItem.java

@@ -4,6 +4,7 @@ import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.ArbitraryDataFile.*;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.repository.DataException;
+import org.qortal.utils.ArbitraryTransactionUtils;
 import org.qortal.utils.NTP;
 
 import java.io.IOException;
@@ -51,6 +52,9 @@ public class ArbitraryDataBuildQueueItem extends ArbitraryDataResource {
             arbitraryDataReader.loadSynchronously(true);
         } finally {
             this.buildEndTimestamp = NTP.getTime();
+
+            // Update status after build
+            ArbitraryTransactionUtils.getStatus(service, resourceId, identifier, false, true);
         }
     }
 

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

@@ -2,6 +2,7 @@ package org.qortal.arbitrary;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.metadata.ArbitraryDataMetadataCache;
 import org.qortal.arbitrary.misc.Service;
@@ -53,10 +54,6 @@ public class ArbitraryDataBuilder {
     /**
      * Process transactions, but do not build anything
      * This is useful for checking the status of a given resource
-     *
-     * @throws DataException
-     * @throws IOException
-     * @throws MissingDataException
      */
     public void process() throws DataException, IOException, MissingDataException {
         this.fetchTransactions();
@@ -68,10 +65,6 @@ public class ArbitraryDataBuilder {
 
     /**
      * Build the latest state of a given resource
-     *
-     * @throws DataException
-     * @throws IOException
-     * @throws MissingDataException
      */
     public void build() throws DataException, IOException, MissingDataException {
         this.process();
@@ -88,7 +81,7 @@ public class ArbitraryDataBuilder {
             if (latestPut == null) {
                 String message = String.format("Couldn't find PUT transaction for name %s, service %s and identifier %s",
                         this.name, this.service, this.identifierString());
-                throw new DataException(message);
+                throw new DataNotPublishedException(message);
             }
             this.latestPutTransaction = latestPut;
 

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

@@ -4,6 +4,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.crypto.Crypto;
+import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.repository.DataException;
 import org.qortal.settings.Settings;
 import org.qortal.utils.Base58;
@@ -15,7 +16,6 @@ import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.nio.file.StandardCopyOption;
 import java.util.*;
-import java.util.stream.Stream;
 
 import static java.util.Arrays.stream;
 import static java.util.stream.Collectors.toMap;
@@ -79,17 +79,31 @@ public class ArbitraryDataFile {
         this.signature = signature;
     }
 
-    public ArbitraryDataFile(byte[] fileContent, byte[] signature) throws DataException {
+    public ArbitraryDataFile(byte[] fileContent, byte[] signature, boolean useTemporaryFile) throws DataException {
         if (fileContent == null) {
             LOGGER.error("fileContent is null");
             return;
         }
 
+        this.chunks = new ArrayList<>();
         this.hash58 = Base58.encode(Crypto.digest(fileContent));
         this.signature = signature;
         LOGGER.trace(String.format("File digest: %s, size: %d bytes", this.hash58, fileContent.length));
 
-        Path outputFilePath = getOutputFilePath(this.hash58, signature, true);
+        Path outputFilePath;
+        if (useTemporaryFile) {
+            try {
+                outputFilePath = Files.createTempFile("qortalRawData", null);
+                outputFilePath.toFile().deleteOnExit();
+            }
+            catch (IOException e) {
+                throw new DataException(String.format("Unable to write data with hash %s to temporary file: %s", this.hash58, e.getMessage()));
+            }
+        }
+        else {
+            outputFilePath = getOutputFilePath(this.hash58, signature, true);
+        }
+
         File outputFile = outputFilePath.toFile();
         try (FileOutputStream outputStream = new FileOutputStream(outputFile)) {
             outputStream.write(fileContent);
@@ -111,6 +125,41 @@ public class ArbitraryDataFile {
         return ArbitraryDataFile.fromHash58(Base58.encode(hash), signature);
     }
 
+    public static ArbitraryDataFile fromRawData(byte[] data, byte[] signature) throws DataException {
+        if (data == null) {
+            return null;
+        }
+        return new ArbitraryDataFile(data, signature, true);
+    }
+
+    public static ArbitraryDataFile fromTransactionData(ArbitraryTransactionData transactionData) throws DataException {
+        ArbitraryDataFile arbitraryDataFile = null;
+        byte[] signature = transactionData.getSignature();
+        byte[] data = transactionData.getData();
+
+        if (data == null) {
+            return null;
+        }
+
+        // Create data file
+        switch (transactionData.getDataType()) {
+            case DATA_HASH:
+                arbitraryDataFile = ArbitraryDataFile.fromHash(data, signature);
+                break;
+
+            case RAW_DATA:
+                arbitraryDataFile = ArbitraryDataFile.fromRawData(data, signature);
+                break;
+        }
+
+        // Set metadata hash
+        if (arbitraryDataFile != null) {
+            arbitraryDataFile.setMetadataHash(transactionData.getMetadataHash());
+        }
+
+        return arbitraryDataFile;
+    }
+
     public static ArbitraryDataFile fromPath(Path path, byte[] signature) {
         if (path == null) {
             return null;
@@ -260,6 +309,11 @@ public class ArbitraryDataFile {
             this.chunks = new ArrayList<>();
 
             if (file != null) {
+                if (file.exists() && file.length() <= chunkSize) {
+                    // No need to split into chunks if we're already below the chunk size
+                    return 0;
+                }
+
                 try (FileInputStream fileInputStream = new FileInputStream(file);
                      BufferedInputStream bis = new BufferedInputStream(fileInputStream)) {
 
@@ -388,12 +442,15 @@ public class ArbitraryDataFile {
         return false;
     }
 
-    public boolean deleteAll() {
+    public boolean deleteAll(boolean deleteMetadata) {
         // Delete the complete file
         boolean fileDeleted = this.delete();
 
-        // Delete the metadata file
-        boolean metadataDeleted = this.deleteMetadata();
+        // Delete the metadata file if requested
+        boolean metadataDeleted = false;
+        if (deleteMetadata) {
+            metadataDeleted = this.deleteMetadata();
+        }
 
         // Delete the individual chunks
         boolean chunksDeleted = this.deleteAllChunks();
@@ -612,6 +669,22 @@ public class ArbitraryDataFile {
         return this.chunks.size();
     }
 
+    public int fileCount() {
+        int fileCount = this.chunkCount();
+        
+        if (fileCount == 0) {
+            // Transactions without any chunks can already be treated as a complete file
+            fileCount++;
+        }
+
+        if (this.getMetadataHash() != null) {
+            // Add the metadata file
+            fileCount++;
+        }
+
+        return fileCount;
+    }
+
     public List<ArbitraryDataFileChunk> getChunks() {
         return this.chunks;
     }

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

@@ -18,7 +18,7 @@ public class ArbitraryDataFileChunk extends ArbitraryDataFile {
     }
 
     public ArbitraryDataFileChunk(byte[] fileContent, byte[] signature) throws DataException {
-        super(fileContent, signature);
+        super(fileContent, signature, false);
     }
 
     public static ArbitraryDataFileChunk fromHash58(String hash58, byte[] signature) throws DataException {

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

@@ -4,11 +4,11 @@ import org.apache.commons.io.FileUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
 import org.qortal.controller.arbitrary.ArbitraryDataManager;
-import org.qortal.controller.arbitrary.ArbitraryDataStorageManager;
 import org.qortal.crypto.AES;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.ArbitraryTransactionData.*;
@@ -18,10 +18,7 @@ import org.qortal.repository.RepositoryManager;
 import org.qortal.arbitrary.ArbitraryDataFile.*;
 import org.qortal.settings.Settings;
 import org.qortal.transform.Transformer;
-import org.qortal.utils.ArbitraryTransactionUtils;
-import org.qortal.utils.Base58;
-import org.qortal.utils.FilesystemUtils;
-import org.qortal.utils.ZipUtils;
+import org.qortal.utils.*;
 
 import javax.crypto.BadPaddingException;
 import javax.crypto.IllegalBlockSizeException;
@@ -37,6 +34,9 @@ import java.security.InvalidAlgorithmParameterException;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
 
 public class ArbitraryDataReader {
 
@@ -59,7 +59,14 @@ public class ArbitraryDataReader {
     private int layerCount;
     private byte[] latestSignature;
 
-    public ArbitraryDataReader(String resourceId, ResourceIdType resourceIdType, Service service, String identifier) {
+    // The resource being read
+    ArbitraryDataResource arbitraryDataResource = null;
+
+    // Track resources that are currently being loaded, to avoid duplicate concurrent builds
+    // TODO: all builds could be handled by the build queue (even synchronous ones), to avoid the need for this
+    private static Map<String, Long> inProgress = Collections.synchronizedMap(new HashMap<>());
+
+    public ArbitraryDataReader(String resourceId, ResourceIdType resourceIdType, Service service, String identifier) throws DataException {
         // Ensure names are always lowercase
         if (resourceIdType == ResourceIdType.NAME) {
             resourceId = resourceId.toLowerCase();
@@ -83,11 +90,16 @@ public class ArbitraryDataReader {
         this.canRequestMissingFiles = true;
     }
 
-    private Path buildWorkingPath() {
+    private Path buildWorkingPath() throws DataException {
         // Use the user-specified temp dir, as it is deterministic, and is more likely to be located on reusable storage hardware
         String baseDir = Settings.getInstance().getTempDataPath();
         String identifier = this.identifier != null ?  this.identifier : "default";
-        return Paths.get(baseDir, "reader", this.resourceIdType.toString(), this.resourceId, this.service.toString(), identifier);
+
+        try {
+            return Paths.get(baseDir, "reader", this.resourceIdType.toString(), StringUtils.sanitizeString(this.resourceId), this.service.toString(), StringUtils.sanitizeString(identifier));
+        } catch (InvalidPathException e) {
+            throw new DataException(String.format("Invalid path: %s", e.getMessage()));
+        }
     }
 
     public boolean isCachedDataAvailable() {
@@ -115,6 +127,11 @@ public class ArbitraryDataReader {
         return new ArbitraryDataBuildQueueItem(this.resourceId, this.resourceIdType, this.service, this.identifier);
     }
 
+    private ArbitraryDataResource createArbitraryDataResource() {
+        return new ArbitraryDataResource(this.resourceId, this.resourceIdType, this.service, this.identifier);
+    }
+
+
     /**
      * loadAsynchronously
      *
@@ -148,9 +165,6 @@ public class ArbitraryDataReader {
      * If no exception is thrown, you can then use getFilePath() to access the data immediately after returning
      *
      * @param overwrite - set to true to force rebuild an existing cache
-     * @throws IOException
-     * @throws DataException
-     * @throws MissingDataException
      */
     public void loadSynchronously(boolean overwrite) throws DataException, IOException, MissingDataException {
         try {
@@ -162,6 +176,14 @@ public class ArbitraryDataReader {
                 return;
             }
 
+            this.arbitraryDataResource = this.createArbitraryDataResource();
+
+            // Don't allow duplicate loads
+            if (!this.canStartLoading()) {
+                LOGGER.debug("Skipping duplicate load of {}", this.arbitraryDataResource);
+                return;
+            }
+
             this.preExecute();
             this.deleteExistingFiles();
             this.fetch();
@@ -169,9 +191,18 @@ public class ArbitraryDataReader {
             this.uncompress();
             this.validate();
 
-        } catch (DataException e) {
+        } catch (DataNotPublishedException e) {
+            if (e.getMessage() != null) {
+                // Log the message only, to avoid spamming the logs with a full stack trace
+                LOGGER.debug("DataNotPublishedException when trying to load QDN resource: {}", e.getMessage());
+            }
             this.deleteWorkingDirectory();
-            throw new DataException(e.getMessage());
+            throw e;
+
+        } catch (DataException e) {
+            LOGGER.info("DataException when trying to load QDN resource", e);
+            this.deleteWorkingDirectory();
+            throw e;
 
         } finally {
             this.postExecute();
@@ -180,6 +211,7 @@ public class ArbitraryDataReader {
 
     private void preExecute() throws DataException {
         ArbitraryDataBuildManager.getInstance().setBuildInProgress(true);
+
         this.checkEnabled();
         this.createWorkingDirectory();
         this.createUncompressedDirectory();
@@ -187,6 +219,9 @@ public class ArbitraryDataReader {
 
     private void postExecute() {
         ArbitraryDataBuildManager.getInstance().setBuildInProgress(false);
+
+        this.arbitraryDataResource = this.createArbitraryDataResource();
+        ArbitraryDataReader.inProgress.remove(this.arbitraryDataResource.getUniqueKey());
     }
 
     private void checkEnabled() throws DataException {
@@ -195,21 +230,36 @@ public class ArbitraryDataReader {
         }
     }
 
+    private boolean canStartLoading() {
+        // Avoid duplicate builds if we're already loading this resource
+        String uniqueKey = this.arbitraryDataResource.getUniqueKey();
+        if (ArbitraryDataReader.inProgress.containsKey(uniqueKey)) {
+            return false;
+        }
+        ArbitraryDataReader.inProgress.put(uniqueKey, NTP.getTime());
+
+        return true;
+    }
+
     private void createWorkingDirectory() throws DataException {
         try {
             Files.createDirectories(this.workingPath);
         } catch (IOException e) {
-            throw new DataException("Unable to create temp directory");
+            throw new DataException(String.format("Unable to create temp directory %s: %s", this.workingPath, e.getMessage()));
         }
     }
 
     /**
      * Working directory should only be deleted on failure, since it is currently used to
      * 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 {
@@ -281,7 +331,7 @@ public class ArbitraryDataReader {
                 break;
 
             default:
-                throw new DataException(String.format("Unknown resource ID type specified: %s", resourceIdType.toString()));
+                throw new DataException(String.format("Unknown resource ID type specified: %s", resourceIdType));
         }
     }
 
@@ -337,11 +387,6 @@ public class ArbitraryDataReader {
             throw new DataException(String.format("Transaction data not found for signature %s", this.resourceId));
         }
 
-        // Load hashes
-        byte[] digest = transactionData.getData();
-        byte[] metadataHash = transactionData.getMetadataHash();
-        byte[] signature = transactionData.getSignature();
-
         // Load secret
         byte[] secret = transactionData.getSecret();
         if (secret != null) {
@@ -349,16 +394,17 @@ public class ArbitraryDataReader {
         }
 
         // Load data file(s)
-        ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromHash(digest, signature);
+        ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromTransactionData(transactionData);
         ArbitraryTransactionUtils.checkAndRelocateMiscFiles(transactionData);
-        arbitraryDataFile.setMetadataHash(metadataHash);
+        if (arbitraryDataFile == null) {
+            throw new DataException(String.format("arbitraryDataFile is null"));
+        }
 
         if (!arbitraryDataFile.allFilesExist()) {
-            if (ArbitraryDataStorageManager.getInstance().isNameBlocked(transactionData.getName())) {
+            if (ListUtils.isNameBlocked(transactionData.getName())) {
                 throw new DataException(
                         String.format("Unable to request missing data for file %s because the name is blocked", arbitraryDataFile));
-            }
-            else {
+            } else {
                 // Ask the arbitrary data manager to fetch data for this transaction
                 String message;
                 if (this.canRequestMissingFiles) {
@@ -369,8 +415,7 @@ public class ArbitraryDataReader {
                     } else {
                         message = String.format("Unable to reissue request for missing file %s for signature %s due to rate limit. Please try again later.", arbitraryDataFile, Base58.encode(transactionData.getSignature()));
                     }
-                }
-                else {
+                } else {
                     message = String.format("Missing data for file %s", arbitraryDataFile);
                 }
 
@@ -380,21 +425,25 @@ public class ArbitraryDataReader {
             }
         }
 
-        if (arbitraryDataFile.allChunksExist() && !arbitraryDataFile.exists()) {
-            // We have all the chunks but not the complete file, so join them
-            arbitraryDataFile.join();
+        // Data hashes need some extra processing
+        if (transactionData.getDataType() == DataType.DATA_HASH) {
+            if (arbitraryDataFile.allChunksExist() && !arbitraryDataFile.exists()) {
+                // We have all the chunks but not the complete file, so join them
+                arbitraryDataFile.join();
+            }
+
+            // If the complete file still doesn't exist then something went wrong
+            if (!arbitraryDataFile.exists()) {
+                throw new IOException(String.format("File doesn't exist: %s", arbitraryDataFile));
+            }
+            // Ensure the complete hash matches the joined chunks
+            if (!Arrays.equals(arbitraryDataFile.digest(), transactionData.getData())) {
+                // Delete the invalid file
+                arbitraryDataFile.delete();
+                throw new DataException("Unable to validate complete file hash");
+            }
         }
 
-        // If the complete file still doesn't exist then something went wrong
-        if (!arbitraryDataFile.exists()) {
-            throw new IOException(String.format("File doesn't exist: %s", arbitraryDataFile));
-        }
-        // Ensure the complete hash matches the joined chunks
-        if (!Arrays.equals(arbitraryDataFile.digest(), digest)) {
-            // Delete the invalid file
-            arbitraryDataFile.delete();
-            throw new DataException("Unable to validate complete file hash");
-        }
         // Ensure the file's size matches the size reported by the transaction (throws a DataException if not)
         arbitraryDataFile.validateFileSize(transactionData.getSize());
 
@@ -408,6 +457,7 @@ 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");
 
@@ -420,9 +470,11 @@ public class ArbitraryDataReader {
         byte[] secret = this.secret58 != null ? Base58.decode(this.secret58) : null;
         if (secret != null && secret.length == Transformer.AES256_LENGTH) {
             try {
+                LOGGER.debug("Decrypting {} using algorithm {}...", this.arbitraryDataResource, 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());
+                LOGGER.debug("Finished decrypting {} using algorithm {}", this.arbitraryDataResource, algorithm);
 
                 // Replace filePath pointer with the encrypted file path
                 // Don't delete the original ArbitraryDataFile, as this is handled in the cleanup phase
@@ -430,7 +482,8 @@ 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 %s using algorithm %s", this.arbitraryDataResource, 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
@@ -456,7 +509,9 @@ public class ArbitraryDataReader {
 
             // Handle each type of compression
             if (compression == Compression.ZIP) {
+                LOGGER.debug("Unzipping {}...", this.arbitraryDataResource);
                 ZipUtils.unzip(this.filePath.toString(), this.uncompressedPath.getParent().toString());
+                LOGGER.debug("Finished unzipping {}", this.arbitraryDataResource);
             }
             else if (compression == Compression.NONE) {
                 Files.createDirectories(this.uncompressedPath);
@@ -477,7 +532,12 @@ 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);
+                }
             }
         }
 
@@ -487,10 +547,12 @@ public class ArbitraryDataReader {
 
     private void validate() throws IOException, DataException {
         if (this.service.isValidationRequired()) {
+            LOGGER.debug("Validating {}...", this.arbitraryDataResource);
             Service.ValidationResult result = this.service.validate(this.filePath);
             if (result != Service.ValidationResult.OK) {
                 throw new DataException(String.format("Validation of %s failed: %s", this.service, result.toString()));
             }
+            LOGGER.debug("Finished validating {}", this.arbitraryDataResource);
         }
     }
 

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

@@ -2,6 +2,7 @@ package org.qortal.arbitrary;
 
 import com.google.common.io.Resources;
 import org.apache.commons.io.FileUtils;
+import org.apache.commons.lang3.ArrayUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.api.HTMLParser;
@@ -34,36 +35,40 @@ public class ArbitraryDataRenderer {
     private final String resourceId;
     private final ResourceIdType resourceIdType;
     private final Service service;
+    private final String identifier;
     private String theme = "light";
     private String inPath;
     private final String secret58;
     private final String prefix;
-    private final boolean usePrefix;
+    private final boolean includeResourceIdInPrefix;
     private final boolean async;
+    private final String qdnContext;
     private final HttpServletRequest request;
     private final HttpServletResponse response;
     private final ServletContext context;
 
-    public ArbitraryDataRenderer(String resourceId, ResourceIdType resourceIdType, Service service, String inPath,
-                                 String secret58, String prefix, boolean usePrefix, boolean async,
+    public ArbitraryDataRenderer(String resourceId, ResourceIdType resourceIdType, Service service, String identifier,
+                                 String inPath, String secret58, String prefix, boolean includeResourceIdInPrefix, boolean async, String qdnContext,
                                  HttpServletRequest request, HttpServletResponse response, ServletContext context) {
 
         this.resourceId = resourceId;
         this.resourceIdType = resourceIdType;
         this.service = service;
+        this.identifier = identifier != null ? identifier : "default";
         this.inPath = inPath;
         this.secret58 = secret58;
         this.prefix = prefix;
-        this.usePrefix = usePrefix;
+        this.includeResourceIdInPrefix = includeResourceIdInPrefix;
         this.async = async;
+        this.qdnContext = qdnContext;
         this.request = request;
         this.response = response;
         this.context = context;
     }
 
     public HttpServletResponse render() {
-        if (!inPath.startsWith(File.separator)) {
-            inPath = File.separator + inPath;
+        if (!inPath.startsWith("/")) {
+            inPath = "/" + inPath;
         }
 
         // Don't render data if QDN is disabled
@@ -71,14 +76,16 @@ public class ArbitraryDataRenderer {
             return ArbitraryDataRenderer.getResponse(response, 500, "QDN is disabled in settings");
         }
 
-        ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(resourceId, resourceIdType, service, null);
-        arbitraryDataReader.setSecret58(secret58); // Optional, used for loading encrypted file hashes only
+        ArbitraryDataReader arbitraryDataReader;
         try {
+            arbitraryDataReader = new ArbitraryDataReader(resourceId, resourceIdType, service, identifier);
+            arbitraryDataReader.setSecret58(secret58); // Optional, used for loading encrypted file hashes only
+
             if (!arbitraryDataReader.isCachedDataAvailable()) {
                 // If async is requested, show a loading screen whilst build is in progress
                 if (async) {
                     arbitraryDataReader.loadAsynchronously(false, 10);
-                    return this.getLoadingResponse(service, resourceId, theme);
+                    return this.getLoadingResponse(service, resourceId, identifier, theme);
                 }
 
                 // Otherwise, loop until we have data
@@ -111,23 +118,59 @@ public class ArbitraryDataRenderer {
         }
         String unzippedPath = path.toString();
 
+        // Set path automatically for single file resources (except for apps, which handle routing differently)
+        String[] files = ArrayUtils.removeElement(new File(unzippedPath).list(), ".qortal");
+        if (files.length == 1 && this.service != Service.APP) {
+            // This is a single file resource
+            inPath = files[0];
+        }
+
         try {
             String filename = this.getFilename(unzippedPath, inPath);
-            String filePath = Paths.get(unzippedPath, filename).toString();
+            Path filePath = Paths.get(unzippedPath, filename);
+            boolean usingCustomRouting = false;
+            
+            // If the file doesn't exist, we may need to route the request elsewhere, or cleanup
+            if (!Files.exists(filePath)) {
+                if (inPath.equals("/")) {
+                    // Delete the unzipped folder if no index file was found
+                    try {
+                        FileUtils.deleteDirectory(new File(unzippedPath));
+                    } catch (IOException e) {
+                        LOGGER.debug("Unable to delete directory: {}", unzippedPath, e);
+                    }
+                }
+
+                // If this is an app, then forward all unhandled requests to the index, to give the app the option to route it
+                if (this.service == Service.APP) {
+                    // Locate index file
+                    List<String> indexFiles = ArbitraryDataRenderer.indexFiles();
+                    for (String indexFile : indexFiles) {
+                        Path indexPath = Paths.get(unzippedPath, indexFile);
+                        if (Files.exists(indexPath)) {
+                            // Forward request to index file
+                            filePath = indexPath;
+                            filename = indexFile;
+                            usingCustomRouting = true;
+                            break;
+                        }
+                    }
+                }
+            }
 
             if (HTMLParser.isHtmlFile(filename)) {
                 // HTML file - needs to be parsed
-                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);
+                byte[] data = Files.readAllBytes(filePath); // TODO: limit file size that can be read into memory
+                HTMLParser htmlParser = new HTMLParser(resourceId, inPath, prefix, includeResourceIdInPrefix, data, qdnContext, service, identifier, theme, usingCustomRouting);
                 htmlParser.addAdditionalHeaderTags();
-                response.addHeader("Content-Security-Policy", "default-src 'self' 'unsafe-inline' 'unsafe-eval'; media-src 'self' blob:; img-src 'self' data: blob:;");
+                response.addHeader("Content-Security-Policy", "default-src 'self' 'unsafe-inline' 'unsafe-eval'; media-src 'self' data: blob:; img-src 'self' data: blob:;");
                 response.setContentType(context.getMimeType(filename));
                 response.setContentLength(htmlParser.getData().length);
                 response.getOutputStream().write(htmlParser.getData());
             }
             else {
                 // Regular file - can be streamed directly
-                File file = new File(filePath);
+                File file = filePath.toFile();
                 FileInputStream inputStream = new FileInputStream(file);
                 response.addHeader("Content-Security-Policy", "default-src 'self'");
                 response.setContentType(context.getMimeType(filename));
@@ -143,14 +186,6 @@ public class ArbitraryDataRenderer {
             return response;
         } catch (FileNotFoundException | NoSuchFileException e) {
             LOGGER.info("Unable to serve file: {}", e.getMessage());
-            if (inPath.equals("/")) {
-                // Delete the unzipped folder if no index file was found
-                try {
-                    FileUtils.deleteDirectory(new File(unzippedPath));
-                } catch (IOException ioException) {
-                    LOGGER.debug("Unable to delete directory: {}", unzippedPath, e);
-                }
-            }
         } catch (IOException e) {
             LOGGER.info("Unable to serve file at path {}: {}", inPath, e.getMessage());
         }
@@ -172,7 +207,7 @@ public class ArbitraryDataRenderer {
         return userPath;
     }
 
-    private HttpServletResponse getLoadingResponse(Service service, String name, String theme) {
+    private HttpServletResponse getLoadingResponse(Service service, String name, String identifier, String theme) {
         String responseString = "";
         URL url = Resources.getResource("loading/index.html");
         try {
@@ -181,6 +216,7 @@ public class ArbitraryDataRenderer {
             // Replace vars
             responseString = responseString.replace("%%SERVICE%%", service.toString());
             responseString = responseString.replace("%%NAME%%", name);
+            responseString = responseString.replace("%%IDENTIFIER%%", identifier);
             responseString = responseString.replace("%%THEME%%", theme);
 
         } catch (IOException e) {

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

@@ -3,20 +3,22 @@ package org.qortal.arbitrary;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.ArbitraryDataFile.ResourceIdType;
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
 import org.qortal.controller.arbitrary.ArbitraryDataManager;
 import org.qortal.controller.arbitrary.ArbitraryDataStorageManager;
+import org.qortal.data.arbitrary.ArbitraryResourceData;
 import org.qortal.data.arbitrary.ArbitraryResourceStatus;
 import org.qortal.data.transaction.ArbitraryTransactionData;
-import org.qortal.list.ResourceListManager;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 import org.qortal.settings.Settings;
 import org.qortal.utils.ArbitraryTransactionUtils;
 import org.qortal.utils.FilesystemUtils;
+import org.qortal.utils.ListUtils;
 import org.qortal.utils.NTP;
 
 import java.io.IOException;
@@ -42,6 +44,7 @@ public class ArbitraryDataResource {
     private int layerCount;
     private Integer localChunkCount = null;
     private Integer totalChunkCount = null;
+    private boolean exists = false;
 
     public ArbitraryDataResource(String resourceId, ResourceIdType resourceIdType, Service service, String identifier) {
         this.resourceId = resourceId.toLowerCase();
@@ -55,11 +58,39 @@ public class ArbitraryDataResource {
         this.identifier = identifier;
     }
 
-    public ArbitraryResourceStatus getStatus(boolean quick) {
+    public ArbitraryResourceStatus getStatusAndUpdateCache(boolean updateCache) {
+        ArbitraryResourceStatus arbitraryResourceStatus = null;
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            arbitraryResourceStatus = this.getStatus(repository);
+
+            if (updateCache) {
+                // Update cache if possible
+                ArbitraryResourceStatus.Status status = arbitraryResourceStatus != null ? arbitraryResourceStatus.getStatus() : null;
+                ArbitraryResourceData arbitraryResourceData = new ArbitraryResourceData(this.service, this.resourceId, this.identifier);
+                repository.discardChanges();
+                repository.getArbitraryRepository().setStatus(arbitraryResourceData, status);
+                repository.saveChanges();
+            }
+        } catch (DataException e) {
+            LOGGER.info("Unable to update status cache for resource {}: {}", this.toString(), e.getMessage());
+        }
+
+        return arbitraryResourceStatus;
+    }
+
+    /**
+     * Get current status of resource
+     *
+     * @param repository
+     * @return the resource's status
+     */
+    public ArbitraryResourceStatus getStatus(Repository repository) {
         // Calculate the chunk counts
-        // Avoid this for "quick" statuses, to speed things up
-        if (!quick) {
-            this.calculateChunkCounts();
+        this.calculateChunkCounts(repository);
+
+        if (!this.exists) {
+            return new ArbitraryResourceStatus(Status.NOT_PUBLISHED, this.localChunkCount, this.totalChunkCount);
         }
 
         if (resourceIdType != ResourceIdType.NAME) {
@@ -68,8 +99,7 @@ public class ArbitraryDataResource {
         }
 
         // Check if the name is blocked
-        if (ResourceListManager.getInstance()
-                .listContains("blockedNames", this.resourceId, false)) {
+        if (ListUtils.isNameBlocked(this.resourceId)) {
             return new ArbitraryResourceStatus(Status.BLOCKED, this.localChunkCount, this.totalChunkCount);
         }
 
@@ -81,18 +111,23 @@ public class ArbitraryDataResource {
         }
 
         // Firstly check the cache to see if it's already built
-        ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(
-                resourceId, resourceIdType, service, identifier);
-        if (arbitraryDataReader.isCachedDataAvailable()) {
-            return new ArbitraryResourceStatus(Status.READY, this.localChunkCount, this.totalChunkCount);
+        try {
+            ArbitraryDataReader arbitraryDataReader = new ArbitraryDataReader(
+                    resourceId, resourceIdType, service, identifier);
+            if (arbitraryDataReader.isCachedDataAvailable()) {
+                return new ArbitraryResourceStatus(Status.READY, this.localChunkCount, this.totalChunkCount);
+            }
+        } catch (DataException e) {
+            // Assume no usable data
+            return new ArbitraryResourceStatus(Status.PUBLISHED, this.localChunkCount, this.totalChunkCount);
         }
 
         // Check if we have all data locally for this resource
-        if (!this.allFilesDownloaded()) {
-            if (this.isDownloading()) {
+        if (!this.allFilesDownloaded(repository)) {
+            if (this.isDownloading(repository)) {
                 return new ArbitraryResourceStatus(Status.DOWNLOADING, this.localChunkCount, this.totalChunkCount);
             }
-            else if (this.isDataPotentiallyAvailable()) {
+            else if (this.isDataPotentiallyAvailable(repository)) {
                 return new ArbitraryResourceStatus(Status.PUBLISHED, this.localChunkCount, this.totalChunkCount);
             }
             return new ArbitraryResourceStatus(Status.MISSING_DATA, this.localChunkCount, this.totalChunkCount);
@@ -134,21 +169,23 @@ public class ArbitraryDataResource {
         return null;
     }
 
-    public boolean delete() {
+    public boolean delete(Repository repository, boolean deleteMetadata) {
         try {
-            this.fetchTransactions();
+            this.fetchTransactions(repository);
+            if (this.transactions == null) {
+                return false;
+            }
 
             List<ArbitraryTransactionData> transactionDataList = new ArrayList<>(this.transactions);
 
             for (ArbitraryTransactionData transactionData : transactionDataList) {
-                byte[] hash = transactionData.getData();
-                byte[] metadataHash = transactionData.getMetadataHash();
-                byte[] signature = transactionData.getSignature();
-                ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromHash(hash, signature);
-                arbitraryDataFile.setMetadataHash(metadataHash);
+                ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromTransactionData(transactionData);
+                if (arbitraryDataFile == null) {
+                    continue;
+                }
 
                 // Delete any chunks or complete files from each transaction
-                arbitraryDataFile.deleteAll();
+                arbitraryDataFile.deleteAll(deleteMetadata);
             }
 
             // Also delete cached data for the entire resource
@@ -183,7 +220,7 @@ public class ArbitraryDataResource {
         }
     }
 
-    private boolean allFilesDownloaded() {
+    private boolean allFilesDownloaded(Repository repository) {
         // Use chunk counts to speed things up if we can
         if (this.localChunkCount != null && this.totalChunkCount != null &&
                 this.localChunkCount >= this.totalChunkCount) {
@@ -191,7 +228,10 @@ public class ArbitraryDataResource {
         }
 
         try {
-            this.fetchTransactions();
+            this.fetchTransactions(repository);
+            if (this.transactions == null) {
+                return false;
+            }
 
             List<ArbitraryTransactionData> transactionDataList = new ArrayList<>(this.transactions);
 
@@ -208,9 +248,22 @@ public class ArbitraryDataResource {
         }
     }
 
-    private void calculateChunkCounts() {
+    /**
+     * Calculate chunk counts of a resource
+     *
+     * @param repository optional - a new instance will be created if null
+     */
+    private void calculateChunkCounts(Repository repository) {
         try {
-            this.fetchTransactions();
+            this.fetchTransactions(repository);
+            if (this.transactions == null) {
+                this.exists = false;
+                this.localChunkCount = 0;
+                this.totalChunkCount = 0;
+                return;
+            }
+
+            this.exists = true;
 
             List<ArbitraryTransactionData> transactionDataList = new ArrayList<>(this.transactions);
             int localChunkCount = 0;
@@ -227,9 +280,12 @@ public class ArbitraryDataResource {
         } catch (DataException e) {}
     }
 
-    private boolean isRateLimited() {
+    private boolean isRateLimited(Repository repository) {
         try {
-            this.fetchTransactions();
+            this.fetchTransactions(repository);
+            if (this.transactions == null) {
+                return true;
+            }
 
             List<ArbitraryTransactionData> transactionDataList = new ArrayList<>(this.transactions);
 
@@ -250,9 +306,13 @@ public class ArbitraryDataResource {
      * This is only used to give an indication to the user of progress
      * @return - whether data might be available on the network
      */
-    private boolean isDataPotentiallyAvailable() {
+    private boolean isDataPotentiallyAvailable(Repository repository) {
         try {
-            this.fetchTransactions();
+            this.fetchTransactions(repository);
+            if (this.transactions == null) {
+                return false;
+            }
+
             Long now = NTP.getTime();
             if (now == null) {
                 return false;
@@ -281,9 +341,13 @@ public class ArbitraryDataResource {
      * This is only used to give an indication to the user of progress
      * @return - whether we are trying to download the resource
      */
-    private boolean isDownloading() {
+    private boolean isDownloading(Repository repository) {
         try {
-            this.fetchTransactions();
+            this.fetchTransactions(repository);
+            if (this.transactions == null) {
+                return false;
+            }
+
             Long now = NTP.getTime();
             if (now == null) {
                 return false;
@@ -310,22 +374,26 @@ public class ArbitraryDataResource {
     }
 
 
-
-    private void fetchTransactions() throws DataException {
+    /**
+     * Fetch relevant arbitrary transactions for resource
+     *
+     * @param repository
+     * @throws DataException
+     */
+    private void fetchTransactions(Repository repository) throws DataException {
         if (this.transactions != null && !this.transactions.isEmpty()) {
             // Already fetched
             return;
         }
 
-        try (final Repository repository = RepositoryManager.getRepository()) {
-
+        try {
             // Get the most recent PUT
             ArbitraryTransactionData latestPut = repository.getArbitraryRepository()
                     .getLatestTransaction(this.resourceId, this.service, ArbitraryTransactionData.Method.PUT, this.identifier);
             if (latestPut == null) {
                 String message = String.format("Couldn't find PUT transaction for name %s, service %s and identifier %s",
                         this.resourceId, this.service, this.identifierString());
-                throw new DataException(message);
+                throw new DataNotPublishedException(message);
             }
             this.latestPutTransaction = latestPut;
 
@@ -336,7 +404,10 @@ public class ArbitraryDataResource {
             this.transactions = transactionDataList;
             this.layerCount = transactionDataList.size();
 
-        } catch (DataException e) {
+        } catch (DataNotPublishedException e) {
+            // Ignore without logging
+        }
+        catch (DataException e) {
             LOGGER.info(String.format("Repository error when fetching transactions for resource %s: %s", this, e.getMessage()));
         }
     }

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

@@ -9,6 +9,7 @@ import org.qortal.arbitrary.metadata.ArbitraryDataMetadataPatch;
 import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Category;
 import org.qortal.arbitrary.misc.Service;
+import org.qortal.crypto.AES;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.PaymentData;
 import org.qortal.data.transaction.ArbitraryTransactionData;
@@ -46,6 +47,7 @@ public class ArbitraryDataTransactionBuilder {
     private static final double MAX_FILE_DIFF = 0.5f;
 
     private final String publicKey58;
+    private final long fee;
     private final Path path;
     private final String name;
     private Method method;
@@ -64,11 +66,12 @@ public class ArbitraryDataTransactionBuilder {
     private ArbitraryTransactionData arbitraryTransactionData;
     private ArbitraryDataFile arbitraryDataFile;
 
-    public ArbitraryDataTransactionBuilder(Repository repository, String publicKey58, Path path, String name,
+    public ArbitraryDataTransactionBuilder(Repository repository, String publicKey58, long fee, Path path, String name,
                                            Method method, Service service, String identifier,
                                            String title, String description, List<String> tags, Category category) {
         this.repository = repository;
         this.publicKey58 = publicKey58;
+        this.fee = fee;
         this.path = path;
         this.name = name;
         this.method = method;
@@ -114,8 +117,9 @@ public class ArbitraryDataTransactionBuilder {
     }
 
     private Method determineMethodAutomatically() throws DataException {
-        ArbitraryDataReader reader = new ArbitraryDataReader(this.name, ResourceIdType.NAME, this.service, this.identifier);
+        ArbitraryDataReader reader;
         try {
+            reader = new ArbitraryDataReader(this.name, ResourceIdType.NAME, this.service, this.identifier);
             reader.loadSynchronously(true);
         } catch (Exception e) {
             // Catch all exceptions if the existing resource cannot be loaded first time
@@ -179,6 +183,7 @@ public class ArbitraryDataTransactionBuilder {
                 for (ModifiedPath path : metadata.getModifiedPaths()) {
                     if (path.getDiffType() != DiffType.COMPLETE_FILE) {
                         atLeastOnePatch = true;
+                        break;
                     }
                 }
             }
@@ -187,6 +192,14 @@ public class ArbitraryDataTransactionBuilder {
                 return Method.PUT;
             }
 
+            // We can't use PATCH for on-chain data because this requires the .qortal directory, which can't be put on chain
+            final boolean isSingleFileResource = FilesystemUtils.isSingleFileResource(this.path, false);
+            final boolean shouldUseOnChainData = (isSingleFileResource && AES.getEncryptedFileSize(FilesystemUtils.getSingleFileContents(path).length) <= ArbitraryTransaction.MAX_DATA_SIZE);
+            if (shouldUseOnChainData) {
+                LOGGER.info("Data size is small enough to go on chain - using PUT");
+                return Method.PUT;
+            }
+
             // State is appropriate for a PATCH transaction
             return Method.PATCH;
         }
@@ -227,10 +240,12 @@ public class ArbitraryDataTransactionBuilder {
                 random.nextBytes(lastReference);
             }
 
-            Compression compression = Compression.ZIP;
+            // Single file resources are handled differently, especially for very small data payloads, as these go on chain
+            final boolean isSingleFileResource = FilesystemUtils.isSingleFileResource(path, false);
+            final boolean shouldUseOnChainData = (isSingleFileResource && AES.getEncryptedFileSize(FilesystemUtils.getSingleFileContents(path).length) <= ArbitraryTransaction.MAX_DATA_SIZE);
 
-            // FUTURE? Use zip compression for directories, or no compression for single files
-            // Compression compression = (path.toFile().isDirectory()) ? Compression.ZIP : Compression.NONE;
+            // Use zip compression if data isn't going on chain
+            Compression compression = shouldUseOnChainData ? Compression.NONE : Compression.ZIP;
 
             ArbitraryDataWriter arbitraryDataWriter = new ArbitraryDataWriter(path, name, service, identifier, method,
                     compression, title, description, tags, category);
@@ -248,45 +263,52 @@ public class ArbitraryDataTransactionBuilder {
                 throw new DataException("Arbitrary data file is null");
             }
 
-            // Get chunks metadata file
+            // Get metadata file
             ArbitraryDataFile metadataFile = arbitraryDataFile.getMetadataFile();
             if (metadataFile == null && arbitraryDataFile.chunkCount() > 1) {
                 throw new DataException(String.format("Chunks metadata data file is null but there are %d chunks", arbitraryDataFile.chunkCount()));
             }
 
-            String digest58 = arbitraryDataFile.digest58();
-            if (digest58 == null) {
-                LOGGER.error("Unable to calculate file digest");
-                throw new DataException("Unable to calculate file digest");
+            // Default to using a data hash, with data held off-chain
+            ArbitraryTransactionData.DataType dataType = ArbitraryTransactionData.DataType.DATA_HASH;
+            byte[] data = arbitraryDataFile.digest();
+
+            // For small, single-chunk resources, we can store the data directly on chain
+            if (shouldUseOnChainData && arbitraryDataFile.getBytes().length <= ArbitraryTransaction.MAX_DATA_SIZE && arbitraryDataFile.chunkCount() == 0) {
+                // Within allowed on-chain data size
+                dataType = DataType.RAW_DATA;
+                data = arbitraryDataFile.getBytes();
             }
 
             final BaseTransactionData baseTransactionData = new BaseTransactionData(now, Group.NO_GROUP,
-                    lastReference, creatorPublicKey, 0L, null);
+                    lastReference, creatorPublicKey, fee, null);
             final int size = (int) arbitraryDataFile.size();
             final int version = 5;
             final int nonce = 0;
             byte[] secret = arbitraryDataFile.getSecret();
-            final ArbitraryTransactionData.DataType dataType = ArbitraryTransactionData.DataType.DATA_HASH;
-            final byte[] digest = arbitraryDataFile.digest();
+
             final byte[] metadataHash = (metadataFile != null) ? metadataFile.getHash() : null;
             final List<PaymentData> payments = new ArrayList<>();
 
             ArbitraryTransactionData transactionData = new ArbitraryTransactionData(baseTransactionData,
-                    version, service, nonce, size, name, identifier, method,
-                    secret, compression, digest, dataType, metadataHash, payments);
+                    version, service.value, nonce, size, name, identifier, method,
+                    secret, compression, data, dataType, metadataHash, payments);
 
             this.arbitraryTransactionData = transactionData;
 
-        } catch (DataException e) {
+        } catch (DataException | IOException e) {
             if (arbitraryDataFile != null) {
-                arbitraryDataFile.deleteAll();
+                arbitraryDataFile.deleteAll(true);
             }
-            throw(e);
+            throw new DataException(e);
         }
 
     }
 
     private boolean isMetadataEqual(ArbitraryDataTransactionMetadata existingMetadata) {
+        if (existingMetadata == null) {
+            return !this.hasMetadata();
+        }
         if (!Objects.equals(existingMetadata.getTitle(), this.title)) {
             return false;
         }
@@ -302,6 +324,10 @@ public class ArbitraryDataTransactionBuilder {
         return true;
     }
 
+    private boolean hasMetadata() {
+        return (this.title != null || this.description != null || this.category != null || this.tags != null);
+    }
+
     public void computeNonce() throws DataException {
         if (this.arbitraryTransactionData == null) {
             throw new DataException("Arbitrary transaction data is required to compute nonce");
@@ -313,7 +339,7 @@ public class ArbitraryDataTransactionBuilder {
 
         Transaction.ValidationResult result = transaction.isValidUnconfirmed();
         if (result != Transaction.ValidationResult.OK) {
-            arbitraryDataFile.deleteAll();
+            arbitraryDataFile.deleteAll(true);
             throw new DataException(String.format("Arbitrary transaction invalid: %s", result));
         }
         LOGGER.info("Transaction is valid");

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

@@ -1,5 +1,7 @@
 package org.qortal.arbitrary;
 
+import com.j256.simplemagic.ContentInfo;
+import com.j256.simplemagic.ContentInfoUtil;
 import org.apache.commons.io.FileUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -23,16 +25,15 @@ import javax.crypto.NoSuchPaddingException;
 import javax.crypto.SecretKey;
 import java.io.File;
 import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
+import java.net.FileNameMap;
+import java.net.URLConnection;
+import java.nio.file.*;
 import java.security.InvalidAlgorithmParameterException;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Objects;
+import java.util.*;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public class ArbitraryDataWriter {
 
@@ -50,6 +51,8 @@ public class ArbitraryDataWriter {
     private final String description;
     private final List<String> tags;
     private final Category category;
+    private List<String> files;
+    private String mimeType;
 
     private int chunkSize = ArbitraryDataFile.CHUNK_SIZE;
 
@@ -80,12 +83,15 @@ public class ArbitraryDataWriter {
         this.description = ArbitraryDataTransactionMetadata.limitDescription(description);
         this.tags = ArbitraryDataTransactionMetadata.limitTags(tags);
         this.category = category;
+        this.files = new ArrayList<>(); // Populated in buildFileList()
+        this.mimeType = null; // Populated in buildFileList()
     }
 
     public void save() throws IOException, DataException, InterruptedException, MissingDataException {
         try {
             this.preExecute();
             this.validateService();
+            this.buildFileList();
             this.process();
             this.compress();
             this.encrypt();
@@ -101,10 +107,9 @@ public class ArbitraryDataWriter {
     private void preExecute() throws DataException {
         this.checkEnabled();
 
-        // Enforce compression when uploading a directory
-        File file = new File(this.filePath.toString());
-        if (file.isDirectory() && compression == Compression.NONE) {
-            throw new DataException("Unable to upload a directory without compression");
+        // Enforce compression when uploading multiple files
+        if (!FilesystemUtils.isSingleFileResource(this.filePath, false) && compression == Compression.NONE) {
+            throw new DataException("Unable to publish multiple files without compression");
         }
 
         // Create temporary working directory
@@ -143,6 +148,48 @@ public class ArbitraryDataWriter {
         }
     }
 
+    private void buildFileList() throws IOException {
+        // Check if the path already points to a single file
+        boolean isSingleFile = this.filePath.toFile().isFile();
+        Path singleFilePath = null;
+        if (isSingleFile) {
+            this.files.add(this.filePath.getFileName().toString());
+            singleFilePath = this.filePath;
+        }
+        else {
+            // Multi file resources (or a single file in a directory) require a walk through the directory tree
+            try (Stream<Path> stream = Files.walk(this.filePath)) {
+                this.files = stream
+                        .filter(Files::isRegularFile)
+                        .map(p -> this.filePath.relativize(p).toString())
+                        .filter(s -> !s.isEmpty())
+                        .collect(Collectors.toList());
+
+                if (this.files.size() == 1) {
+                    singleFilePath = Paths.get(this.filePath.toString(), this.files.get(0));
+
+                    // Update filePath to point to the single file (instead of the directory containing the file)
+                    this.filePath = singleFilePath;
+                }
+            }
+        }
+
+        if (singleFilePath != null) {
+            // Single file resource, so try and determine the MIME type
+            ContentInfoUtil util = new ContentInfoUtil();
+            ContentInfo info = util.findMatch(singleFilePath.toFile());
+            if (info != null) {
+                // Attempt to extract MIME type from file contents
+                this.mimeType = info.getMimeType();
+            }
+            else {
+                // Fall back to using the filename
+                FileNameMap fileNameMap = URLConnection.getFileNameMap();
+                this.mimeType = fileNameMap.getContentTypeFor(singleFilePath.toFile().getName());
+            }
+        }
+    }
+
     private void process() throws DataException, IOException, MissingDataException {
         switch (this.method) {
 
@@ -269,9 +316,6 @@ public class ArbitraryDataWriter {
         if (chunkCount > 0) {
             LOGGER.info(String.format("Successfully split into %d chunk%s", chunkCount, (chunkCount == 1 ? "" : "s")));
         }
-        else {
-            throw new DataException("Unable to split file into chunks");
-        }
     }
 
     private void createMetadataFile() throws IOException, DataException {
@@ -285,6 +329,8 @@ public class ArbitraryDataWriter {
             metadata.setTags(this.tags);
             metadata.setCategory(this.category);
             metadata.setChunks(this.arbitraryDataFile.chunkHashList());
+            metadata.setFiles(this.files);
+            metadata.setMimeType(this.mimeType);
             metadata.write();
 
             // Create an ArbitraryDataFile from the JSON file (we don't have a signature yet)

src/main/java/org/qortal/arbitrary/exception/DataNotPublishedException.java

@@ -0,0 +1,22 @@
+package org.qortal.arbitrary.exception;
+
+import org.qortal.repository.DataException;
+
+public class DataNotPublishedException extends DataException {
+
+	public DataNotPublishedException() {
+	}
+
+	public DataNotPublishedException(String message) {
+		super(message);
+	}
+
+	public DataNotPublishedException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+	public DataNotPublishedException(Throwable cause) {
+		super(cause);
+	}
+
+}

src/main/java/org/qortal/arbitrary/metadata/ArbitraryDataMetadata.java

@@ -2,12 +2,14 @@ package org.qortal.arbitrary.metadata;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.json.JSONException;
 import org.qortal.repository.DataException;
 
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 
@@ -34,7 +36,7 @@ public class ArbitraryDataMetadata {
         this.filePath = filePath;
     }
 
-    protected void readJson() throws DataException {
+    protected void readJson() throws DataException, JSONException {
         // To be overridden
     }
 
@@ -44,8 +46,13 @@ public class ArbitraryDataMetadata {
 
 
     public void read() throws IOException, DataException {
-        this.loadJson();
-        this.readJson();
+        try {
+            this.loadJson();
+            this.readJson();
+
+        } catch (JSONException e) {
+            throw new DataException(String.format("Unable to read JSON at path %s: %s", this.filePath, e.getMessage()));
+        }
     }
 
     public void write() throws IOException, DataException {
@@ -58,6 +65,10 @@ public class ArbitraryDataMetadata {
         writer.close();
     }
 
+    public void delete() throws IOException {
+        Files.delete(this.filePath);
+    }
+
 
     protected void loadJson() throws IOException {
         File metadataFile = new File(this.filePath.toString());
@@ -65,7 +76,7 @@ public class ArbitraryDataMetadata {
             throw new IOException(String.format("Metadata file doesn't exist: %s", this.filePath.toString()));
         }
 
-        this.jsonString = new String(Files.readAllBytes(this.filePath));
+        this.jsonString = new String(Files.readAllBytes(this.filePath), StandardCharsets.UTF_8);
     }
 
 

src/main/java/org/qortal/arbitrary/metadata/ArbitraryDataMetadataCache.java

@@ -1,5 +1,6 @@
 package org.qortal.arbitrary.metadata;
 
+import org.json.JSONException;
 import org.json.JSONObject;
 import org.qortal.repository.DataException;
 import org.qortal.utils.Base58;
@@ -22,7 +23,7 @@ public class ArbitraryDataMetadataCache extends ArbitraryDataQortalMetadata {
     }
 
     @Override
-    protected void readJson() throws DataException {
+    protected void readJson() throws DataException, JSONException {
         if (this.jsonString == null) {
             throw new DataException("Patch JSON string is null");
         }

src/main/java/org/qortal/arbitrary/metadata/ArbitraryDataMetadataPatch.java

@@ -3,6 +3,7 @@ package org.qortal.arbitrary.metadata;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.json.JSONArray;
+import org.json.JSONException;
 import org.json.JSONObject;
 import org.qortal.arbitrary.ArbitraryDataDiff.*;
 import org.qortal.repository.DataException;
@@ -40,7 +41,7 @@ public class ArbitraryDataMetadataPatch extends ArbitraryDataQortalMetadata {
     }
 
     @Override
-    protected void readJson() throws DataException {
+    protected void readJson() throws DataException, JSONException {
         if (this.jsonString == null) {
             throw new DataException("Patch JSON string is null");
         }

src/main/java/org/qortal/arbitrary/metadata/ArbitraryDataQortalMetadata.java

@@ -2,12 +2,14 @@ package org.qortal.arbitrary.metadata;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.json.JSONException;
 import org.qortal.repository.DataException;
 
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -46,20 +48,6 @@ public class ArbitraryDataQortalMetadata extends ArbitraryDataMetadata {
         return null;
     }
 
-    protected void readJson() throws DataException {
-        // To be overridden
-    }
-
-    protected void buildJson() {
-        // To be overridden
-    }
-
-
-    @Override
-    public void read() throws IOException, DataException {
-        this.loadJson();
-        this.readJson();
-    }
 
     @Override
     public void write() throws IOException, DataException {
@@ -82,7 +70,7 @@ public class ArbitraryDataQortalMetadata extends ArbitraryDataMetadata {
             throw new IOException(String.format("Patch file doesn't exist: %s", path.toString()));
         }
 
-        this.jsonString = new String(Files.readAllBytes(path));
+        this.jsonString = new String(Files.readAllBytes(path), StandardCharsets.UTF_8);
     }
 
 
@@ -94,9 +82,4 @@ public class ArbitraryDataQortalMetadata extends ArbitraryDataMetadata {
         }
     }
 
-
-    public String getJsonString() {
-        return this.jsonString;
-    }
-
 }

src/main/java/org/qortal/arbitrary/metadata/ArbitraryDataTransactionMetadata.java

@@ -1,11 +1,13 @@
 package org.qortal.arbitrary.metadata;
 
 import org.json.JSONArray;
+import org.json.JSONException;
 import org.json.JSONObject;
 import org.qortal.arbitrary.misc.Category;
 import org.qortal.repository.DataException;
 import org.qortal.utils.Base58;
 
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -19,9 +21,11 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
     private String description;
     private List<String> tags;
     private Category category;
+    private List<String> files;
+    private String mimeType;
 
     private static int MAX_TITLE_LENGTH = 80;
-    private static int MAX_DESCRIPTION_LENGTH = 500;
+    private static int MAX_DESCRIPTION_LENGTH = 240;
     private static int MAX_TAG_LENGTH = 20;
     private static int MAX_TAGS_COUNT = 5;
 
@@ -31,7 +35,7 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
     }
 
     @Override
-    protected void readJson() throws DataException {
+    protected void readJson() throws DataException, JSONException {
         if (this.jsonString == null) {
             throw new DataException("Transaction metadata JSON string is null");
         }
@@ -77,6 +81,24 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
             }
             this.chunks = chunksList;
         }
+
+        List<String> filesList = new ArrayList<>();
+        if (metadata.has("files")) {
+            JSONArray files = metadata.getJSONArray("files");
+            if (files != null) {
+                for (int i=0; i<files.length(); i++) {
+                    String tag = files.getString(i);
+                    if (tag != null) {
+                        filesList.add(tag);
+                    }
+                }
+            }
+            this.files = filesList;
+        }
+
+        if (metadata.has("mimeType")) {
+            this.mimeType = metadata.getString("mimeType");
+        }
     }
 
     @Override
@@ -111,6 +133,18 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
         }
         outer.put("chunks", chunks);
 
+        JSONArray files = new JSONArray();
+        if (this.files != null) {
+            for (String file : this.files) {
+                files.put(file);
+            }
+        }
+        outer.put("files", files);
+
+        if (this.mimeType != null && !this.mimeType.isEmpty()) {
+            outer.put("mimeType", this.mimeType);
+        }
+
         this.jsonString = outer.toString(2);
         LOGGER.trace("Transaction metadata: {}", this.jsonString);
     }
@@ -156,6 +190,22 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
         return this.category;
     }
 
+    public void setFiles(List<String> files) {
+        this.files = files;
+    }
+
+    public List<String> getFiles() {
+        return this.files;
+    }
+
+    public void setMimeType(String mimeType) {
+        this.mimeType = mimeType;
+    }
+
+    public String getMimeType() {
+        return this.mimeType;
+    }
+
     public boolean containsChunk(byte[] chunk) {
         for (byte[] c : this.chunks) {
             if (Arrays.equals(c, chunk)) {
@@ -168,6 +218,25 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
 
     // Static helper methods
 
+    public static String trimUTF8String(String string, int maxLength) {
+        byte[] inputBytes = string.getBytes(StandardCharsets.UTF_8);
+        int length = Math.min(inputBytes.length, maxLength);
+        byte[] outputBytes = new byte[length];
+
+        System.arraycopy(inputBytes, 0, outputBytes, 0, length);
+        String result = new String(outputBytes, StandardCharsets.UTF_8);
+
+        // check if last character is truncated
+        int lastIndex = result.length() - 1;
+
+        if (lastIndex > 0 && result.charAt(lastIndex) != string.charAt(lastIndex)) {
+            // last character is truncated so remove the last character
+            return result.substring(0, lastIndex);
+        }
+
+        return result;
+    }
+
     public static String limitTitle(String title) {
         if (title == null) {
             return null;
@@ -176,7 +245,7 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
             return null;
         }
 
-        return title.substring(0, Math.min(title.length(), MAX_TITLE_LENGTH));
+        return trimUTF8String(title, MAX_TITLE_LENGTH);
     }
 
     public static String limitDescription(String description) {
@@ -187,7 +256,7 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
             return null;
         }
 
-        return description.substring(0, Math.min(description.length(), MAX_DESCRIPTION_LENGTH));
+        return trimUTF8String(description, MAX_DESCRIPTION_LENGTH);
     }
 
     public static List<String> limitTags(List<String> tags) {

src/main/java/org/qortal/arbitrary/misc/Category.java

@@ -67,9 +67,12 @@ public enum Category {
     /**
      * Same as valueOf() but with fallback to UNCATEGORIZED if there's no match
      * @param name
-     * @return a Category (using UNCATEGORIZED if no match found)
+     * @return a Category (using UNCATEGORIZED if no match found), or null if null name passed
      */
     public static Category uncategorizedValueOf(String name) {
+        if (name == null) {
+            return null;
+        }
         try {
             return Category.valueOf(name);
         }

src/main/java/org/qortal/arbitrary/misc/Service.java

@@ -1,26 +1,66 @@
 package org.qortal.arbitrary.misc;
 
+import org.apache.commons.io.FilenameUtils;
 import org.json.JSONObject;
 import org.qortal.arbitrary.ArbitraryDataRenderer;
 import org.qortal.transaction.Transaction;
 import org.qortal.utils.FilesystemUtils;
 
+import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
 
 import static java.util.Arrays.stream;
 import static java.util.stream.Collectors.toMap;
 
 public enum Service {
-    AUTO_UPDATE(1, false, null, null),
-    ARBITRARY_DATA(100, false, null, null),
-    WEBSITE(200, true, null, null) {
+    AUTO_UPDATE(1, false, null, false, false, null),
+    ARBITRARY_DATA(100, false, null, false, false, null),
+    QCHAT_ATTACHMENT(120, true, 1024*1024L, true, false, null) {
         @Override
-        public ValidationResult validate(Path path) {
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
+            File[] files = path.toFile().listFiles();
+            // If already a single file, replace the list with one that contains that file only
+            if (files == null && path.toFile().isFile()) {
+                files = new File[] { path.toFile() };
+            }
+            // Now validate the file's extension
+            if (files != null && files[0] != null) {
+                final String extension = FilenameUtils.getExtension(files[0].getName()).toLowerCase();
+                // We must allow blank file extensions because these are used by data published from a plaintext or base64-encoded string
+                final List<String> allowedExtensions = Arrays.asList("zip", "pdf", "txt", "odt", "ods", "doc", "docx", "xls", "xlsx", "ppt", "pptx", "");
+                if (extension == null || !allowedExtensions.contains(extension)) {
+                    return ValidationResult.INVALID_FILE_EXTENSION;
+                }
+            }
+            return ValidationResult.OK;
+        }
+    },
+    QCHAT_ATTACHMENT_PRIVATE(121, true, 1024*1024L, true, true, null),
+    ATTACHMENT(130, false, 50*1024*1024L, true, false, null),
+    ATTACHMENT_PRIVATE(131, true, 50*1024*1024L, true, true, null),
+    FILE(140, false, null, true, false, null),
+    FILE_PRIVATE(141, true, null, true, true, null),
+    FILES(150, false, null, false, false, null),
+    CHAIN_DATA(160, true, 239L, true, false, null),
+    WEBSITE(200, true, null, false, false, null) {
+        @Override
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
             // Custom validation function to require an index HTML file in the root directory
             List<String> fileNames = ArbitraryDataRenderer.indexFiles();
             String[] files = path.toFile().list();
@@ -35,33 +75,125 @@ public enum Service {
             return ValidationResult.MISSING_INDEX_FILE;
         }
     },
-    GIT_REPOSITORY(300, false, null, null),
-    IMAGE(400, true, 10*1024*1024L, null),
-    THUMBNAIL(410, true, 500*1024L, null),
-    VIDEO(500, false, null, null),
-    AUDIO(600, false, null, null),
-    BLOG(700, false, null, null),
-    BLOG_POST(777, false, null, null),
-    BLOG_COMMENT(778, false, null, null),
-    DOCUMENT(800, false, null, null),
-    LIST(900, true, null, null),
-    PLAYLIST(910, true, null, null),
-    APP(1000, false, null, null),
-    METADATA(1100, false, null, null),
-    QORTAL_METADATA(1111, true, 10*1024L, Arrays.asList("title", "description", "tags"));
+    GIT_REPOSITORY(300, false, null, false, false, null),
+    IMAGE(400, true, 10*1024*1024L, true, false, null),
+    IMAGE_PRIVATE(401, true, 10*1024*1024L, true, true, null),
+    THUMBNAIL(410, true, 500*1024L, true, false, null),
+    QCHAT_IMAGE(420, true, 500*1024L, true, false, null),
+    VIDEO(500, false, null, true, false, null),
+    VIDEO_PRIVATE(501, true, null, true, true, null),
+    AUDIO(600, false, null, true, false, null),
+    AUDIO_PRIVATE(601, true, null, true, true, null),
+    QCHAT_AUDIO(610, true, 10*1024*1024L, true, false, null),
+    QCHAT_VOICE(620, true, 10*1024*1024L, true, false, null),
+    VOICE(630, true, 10*1024*1024L, true, false, null),
+    VOICE_PRIVATE(631, true, 10*1024*1024L, true, true, null),
+    PODCAST(640, false, null, true, false, null),
+    BLOG(700, false, null, false, false, null),
+    BLOG_POST(777, false, null, true, false, null),
+    BLOG_COMMENT(778, true, 500*1024L, true, false, null),
+    DOCUMENT(800, false, null, true, false, null),
+    DOCUMENT_PRIVATE(801, true, null, true, true, null),
+    LIST(900, true, null, true, false, null),
+    PLAYLIST(910, true, null, true, false, null),
+    APP(1000, true, 50*1024*1024L, false, false, null),
+    METADATA(1100, false, null, true, false, null),
+    JSON(1110, true, 25*1024L, true, false, null) {
+        @Override
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
+            // Require valid JSON
+            byte[] data = FilesystemUtils.getSingleFileContents(path, 25*1024);
+            String json = new String(data, StandardCharsets.UTF_8);
+            try {
+                objectMapper.readTree(json);
+                return ValidationResult.OK;
+            } catch (IOException e) {
+                return ValidationResult.INVALID_CONTENT;
+            }
+        }
+    },
+    GIF_REPOSITORY(1200, true, 25*1024*1024L, false, false, null) {
+        @Override
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
+            // Custom validation function to require .gif files only, and at least 1
+            int gifCount = 0;
+            File[] files = path.toFile().listFiles();
+            // If already a single file, replace the list with one that contains that file only
+            if (files == null && path.toFile().isFile()) {
+                files = new File[] { path.toFile() };
+            }
+            if (files != null) {
+                for (File file : files) {
+                    if (file.getName().equals(".qortal")) {
+                        continue;
+                    }
+                    if (file.isDirectory()) {
+                        return ValidationResult.DIRECTORIES_NOT_ALLOWED;
+                    }
+                    String extension = FilenameUtils.getExtension(file.getName()).toLowerCase();
+                    if (!Objects.equals(extension, "gif")) {
+                        return ValidationResult.INVALID_FILE_EXTENSION;
+                    }
+                    gifCount++;
+                }
+            }
+            if (gifCount == 0) {
+                return ValidationResult.MISSING_DATA;
+            }
+            return ValidationResult.OK;
+        }
+    },
+    STORE(1300, false, null, true, false, null),
+    PRODUCT(1310, false, null, true, false, null),
+    OFFER(1330, false, null, true, false, null),
+    COUPON(1340, false, null, true, false, null),
+    CODE(1400, false, null, true, false, null),
+    PLUGIN(1410, false, null, true, false, null),
+    EXTENSION(1420, false, null, true, false, null),
+    GAME(1500, false, null, false, false, null),
+    ITEM(1510, false, null, true, false, null),
+    NFT(1600, false, null, true, false, null),
+    DATABASE(1700, false, null, false, false, null),
+    SNAPSHOT(1710, false, null, false, false, null),
+    COMMENT(1800, true, 500*1024L, true, false, null),
+    CHAIN_COMMENT(1810, true, 239L, true, false, null),
+    MAIL(1900, true, 1024*1024L, true, false, null),
+    MAIL_PRIVATE(1901, true, 1024*1024L, true, true, null),
+    MESSAGE(1910, true, 1024*1024L, true, false, null),
+    MESSAGE_PRIVATE(1911, true, 1024*1024L, true, true, null);
 
     public final int value;
     private final boolean requiresValidation;
     private final Long maxSize;
+    private final boolean single;
+    private final boolean isPrivate;
     private final List<String> requiredKeys;
 
     private static final Map<Integer, Service> map = stream(Service.values())
             .collect(toMap(service -> service.value, service -> service));
 
-    Service(int value, boolean requiresValidation, Long maxSize, List<String> requiredKeys) {
+    // For JSON validation
+    private static final ObjectMapper objectMapper = new ObjectMapper();
+
+    private static final String encryptedDataPrefix = "qortalEncryptedData";
+    private static final String encryptedGroupDataPrefix = "qortalGroupEncryptedData";
+
+    Service(int value, boolean requiresValidation, Long maxSize, boolean single, boolean isPrivate, List<String> requiredKeys) {
         this.value = value;
         this.requiresValidation = requiresValidation;
         this.maxSize = maxSize;
+        this.single = single;
+        this.isPrivate = isPrivate;
         this.requiredKeys = requiredKeys;
     }
 
@@ -70,7 +202,9 @@ public enum Service {
             return ValidationResult.OK;
         }
 
-        byte[] data = FilesystemUtils.getSingleFileContents(path);
+        // Load the first 25KB of data. This only needs to be long enough to check the prefix
+        // and also to allow for possible additional future validation of smaller files.
+        byte[] data = FilesystemUtils.getSingleFileContents(path, 25*1024);
         long size = FilesystemUtils.getDirectorySize(path);
 
         // Validate max size if needed
@@ -80,6 +214,22 @@ public enum Service {
             }
         }
 
+        // Validate file count if needed
+        if (this.single && data == null) {
+            return ValidationResult.INVALID_FILE_COUNT;
+        }
+
+        // Validate private data for single file resources
+        if (this.single) {
+            String dataString = new String(data, StandardCharsets.UTF_8);
+            if (this.isPrivate && !dataString.startsWith(encryptedDataPrefix) && !dataString.startsWith(encryptedGroupDataPrefix)) {
+                return ValidationResult.DATA_NOT_ENCRYPTED;
+            }
+            if (!this.isPrivate && (dataString.startsWith(encryptedDataPrefix) || dataString.startsWith(encryptedGroupDataPrefix))) {
+                return ValidationResult.DATA_ENCRYPTED;
+            }
+        }
+
         // Validate required keys if needed
         if (this.requiredKeys != null) {
             if (data == null) {
@@ -98,7 +248,12 @@ public enum Service {
     }
 
     public boolean isValidationRequired() {
-        return this.requiresValidation;
+        // We must always validate single file resources, to ensure they are actually a single file
+        return this.requiresValidation || this.single;
+    }
+
+    public boolean isPrivate() {
+        return this.isPrivate;
     }
 
     public static Service valueOf(int value) {
@@ -106,15 +261,53 @@ public enum Service {
     }
 
     public static JSONObject toJsonObject(byte[] data) {
-        String dataString = new String(data);
+        String dataString = new String(data, StandardCharsets.UTF_8);
         return new JSONObject(dataString);
     }
 
+    public static List<Service> publicServices() {
+        List<Service> privateServices = new ArrayList<>();
+        for (Service service : Service.values()) {
+            if (!service.isPrivate) {
+                privateServices.add(service);
+            }
+        }
+        return privateServices;
+    }
+
+    /**
+     * Fetch a list of Service objects that require encrypted data.
+     *
+     * These can ultimately be used to help inform the cleanup manager
+     * on the best order to delete files when the node runs out of space.
+     * Public data should be given priority over private data (unless
+     * this node is part of a data market contract for that data - this
+     * isn't developed yet).
+     *
+     * @return a list of Service objects that require encrypted data.
+     */
+    public static List<Service> privateServices() {
+        List<Service> privateServices = new ArrayList<>();
+        for (Service service : Service.values()) {
+            if (service.isPrivate) {
+                privateServices.add(service);
+            }
+        }
+        return privateServices;
+    }
+
     public enum ValidationResult {
         OK(1),
         MISSING_KEYS(2),
         EXCEEDS_SIZE_LIMIT(3),
-        MISSING_INDEX_FILE(4);
+        MISSING_INDEX_FILE(4),
+        DIRECTORIES_NOT_ALLOWED(5),
+        INVALID_FILE_EXTENSION(6),
+        MISSING_DATA(7),
+        INVALID_FILE_COUNT(8),
+        INVALID_CONTENT(9),
+        DATA_NOT_ENCRYPTED(10),
+        DATA_ENCRYPTED(10);
 
         public final int value;
 

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

@@ -27,6 +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;
@@ -88,7 +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;
 
@@ -134,7 +136,7 @@ public class Block {
 	}
 
 	/** Lazy-instantiated expanded info on block's online accounts. */
-	private static class ExpandedAccount {
+	public static class ExpandedAccount {
 		private final RewardShareData rewardShareData;
 		private final int sharePercent;
 		private final boolean isRecipientAlsoMinter;
@@ -167,6 +169,13 @@ public class Block {
 			}
 		}
 
+		public Account getMintingAccount() {
+			return this.mintingAccount;
+		}
+		public Account getRecipientAccount() {
+			return this.recipientAccount;
+		}
+
 		/**
 		 * Returns share bin for expanded account.
 		 * <p>
@@ -183,8 +192,11 @@ 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;
 
@@ -197,6 +209,11 @@ 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
@@ -221,11 +238,10 @@ 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;
 
@@ -347,18 +363,36 @@ 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();
+		int height = parentBlockData.getHeight() + 1;
+		long timestamp = calcTimestamp(parentBlockData, minter.getPublicKey(), minterLevel);
+		long onlineAccountsTimestamp = OnlineAccountsManager.getCurrentOnlineAccountTimestamp();
+
+		// Fetch our list of online accounts, removing any that are missing a nonce
+		List<OnlineAccountData> onlineAccounts = OnlineAccountsManager.getInstance().getOnlineAccounts(onlineAccountsTimestamp);
+		onlineAccounts.removeIf(a -> a.getNonce() == null || a.getNonce() < 0);
+
+		// After feature trigger, remove any online accounts that are level 0
+		if (height >= BlockChain.getInstance().getOnlineAccountMinterLevelValidationHeight()) {
+			onlineAccounts.removeIf(a -> {
+				try {
+					return Account.getRewardShareEffectiveMintingLevel(repository, a.getPublicKey()) == 0;
+				} catch (DataException e) {
+					// Something went wrong, so remove the account
+					return true;
+				}
+			});
+		}
+
+		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.
@@ -369,10 +403,6 @@ 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
@@ -389,29 +419,43 @@ 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
+		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;
 
 		int atCount = 0;
 		long atFees = 0;
@@ -613,6 +657,10 @@ public class Block {
 		return this.atStates;
 	}
 
+	public byte[] getAtStatesHash() {
+		return this.atStatesHash;
+	}
+
 	/**
 	 * Return expanded info on block's online accounts.
 	 * <p>
@@ -1005,6 +1053,15 @@ public class Block {
 		if (onlineRewardShares == null)
 			return ValidationResult.ONLINE_ACCOUNT_UNKNOWN;
 
+		// After feature trigger, require all online account minters to be greater than level 0
+		if (this.getBlockData().getHeight() >= BlockChain.getInstance().getOnlineAccountMinterLevelValidationHeight()) {
+			List<ExpandedAccount> expandedAccounts = this.getExpandedAccounts();
+			for (ExpandedAccount account : expandedAccounts) {
+				if (account.getMintingAccount().getEffectiveMintingLevel() == 0)
+					return ValidationResult.ONLINE_ACCOUNTS_INVALID;
+			}
+		}
+
 		// If block is past a certain age then we simply assume the signatures were correct
 		long signatureRequirementThreshold = NTP.getTime() - BlockChain.getInstance().getOnlineAccountSignaturesMinLifetime();
 		if (this.blockData.getTimestamp() < signatureRequirementThreshold)
@@ -1013,49 +1070,64 @@ 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)
+		final int signaturesLength = Transformer.SIGNATURE_LENGTH;
+		final int noncesLength = onlineRewardShares.size() * Transformer.INT_LENGTH;
+
+		// We expect nonces to be appended to the online accounts signatures
+		if (this.blockData.getOnlineAccountsSignatures().length != signaturesLength + noncesLength)
 			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
+		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);
+		// 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);
-
-			// 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;
-
-			// 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;
+			OnlineAccountData onlineAccountData = new OnlineAccountData(onlineTimestamp, null, publicKey, nonce);
+			onlineAccounts.add(onlineAccountData);
 		}
 
+		// Remove those already validated & cached by online accounts manager - no need to re-validate them
+		OnlineAccountsManager.getInstance().removeKnown(onlineAccounts, onlineTimestamp);
+
+		// Validate the rest
+		for (OnlineAccountData onlineAccount : onlineAccounts)
+			if (!OnlineAccountsManager.getInstance().verifyMemoryPoW(onlineAccount, null))
+				return ValidationResult.ONLINE_ACCOUNT_NONCE_INCORRECT;
+
+		// Cache the valid online accounts as they will likely be needed for the next block
+		OnlineAccountsManager.getInstance().addBlocksOnlineAccounts(onlineAccounts, onlineTimestamp);
+
+		// 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;
@@ -1202,6 +1274,7 @@ 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
@@ -1394,6 +1467,9 @@ public class Block {
 			if (this.blockData.getHeight() == 212937)
 				// Apply fix for block 212937
 				Block212937.processFix(this);
+
+			else if (this.blockData.getHeight() == BlockChain.getInstance().getSelfSponsorshipAlgoV1Height())
+				SelfSponsorshipAlgoV1Block.processAccountPenalties(this);
 		}
 
 		// We're about to (test-)process a batch of transactions,
@@ -1426,9 +1502,6 @@ 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();
 	}
@@ -1453,19 +1526,23 @@ public class Block {
 		// Batch update in repository
 		repository.getAccountRepository().modifyMintedBlockCounts(allUniqueExpandedAccounts.stream().map(AccountData::getAddress).collect(Collectors.toList()), +1);
 
+		// Keep track of level bumps in case we need to apply to other entries
+		Map<String, Integer> bumpedAccounts = new HashMap<>();
+
 		// Local changes and also checks for level bump
 		for (AccountData accountData : allUniqueExpandedAccounts) {
 			// Adjust count locally (in Java)
 			accountData.setBlocksMinted(accountData.getBlocksMinted() + 1);
 			LOGGER.trace(() -> String.format("Block minter %s up to %d minted block%s", accountData.getAddress(), accountData.getBlocksMinted(), (accountData.getBlocksMinted() != 1 ? "s" : "")));
 
-			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment();
+			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment() + accountData.getBlocksMintedPenalty();
 
 			for (int newLevel = maximumLevel; newLevel >= 0; --newLevel)
 				if (effectiveBlocksMinted >= cumulativeBlocksByLevel.get(newLevel)) {
 					if (newLevel > accountData.getLevel()) {
 						// Account has increased in level!
 						accountData.setLevel(newLevel);
+						bumpedAccounts.put(accountData.getAddress(), newLevel);
 						repository.getAccountRepository().setLevel(accountData);
 						LOGGER.trace(() -> String.format("Block minter %s bumped to level %d", accountData.getAddress(), accountData.getLevel()));
 					}
@@ -1473,6 +1550,25 @@ public class Block {
 					break;
 				}
 		}
+
+		// Also bump other entries if need be
+		if (!bumpedAccounts.isEmpty()) {
+			for (ExpandedAccount expandedAccount : expandedAccounts) {
+				Integer newLevel = bumpedAccounts.get(expandedAccount.mintingAccountData.getAddress());
+				if (newLevel != null && expandedAccount.mintingAccountData.getLevel() != newLevel) {
+					expandedAccount.mintingAccountData.setLevel(newLevel);
+					LOGGER.trace("Also bumped {} to level {}", expandedAccount.mintingAccountData.getAddress(), newLevel);
+				}
+
+				if (!expandedAccount.isRecipientAlsoMinter) {
+					newLevel = bumpedAccounts.get(expandedAccount.recipientAccountData.getAddress());
+					if (newLevel != null && expandedAccount.recipientAccountData.getLevel() != newLevel) {
+						expandedAccount.recipientAccountData.setLevel(newLevel);
+						LOGGER.trace("Also bumped {} to level {}", expandedAccount.recipientAccountData.getAddress(), newLevel);
+					}
+				}
+			}
+		}
 	}
 
 	protected void processBlockRewards() throws DataException {
@@ -1590,12 +1686,14 @@ public class Block {
 					transactionData.getSignature());
 			this.repository.getBlockRepository().save(blockTransactionData);
 
-			// Update transaction's height in repository
+			// Update transaction's height in repository and local transactionData
 			transactionRepository.updateBlockHeight(transactionData.getSignature(), this.blockData.getHeight());
-
-			// Update local transactionData's height too
 			transaction.getTransactionData().setBlockHeight(this.blockData.getHeight());
 
+			// Update transaction's sequence in repository and local transactionData
+			transactionRepository.updateBlockSequence(transactionData.getSignature(), sequence);
+			transaction.getTransactionData().setBlockSequence(sequence);
+
 			// No longer unconfirmed
 			transactionRepository.confirmTransaction(transactionData.getSignature());
 
@@ -1632,6 +1730,9 @@ public class Block {
 				// Revert fix for block 212937
 				Block212937.orphanFix(this);
 
+			else if (this.blockData.getHeight() == BlockChain.getInstance().getSelfSponsorshipAlgoV1Height())
+				SelfSponsorshipAlgoV1Block.orphanAccountPenalties(this);
+
 			// Block rewards, including transaction fees, removed after transactions undone
 			orphanBlockRewards();
 
@@ -1644,9 +1745,6 @@ 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 {
@@ -1682,6 +1780,9 @@ public class Block {
 
 				// Unset height
 				transactionRepository.updateBlockHeight(transactionData.getSignature(), null);
+
+				// Unset sequence
+				transactionRepository.updateBlockSequence(transactionData.getSignature(), null);
 			}
 
 			transactionRepository.deleteParticipants(transactionData);
@@ -1763,7 +1864,7 @@ public class Block {
 			accountData.setBlocksMinted(accountData.getBlocksMinted() - 1);
 			LOGGER.trace(() -> String.format("Block minter %s down to %d minted block%s", accountData.getAddress(), accountData.getBlocksMinted(), (accountData.getBlocksMinted() != 1 ? "s" : "")));
 
-			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment();
+			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment() + accountData.getBlocksMintedPenalty();
 
 			for (int newLevel = maximumLevel; newLevel >= 0; --newLevel)
 				if (effectiveBlocksMinted >= cumulativeBlocksByLevel.get(newLevel)) {
@@ -1883,13 +1984,72 @@ 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())
@@ -1907,7 +2067,7 @@ 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

@@ -68,11 +68,18 @@ public class BlockChain {
 		atFindNextTransactionFix,
 		newBlockSigHeight,
 		shareBinFix,
+		sharesByLevelV2Height,
+		rewardShareLimitTimestamp,
 		calcChainWeightTimestamp,
-		newConsensusTimestamp,
 		transactionV5Timestamp,
 		transactionV6Timestamp,
-		disableReferenceTimestamp
+		disableReferenceTimestamp,
+		increaseOnlineAccountsDifficultyTimestamp,
+		onlineAccountMinterLevelValidationHeight,
+		selfSponsorshipAlgoV1Height,
+		feeValidationFixTimestamp,
+		chatReferenceTimestamp,
+		arbitraryOptionalFeeTimestamp;
 	}
 
 	// Custom transaction fees
@@ -94,6 +101,13 @@ public class BlockChain {
 	/** Whether only one registered name is allowed per account. */
 	private boolean oneNamePerAccount = false;
 
+	/** Checkpoints */
+	public static class Checkpoint {
+		public int height;
+		public String signature;
+	}
+	private List<Checkpoint> checkpoints;
+
 	/** Block rewards by block height */
 	public static class RewardByHeight {
 		public int height;
@@ -103,23 +117,48 @@ 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>
@@ -157,7 +196,7 @@ 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. */
@@ -165,6 +204,20 @@ 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;
+
+	/** Snapshot timestamp for self sponsorship algo V1 */
+	private long selfSponsorshipAlgoV1SnapshotTimestamp;
+
+	/** 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. */
@@ -313,6 +366,16 @@ public class BlockChain {
 		return this.maxBlockSize;
 	}
 
+	// Online accounts
+	public long getOnlineAccountsModulusV2Timestamp() {
+		return this.onlineAccountsModulusV2Timestamp;
+	}
+
+	// Self sponsorship algo
+	public long getSelfSponsorshipAlgoV1SnapshotTimestamp() {
+		return this.selfSponsorshipAlgoV1SnapshotTimestamp;
+	}
+
 	/** Returns true if approval-needing transaction types require a txGroupId other than NO_GROUP. */
 	public boolean getRequireGroupForApproval() {
 		return this.requireGroupForApproval;
@@ -326,16 +389,28 @@ public class BlockChain {
 		return this.oneNamePerAccount;
 	}
 
+	public List<Checkpoint> getCheckpoints() {
+		return this.checkpoints;
+	}
+
 	public List<RewardByHeight> getBlockRewardsByHeight() {
 		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() {
@@ -346,14 +421,18 @@ 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;
 	}
@@ -366,8 +445,8 @@ public class BlockChain {
 		return this.minAccountLevelToRewardShare;
 	}
 
-	public int getMaxRewardSharesPerMintingAccount() {
-		return this.maxRewardSharesPerMintingAccount;
+	public int getMaxRewardSharesPerFounderMintingAccount() {
+		return this.maxRewardSharesPerFounderMintingAccount;
 	}
 
 	public int getFounderEffectiveMintingLevel() {
@@ -400,12 +479,16 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.shareBinFix.name()).intValue();
 	}
 
-	public long getCalcChainWeightTimestamp() {
-		return this.featureTriggers.get(FeatureTrigger.calcChainWeightTimestamp.name()).longValue();
+	public int getSharesByLevelV2Height() {
+		return this.featureTriggers.get(FeatureTrigger.sharesByLevelV2Height.name()).intValue();
 	}
 
-	public long getNewConsensusTimestamp() {
-		return this.featureTriggers.get(FeatureTrigger.newConsensusTimestamp.name()).longValue();
+	public long getRewardShareLimitTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.rewardShareLimitTimestamp.name()).longValue();
+	}
+
+	public long getCalcChainWeightTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.calcChainWeightTimestamp.name()).longValue();
 	}
 
 	public long getTransactionV5Timestamp() {
@@ -420,6 +503,31 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.disableReferenceTimestamp.name()).longValue();
 	}
 
+	public long getIncreaseOnlineAccountsDifficultyTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.increaseOnlineAccountsDifficultyTimestamp.name()).longValue();
+	}
+
+	public int getSelfSponsorshipAlgoV1Height() {
+		return this.featureTriggers.get(FeatureTrigger.selfSponsorshipAlgoV1Height.name()).intValue();
+	}
+
+	public long getOnlineAccountMinterLevelValidationHeight() {
+		return this.featureTriggers.get(FeatureTrigger.onlineAccountMinterLevelValidationHeight.name()).intValue();
+	}
+
+	public long getFeeValidationFixTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.feeValidationFixTimestamp.name()).longValue();
+	}
+
+	public long getChatReferenceTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.chatReferenceTimestamp.name()).longValue();
+	}
+
+	public long getArbitraryOptionalFeeTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.arbitraryOptionalFeeTimestamp.name()).longValue();
+	}
+
+
 	// More complex getters for aspects that change by height or timestamp
 
 	public long getRewardAtHeight(int ourHeight) {
@@ -448,6 +556,23 @@ public class BlockChain {
 		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)
@@ -456,11 +581,14 @@ 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");
@@ -497,13 +625,22 @@ 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)");
 	}
 
@@ -519,23 +656,34 @@ 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);
 	}
 
 	/**
@@ -547,6 +695,7 @@ public class BlockChain {
 
 		boolean isTopOnly = Settings.getInstance().isTopOnly();
 		boolean archiveEnabled = Settings.getInstance().isArchiveEnabled();
+		boolean isLite = Settings.getInstance().isLite();
 		boolean canBootstrap = Settings.getInstance().getBootstrap();
 		boolean needsArchiveRebuild = false;
 		BlockData chainTip;
@@ -567,22 +716,44 @@ public class BlockChain {
 					}
 				}
 			}
+
+			// Validate checkpoints
+			// Limited to topOnly nodes for now, in order to reduce risk, and to solve a real-world problem with divergent topOnly nodes
+			// TODO: remove the isTopOnly conditional below once this feature has had more testing time
+			if (isTopOnly && !isLite) {
+				List<Checkpoint> checkpoints = BlockChain.getInstance().getCheckpoints();
+				for (Checkpoint checkpoint : checkpoints) {
+					BlockData blockData = repository.getBlockRepository().fromHeight(checkpoint.height);
+					if (blockData == null) {
+						// Try the archive
+						blockData = repository.getBlockArchiveRepository().fromHeight(checkpoint.height);
+					}
+					if (blockData == null) {
+						LOGGER.trace("Couldn't find block for height {}", checkpoint.height);
+						// This is likely due to the block being pruned, so is safe to ignore.
+						// Continue, as there might be other blocks we can check more definitively.
+						continue;
+					}
+
+					byte[] signature = Base58.decode(checkpoint.signature);
+					if (!Arrays.equals(signature, blockData.getSignature())) {
+						LOGGER.info("Error: block at height {} with signature {} doesn't match checkpoint sig: {}. Bootstrapping...", checkpoint.height, Base58.encode(blockData.getSignature()), checkpoint.signature);
+						needsArchiveRebuild = true;
+						break;
+					}
+					LOGGER.info("Block at height {} matches checkpoint signature", blockData.getHeight());
+				}
+			}
+
 		}
 
-		boolean hasBlocks = (chainTip != null && chainTip.getHeight() > 1);
+		// Check first block is Genesis Block
+		if (!isGenesisBlockValid() || needsArchiveRebuild) {
+			try {
+				rebuildBlockchain();
 
-		if (isTopOnly && hasBlocks) {
-			// Top-only mode is enabled and we have blocks, so it's possible that the genesis block has been pruned
-			// It's best not to validate it, and there's no real need to
-		} else {
-			// Check first block is Genesis Block
-			if (!isGenesisBlockValid() || needsArchiveRebuild) {
-				try {
-					rebuildBlockchain();
-
-				} catch (InterruptedException e) {
-					throw new DataException(String.format("Interrupted when trying to rebuild blockchain: %s", e.getMessage()));
-				}
+			} catch (InterruptedException e) {
+				throw new DataException(String.format("Interrupted when trying to rebuild blockchain: %s", e.getMessage()));
 			}
 		}
 
@@ -591,9 +762,7 @@ public class BlockChain {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			repository.checkConsistency();
 
-			// Set the number of blocks to validate based on the pruned state of the chain
-			// If pruned, subtract an extra 10 to allow room for error
-			int blocksToValidate = (isTopOnly || archiveEnabled) ? Settings.getInstance().getPruneBlockLimit() - 10 : 1440;
+			int blocksToValidate = Math.min(Settings.getInstance().getPruneBlockLimit() - 10, 1440);
 
 			int startHeight = Math.max(repository.getBlockRepository().getBlockchainHeight() - blocksToValidate, 1);
 			BlockData detachedBlockData = repository.getBlockRepository().getDetachedBlockSignature(startHeight);
@@ -702,6 +871,9 @@ public class BlockChain {
 				BlockData orphanBlockData = repository.getBlockRepository().fromHeight(height);
 
 				while (height > targetHeight) {
+					if (Controller.isStopping()) {
+						return false;
+					}
 					LOGGER.info(String.format("Forcably orphaning block %d", height));
 
 					Block block = new Block(repository, orphanBlockData);

src/main/java/org/qortal/block/SelfSponsorshipAlgoV1Block.java

@@ -0,0 +1,133 @@
+package org.qortal.block;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.account.SelfSponsorshipAlgoV1;
+import org.qortal.api.model.AccountPenaltyStats;
+import org.qortal.crypto.Crypto;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.account.AccountPenaltyData;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.utils.Base58;
+
+import java.nio.charset.StandardCharsets;
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * Self Sponsorship AlgoV1 Block
+ * <p>
+ * Selected block for the initial run on the "self sponsorship detection algorithm"
+ */
+public final class SelfSponsorshipAlgoV1Block {
+
+	private static final Logger LOGGER = LogManager.getLogger(SelfSponsorshipAlgoV1Block.class);
+
+
+	private SelfSponsorshipAlgoV1Block() {
+		/* Do not instantiate */
+	}
+
+	public static void processAccountPenalties(Block block) throws DataException {
+		LOGGER.info("Running algo for block processing - this will take a while...");
+		logPenaltyStats(block.repository);
+		long startTime = System.currentTimeMillis();
+		Set<AccountPenaltyData> penalties = getAccountPenalties(block.repository, -5000000);
+		block.repository.getAccountRepository().updateBlocksMintedPenalties(penalties);
+		long totalTime = System.currentTimeMillis() - startTime;
+		String hash = getHash(penalties.stream().map(p -> p.getAddress()).collect(Collectors.toList()));
+		LOGGER.info("{} penalty addresses processed (hash: {}). Total time taken: {} seconds", penalties.size(), hash, (int)(totalTime / 1000.0f));
+		logPenaltyStats(block.repository);
+
+		int updatedCount = updateAccountLevels(block.repository, penalties);
+		LOGGER.info("Account levels updated for {} penalty addresses", updatedCount);
+	}
+
+	public static void orphanAccountPenalties(Block block) throws DataException {
+		LOGGER.info("Running algo for block orphaning - this will take a while...");
+		logPenaltyStats(block.repository);
+		long startTime = System.currentTimeMillis();
+		Set<AccountPenaltyData> penalties = getAccountPenalties(block.repository, 5000000);
+		block.repository.getAccountRepository().updateBlocksMintedPenalties(penalties);
+		long totalTime = System.currentTimeMillis() - startTime;
+		String hash = getHash(penalties.stream().map(p -> p.getAddress()).collect(Collectors.toList()));
+		LOGGER.info("{} penalty addresses orphaned (hash: {}). Total time taken: {} seconds", penalties.size(), hash, (int)(totalTime / 1000.0f));
+		logPenaltyStats(block.repository);
+
+		int updatedCount = updateAccountLevels(block.repository, penalties);
+		LOGGER.info("Account levels updated for {} penalty addresses", updatedCount);
+	}
+
+	public static Set<AccountPenaltyData> getAccountPenalties(Repository repository, int penalty) throws DataException {
+		final long snapshotTimestamp = BlockChain.getInstance().getSelfSponsorshipAlgoV1SnapshotTimestamp();
+		Set<AccountPenaltyData> penalties = new LinkedHashSet<>();
+		List<String> addresses = repository.getTransactionRepository().getConfirmedRewardShareCreatorsExcludingSelfShares();
+		for (String address : addresses) {
+			//System.out.println(String.format("address: %s", address));
+			SelfSponsorshipAlgoV1 selfSponsorshipAlgoV1 = new SelfSponsorshipAlgoV1(repository, address, snapshotTimestamp, false);
+			selfSponsorshipAlgoV1.run();
+			//System.out.println(String.format("Penalty addresses: %d", selfSponsorshipAlgoV1.getPenaltyAddresses().size()));
+
+			for (String penaltyAddress : selfSponsorshipAlgoV1.getPenaltyAddresses()) {
+				penalties.add(new AccountPenaltyData(penaltyAddress, penalty));
+			}
+		}
+		return penalties;
+	}
+
+	private static int updateAccountLevels(Repository repository, Set<AccountPenaltyData> accountPenalties) throws DataException {
+		final List<Integer> cumulativeBlocksByLevel = BlockChain.getInstance().getCumulativeBlocksByLevel();
+		final int maximumLevel = cumulativeBlocksByLevel.size() - 1;
+
+		int updatedCount = 0;
+
+		for (AccountPenaltyData penaltyData : accountPenalties) {
+			AccountData accountData = repository.getAccountRepository().getAccount(penaltyData.getAddress());
+			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment() + accountData.getBlocksMintedPenalty();
+
+			// Shortcut for penalties
+			if (effectiveBlocksMinted < 0) {
+				accountData.setLevel(0);
+				repository.getAccountRepository().setLevel(accountData);
+				updatedCount++;
+				LOGGER.trace(() -> String.format("Block minter %s dropped to level %d", accountData.getAddress(), accountData.getLevel()));
+				continue;
+			}
+
+			for (int newLevel = maximumLevel; newLevel >= 0; --newLevel) {
+				if (effectiveBlocksMinted >= cumulativeBlocksByLevel.get(newLevel)) {
+					accountData.setLevel(newLevel);
+					repository.getAccountRepository().setLevel(accountData);
+					updatedCount++;
+					LOGGER.trace(() -> String.format("Block minter %s increased to level %d", accountData.getAddress(), accountData.getLevel()));
+					break;
+				}
+			}
+		}
+
+		return updatedCount;
+	}
+
+	private static void logPenaltyStats(Repository repository) {
+		try {
+			LOGGER.info(getPenaltyStats(repository));
+
+		} catch (DataException e) {}
+	}
+
+	private static AccountPenaltyStats getPenaltyStats(Repository repository) throws DataException {
+		List<AccountData> accounts = repository.getAccountRepository().getPenaltyAccounts();
+		return AccountPenaltyStats.fromAccounts(accounts);
+	}
+
+	public static String getHash(List<String> penaltyAddresses) {
+		if (penaltyAddresses == null || penaltyAddresses.isEmpty()) {
+			return null;
+		}
+		Collections.sort(penaltyAddresses);
+		return Base58.encode(Crypto.digest(StringUtils.join(penaltyAddresses).getBytes(StandardCharsets.UTF_8)));
+	}
+
+}

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 {
@@ -277,4 +293,77 @@ public class AutoUpdate extends Thread {
 		}
 	}
 
+	public static boolean attemptRestart() {
+		LOGGER.info(String.format("Restarting node..."));
+
+		// Give repository a chance to backup in case things go badly wrong (if enabled)
+		if (Settings.getInstance().getRepositoryBackupInterval() > 0) {
+			try {
+				// Timeout if the database isn't ready for backing up after 60 seconds
+				long timeout = 60 * 1000L;
+				RepositoryManager.backup(true, "backup", timeout);
+
+			} catch (TimeoutException e) {
+				LOGGER.info("Attempt to backup repository failed due to timeout: {}", e.getMessage());
+				// Continue with the node restart anyway...
+			}
+		}
+
+		// Call ApplyUpdate to end this process (unlocking current JAR so it can be replaced)
+		String javaHome = System.getProperty("java.home");
+		LOGGER.debug(String.format("Java home: %s", javaHome));
+
+		Path javaBinary = Paths.get(javaHome, "bin", "java");
+		LOGGER.debug(String.format("Java binary: %s", javaBinary));
+
+		try {
+			List<String> javaCmd = new ArrayList<>();
+			// Java runtime binary itself
+			javaCmd.add(javaBinary.toString());
+
+			// 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"));
+
+			// Call ApplyUpdate using JAR
+			javaCmd.addAll(Arrays.asList("-cp", JAR_FILENAME, ApplyUpdate.class.getCanonicalName()));
+
+			// Add command-line args saved from start-up
+			String[] savedArgs = Controller.getInstance().getSavedArgs();
+			if (savedArgs != null)
+				javaCmd.addAll(Arrays.asList(savedArgs));
+
+			LOGGER.info(String.format("Restarting node with: %s", String.join(" ", javaCmd)));
+
+			SysTray.getInstance().showMessage(Translator.INSTANCE.translate("SysTray", "AUTO_UPDATE"), //TODO
+					Translator.INSTANCE.translate("SysTray", "APPLYING_UPDATE_AND_RESTARTING"), //TODO
+					MessageType.INFO);
+
+			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; // restarting node OK
+		} catch (Exception e) {
+			LOGGER.error(String.format("Failed to restart node: %s", e.getMessage()));
+
+			return true; // repo was okay, even if applying update failed
+		}
+	}
+
 }

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

@@ -35,6 +35,8 @@ import org.qortal.transaction.Transaction;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 
+import static org.junit.Assert.assertNotNull;
+
 // Minting new blocks
 
 public class BlockMinter extends Thread {
@@ -61,13 +63,12 @@ public class BlockMinter extends Thread {
 	public void run() {
 		Thread.currentThread().setName("BlockMinter");
 
-		if (Settings.getInstance().isLite()) {
-			// Lite nodes do not mint
+		if (Settings.getInstance().isTopOnly() || Settings.getInstance().isLite()) {
+			// Top only and lite nodes do not sign blocks
 			return;
 		}
-
-		try (final Repository repository = RepositoryManager.getRepository()) {
-			if (Settings.getInstance().getWipeUnconfirmedOnStart()) {
+		if (Settings.getInstance().getWipeUnconfirmedOnStart()) {
+			try (final Repository repository = RepositoryManager.getRepository()) {
 				// Wipe existing unconfirmed transactions
 				List<TransactionData> unconfirmedTransactions = repository.getTransactionRepository().getUnconfirmedTransactions();
 
@@ -77,356 +78,385 @@ 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<>();
+
+		final boolean isSingleNodeTestnet = Settings.getInstance().isSingleNodeTestnet();
+
+		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.debug("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.
+					// It's faster on single node testnets, to allow lots of blocks to be minted quickly.
+					Thread.sleep(isSingleNodeTestnet ? 50 : 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.debug("Higher weight chain found in peers, so not signing a block this round");
-								LOGGER.debug("Time since detected: {}ms", 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
+					// Skip this check for single node testnets, since they definitely need to mint every block
+					byte[] previousBlockMinter = previousBlockData.getMinterPublicKey();
+					boolean mintedLastBlock = mintingAccountsData.stream().anyMatch(mintingAccount -> Arrays.equals(mintingAccount.getPublicKey(), previousBlockMinter));
+					if (mintedLastBlock && !isSingleNodeTestnet) {
+						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.info("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.debug("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;
+
+						Long unconfirmedStartTime = NTP.getTime();
+
+						// Add unconfirmed transactions
+						addUnconfirmedTransactions(repository, newBlock);
+
+						LOGGER.info(String.format("Adding %d unconfirmed transactions took %d ms", newBlock.getTransactions().size(), (NTP.getTime()-unconfirmedStartTime)));
+
+						// 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();
+						} catch (ArithmeticException 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);
 		}
 	}
 
@@ -458,6 +488,9 @@ public class BlockMinter extends Thread {
 		// Sign to create block's signature, needed by Block.isValid()
 		newBlock.sign();
 
+		// User-defined limit per block
+		int limit = Settings.getInstance().getMaxTransactionsPerBlock();
+
 		// Attempt to add transactions until block is full, or we run out
 		// If a transaction makes the block invalid then skip it and it'll either expire or be in next block.
 		for (TransactionData transactionData : unconfirmedTransactions) {
@@ -470,6 +503,12 @@ public class BlockMinter extends Thread {
 				LOGGER.debug(() -> String.format("Skipping invalid transaction %s during block minting", Base58.encode(transactionData.getSignature())));
 				newBlock.deleteTransaction(transactionData);
 			}
+
+			// User-defined limit per block
+			List<Transaction> transactions = newBlock.getTransactions();
+			if (transactions != null && transactions.size() >= limit) {
+				break;
+			}
 		}
 	}
 
@@ -488,6 +527,21 @@ public class BlockMinter extends Thread {
 
 		PrivateKeyAccount mintingAccount = mintingAndOnlineAccounts[0];
 
+		Block block = mintTestingBlockRetainingTimestamps(repository, mintingAccount);
+		assertNotNull("Minted block must not be null", block);
+
+		return block;
+	}
+
+	public static Block mintTestingBlockUnvalidated(Repository repository, PrivateKeyAccount... mintingAndOnlineAccounts) throws DataException {
+		if (!BlockChain.getInstance().isTestChain())
+			throw new DataException("Ignoring attempt to mint testing block for non-test chain!");
+
+		// Ensure mintingAccount is 'online' so blocks can be minted
+		OnlineAccountsManager.getInstance().ensureTestingAccountsOnline(mintingAndOnlineAccounts);
+
+		PrivateKeyAccount mintingAccount = mintingAndOnlineAccounts[0];
+
 		return mintTestingBlockRetainingTimestamps(repository, mintingAccount);
 	}
 
@@ -495,6 +549,8 @@ public class BlockMinter extends Thread {
 		BlockData previousBlockData = repository.getBlockRepository().getLastBlock();
 
 		Block newBlock = Block.mint(repository, previousBlockData, mintingAccount);
+		if (newBlock == null)
+			return null;
 
 		// Make sure we're the only thread modifying the blockchain
 		ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
@@ -557,18 +613,23 @@ 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

@@ -29,6 +29,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.bouncycastle.jce.provider.BouncyCastleProvider;
 import org.bouncycastle.jsse.provider.BouncyCastleJsseProvider;
+import org.qortal.account.Account;
 import org.qortal.api.ApiService;
 import org.qortal.api.DomainMapService;
 import org.qortal.api.GatewayService;
@@ -45,8 +46,8 @@ import org.qortal.data.account.AccountData;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.naming.NameData;
-import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.network.PeerData;
+import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.ChatTransactionData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.event.Event;
@@ -113,6 +114,7 @@ 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
 
@@ -316,6 +318,10 @@ 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) {
@@ -397,12 +403,12 @@ public class Controller extends Thread {
 			RepositoryManager.setRequestedCheckpoint(Boolean.TRUE);
 
 			try (final Repository repository = RepositoryManager.getRepository()) {
-				RepositoryManager.archive(repository);
-				RepositoryManager.prune(repository);
+				RepositoryManager.rebuildTransactionSequences(repository);
+				ArbitraryDataCacheManager.getInstance().buildArbitraryResourcesCache(repository, false);
 			}
 		} catch (DataException e) {
-			// If exception has no cause then repository is in use by some other process.
-			if (e.getCause() == null) {
+			// If exception has no cause or message then repository is in use by some other process.
+			if (e.getCause() == null && e.getMessage() == null) {
 				LOGGER.info("Repository in use by another process?");
 				Gui.getInstance().fatalError("Repository issue", "Repository in use by another process?");
 			} else {
@@ -436,6 +442,26 @@ public class Controller extends Thread {
 			}
 		}
 
+		try (Repository repository = RepositoryManager.getRepository()) {
+			if (RepositoryManager.needsTransactionSequenceRebuild(repository)) {
+				// Don't allow the node to start if transaction sequences haven't been built yet
+				// This is needed to handle a case when bootstrapping
+				LOGGER.error("Database upgrade needed. Please restart the core to complete the upgrade process.");
+				Gui.getInstance().fatalError("Database upgrade needed", "Please restart the core to complete the upgrade process.");
+				return;
+			}
+			if (ArbitraryDataCacheManager.getInstance().needsArbitraryResourcesCacheRebuild(repository)) {
+				// Don't allow the node to start if arbitrary resources cache hasn't been built yet
+				// This is needed to handle a case when bootstrapping
+				LOGGER.error("Database upgrade needed. Please restart the core to complete the upgrade process.");
+				Gui.getInstance().fatalError("Database upgrade needed", "Please restart the core to complete the upgrade process.");
+				return;
+			}
+		} catch (DataException e) {
+			LOGGER.error("Error checking transaction sequences in repository", e);
+			return;
+		}
+
 		// Import current trade bot states and minting accounts if they exist
 		Controller.importRepositoryData();
 
@@ -479,6 +505,7 @@ public class Controller extends Thread {
 		LOGGER.info("Starting arbitrary-transaction controllers");
 		ArbitraryDataManager.getInstance().start();
 		ArbitraryDataFileManager.getInstance().start();
+		ArbitraryDataCacheManager.getInstance().start();
 		ArbitraryDataBuildManager.getInstance().start();
 		ArbitraryDataCleanupManager.getInstance().start();
 		ArbitraryDataStorageManager.getInstance().start();
@@ -496,6 +523,9 @@ 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();
@@ -552,6 +582,7 @@ 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();
@@ -649,10 +680,15 @@ 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
@@ -715,45 +751,27 @@ public class Controller extends Thread {
 		return lastMisbehaved != null && lastMisbehaved > NTP.getTime() - MISBEHAVIOUR_COOLOFF;
 	};
 
-	/** True if peer has unknown height or lower height. */
-	public static final Predicate<Peer> hasShorterBlockchain = peer -> {
-		BlockData ourLatestBlockData = getInstance().getChainTip();
-		int ourHeight = ourLatestBlockData.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;
-
-		return false;
-	};
-
 	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 -> {
@@ -761,6 +779,28 @@ public class Controller extends Thread {
 		return peer.isAtLeastVersion(minPeerVersion) == false;
 	};
 
+	public static final Predicate<Peer> hasInvalidSigner = peer -> {
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		if (peerChainTipData == null)
+			return true;
+
+		try (Repository repository = RepositoryManager.getRepository()) {
+			return Account.getRewardShareEffectiveMintingLevel(repository, peerChainTipData.getMinterPublicKey()) == 0;
+		} catch (DataException e) {
+			return true;
+		}
+	};
+
+	public static final Predicate<Peer> wasRecentlyTooDivergent = peer -> {
+		Long now = NTP.getTime();
+		Long peerLastTooDivergentTime = peer.getLastTooDivergentTime();
+		if (now == null || peerLastTooDivergentTime == null)
+			return false;
+
+		// Exclude any peers that were TOO_DIVERGENT in the last 5 mins
+		return (now - peerLastTooDivergentTime < 5 * 60 * 1000L);
+	};
+
 	private long getRandomRepositoryMaintenanceInterval() {
 		final long minInterval = Settings.getInstance().getRepositoryMaintenanceMinInterval();
 		final long maxInterval = Settings.getInstance().getRepositoryMaintenanceMaxInterval();
@@ -805,23 +845,24 @@ 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 (Settings.getInstance().isLite()) {
 				actionText = Translator.INSTANCE.translate("SysTray", "LITE_NODE");
 				SysTray.getInstance().setTrayIcon(4);
 			}
-			else if (this.isMintingPossible) {
-				actionText = Translator.INSTANCE.translate("SysTray", "MINTING_ENABLED");
-				SysTray.getInstance().setTrayIcon(2);
-			}
 			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);
 			}
@@ -829,6 +870,10 @@ 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);
@@ -838,6 +883,12 @@ public class Controller extends Thread {
 		String tooltip = String.format("%s - %d %s", actionText, numberOfPeers, connectionsText);
 		if (!Settings.getInstance().isLite()) {
 			tooltip = tooltip.concat(String.format(" - %s %d", heightText, height));
+
+			final Integer blocksRemaining = Synchronizer.getInstance().getBlocksRemaining();
+			if (blocksRemaining != null && blocksRemaining > 0) {
+				String blocksRemainingText = Translator.INSTANCE.translate("SysTray", "BLOCKS_REMAINING");
+				tooltip = tooltip.concat(String.format(" - %d %s", blocksRemaining, blocksRemainingText));
+			}
 		}
 		tooltip = tooltip.concat(String.format("\n%s: %s", Translator.INSTANCE.translate("SysTray", "BUILD_VERSION"), this.buildVersion));
 		SysTray.getInstance().setToolTipText(tooltip);
@@ -866,6 +917,7 @@ public class Controller extends Thread {
 				if (now >= transaction.getDeadline()) {
 					LOGGER.debug(() -> String.format("Deleting expired, unconfirmed transaction %s", Base58.encode(transactionData.getSignature())));
 					repository.getTransactionRepository().delete(transactionData);
+					this.onExpiredTransaction(transactionData);
 					deletedCount++;
 				}
 			}
@@ -896,6 +948,9 @@ 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();
@@ -905,6 +960,7 @@ public class Controller extends Thread {
 				LOGGER.info("Shutting down arbitrary-transaction controllers");
 				ArbitraryDataManager.getInstance().shutdown();
 				ArbitraryDataFileManager.getInstance().shutdown();
+				ArbitraryDataCacheManager.getInstance().shutdown();
 				ArbitraryDataBuildManager.getInstance().shutdown();
 				ArbitraryDataCleanupManager.getInstance().shutdown();
 				ArbitraryDataStorageManager.getInstance().shutdown();
@@ -1007,8 +1063,7 @@ public class Controller extends Thread {
 		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
@@ -1176,6 +1231,21 @@ public class Controller extends Thread {
 		});
 	}
 
+	/**
+	 * Callback for when we've deleted an expired, unconfirmed transaction.
+	 * <p>
+	 * @implSpec performs actions in a new thread
+	 */
+	public void onExpiredTransaction(TransactionData transactionData) {
+		this.callbackExecutor.execute(() -> {
+
+			// If this is an ARBITRARY transaction, we may need to update the cache
+			if (transactionData.getType() == TransactionType.ARBITRARY) {
+				ArbitraryDataManager.getInstance().onExpiredArbitraryTransaction((ArbitraryTransactionData)transactionData);
+			}
+		});
+	}
+
 	public void onPeerHandshakeCompleted(Peer peer) {
 		// Only send if outbound
 		if (peer.isOutbound()) {
@@ -1215,6 +1285,10 @@ 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;
@@ -1231,20 +1305,12 @@ public class Controller extends Thread {
 				TransactionImporter.getInstance().onNetworkTransactionSignaturesMessage(peer, message);
 				break;
 
-			case GET_ONLINE_ACCOUNTS:
-				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsMessage(peer, message);
+			case GET_ONLINE_ACCOUNTS_V3:
+				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsV3Message(peer, message);
 				break;
 
-			case ONLINE_ACCOUNTS:
-				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsMessage(peer, message);
-				break;
-
-			case GET_ONLINE_ACCOUNTS_V2:
-				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsV2Message(peer, message);
-				break;
-
-			case ONLINE_ACCOUNTS_V2:
-				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsV2Message(peer, message);
+			case ONLINE_ACCOUNTS_V3:
+				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsV3Message(peer, message);
 				break;
 
 			case GET_ARBITRARY_DATA:
@@ -1345,9 +1411,24 @@ public class Controller extends Thread {
 			// If we have no block data, we should check the archive in case it's there
 			if (blockData == null) {
 				if (Settings.getInstance().isArchiveEnabled()) {
-					byte[] bytes = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, true, repository);
-					if (bytes != null) {
-						CachedBlockMessage blockMessage = new CachedBlockMessage(bytes);
+					Triple<byte[], Integer, Integer> serializedBlock = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, true, repository);
+					if (serializedBlock != null) {
+						byte[] bytes = serializedBlock.getA();
+						Integer serializationVersion = serializedBlock.getB();
+
+						Message blockMessage;
+						switch (serializationVersion) {
+							case 1:
+								blockMessage = new CachedBlockMessage(bytes);
+								break;
+
+							case 2:
+								blockMessage = new CachedBlockV2Message(bytes);
+								break;
+
+							default:
+								return;
+						}
 						blockMessage.setId(message.getId());
 
 						// This call also causes the other needed data to be pulled in from repository
@@ -1370,8 +1451,10 @@ 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");
@@ -1420,11 +1503,15 @@ 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");
 
@@ -1480,7 +1567,9 @@ 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");
@@ -1555,18 +1644,59 @@ public class Controller extends Thread {
 			// 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 (!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.debug("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();
@@ -1582,8 +1712,8 @@ public class Controller extends Thread {
 				// 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));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// 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");
@@ -1618,8 +1748,8 @@ public class Controller extends Thread {
 				// 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));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// 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");
@@ -1662,8 +1792,8 @@ public class Controller extends Thread {
 				// 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));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// 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");
@@ -1699,8 +1829,8 @@ public class Controller extends Thread {
 				// 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));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// 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");
@@ -1734,8 +1864,8 @@ public class Controller extends Thread {
 				// 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));
 
-				// We'll send empty block summaries message as it's very short
-				Message nameUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// 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");
@@ -1783,14 +1913,14 @@ 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;
 			}
@@ -1818,6 +1948,10 @@ public class Controller extends Thread {
 		if (latestBlockData == null || latestBlockData.getTimestamp() < minLatestBlockTimestamp)
 			return false;
 
+		if (Settings.getInstance().isSingleNodeTestnet())
+			// Single node testnets won't have peers, so we can assume up to date from this point
+			return true;
+
 		// Needs a mutable copy of the unmodifiableList
 		List<Peer> peers = new ArrayList<>(Network.getInstance().getImmutableHandshakedPeers());
 		if (peers == null)

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

@@ -0,0 +1,74 @@
+package org.qortal.controller;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.api.DevProxyService;
+import org.qortal.repository.DataException;
+import org.qortal.settings.Settings;
+
+public class DevProxyManager {
+
+    protected static final Logger LOGGER = LogManager.getLogger(DevProxyManager.class);
+
+    private static DevProxyManager instance;
+
+    private boolean running = false;
+
+    private String sourceHostAndPort = "127.0.0.1:5173"; // Default for React/Vite
+
+    private DevProxyManager() {
+
+    }
+
+    public static DevProxyManager getInstance() {
+        if (instance == null)
+            instance = new DevProxyManager();
+
+        return instance;
+    }
+
+    public void start() throws DataException {
+        synchronized(this) {
+            if (this.running) {
+                // Already running
+                return;
+            }
+
+            LOGGER.info(String.format("Starting developer proxy service on port %d", Settings.getInstance().getDevProxyPort()));
+            DevProxyService devProxyService = DevProxyService.getInstance();
+            devProxyService.start();
+            this.running = true;
+        }
+    }
+
+    public void stop() {
+        synchronized(this) {
+            if (!this.running) {
+                // Not running
+                return;
+            }
+
+            LOGGER.info(String.format("Shutting down developer proxy service"));
+            DevProxyService devProxyService = DevProxyService.getInstance();
+            devProxyService.stop();
+            this.running = false;
+        }
+    }
+
+    public void setSourceHostAndPort(String sourceHostAndPort) {
+        this.sourceHostAndPort = sourceHostAndPort;
+    }
+
+    public String getSourceHostAndPort() {
+        return this.sourceHostAndPort;
+    }
+
+    public Integer getPort() {
+        return Settings.getInstance().getDevProxyPort();
+    }
+
+    public boolean isRunning() {
+        return this.running;
+    }
+
+}

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 || t.getService() == 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, true);
+
+            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

@@ -19,7 +19,6 @@ 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;
@@ -54,7 +53,8 @@ public class Synchronizer extends Thread {
 	/** Maximum number of block signatures we ask from peer in one go */
 	private static final int MAXIMUM_REQUEST_SIZE = 200; // XXX move to Settings?
 
-	private static final long RECOVERY_MODE_TIMEOUT = 10 * 60 * 1000L; // ms
+	/** Maximum number of consecutive failed sync attempts before marking peer as misbehaved */
+	private static final int MAX_CONSECUTIVE_FAILED_SYNC_ATTEMPTS = 3;
 
 
 	private boolean running;
@@ -76,12 +76,14 @@ public class Synchronizer extends Thread {
 	private volatile boolean isSynchronizing = false;
 	/** Temporary estimate of synchronization progress for SysTray use. */
 	private volatile int syncPercent = 0;
+	/** Temporary estimate of blocks remaining for SysTray use. */
+	private volatile int blocksRemaining = 0;
 
 	private static volatile boolean requestSync = false;
 	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;
 
@@ -171,8 +173,8 @@ 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;
 			}
@@ -181,6 +183,18 @@ public class Synchronizer extends Thread {
 		}
 	}
 
+	public Integer getBlocksRemaining() {
+		synchronized (this.syncLock) {
+			// Report as 0 blocks remaining if the latest block is within the last 60 mins
+			final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
+			if (Controller.getInstance().isUpToDate(minLatestBlockTimestamp)) {
+				return 0;
+			}
+
+			return this.isSynchronizing ? this.blocksRemaining : null;
+		}
+	}
+
 	public void requestSync() {
 		requestSync = true;
 	}
@@ -199,8 +213,6 @@ public class Synchronizer extends Thread {
 		if (this.isSynchronizing)
 			return true;
 
-		boolean isNewConsensusActive = NTP.getTime() >= BlockChain.getInstance().getNewConsensusTimestamp();
-
 		// Needs a mutable copy of the unmodifiableList
 		List<Peer> peers = new ArrayList<>(Network.getInstance().getImmutableHandshakedPeers());
 
@@ -229,25 +241,22 @@ public class Synchronizer extends Thread {
 		if (peers.size() < Settings.getInstance().getMinBlockchainPeers())
 			return true;
 
-		if (isNewConsensusActive)
-			// Disregard peers with a shorter chain
-			peers.removeIf(Controller.hasShorterBlockchain);
-
 		// Disregard peers that have no block signature or the same block signature as us
 		peers.removeIf(Controller.hasNoOrSameBlock);
 
 		// Disregard peers that are on the same block as last sync attempt and we didn't like their chain
 		peers.removeIf(Controller.hasInferiorChainTip);
 
+		// Disregard peers that have a block with an invalid signer
+		peers.removeIf(Controller.hasInvalidSigner);
+
 		final int peersBeforeComparison = peers.size();
 
-		if (!isNewConsensusActive) {
-			// Request recent block summaries from the remaining peers, and locate our common block with each
-			Synchronizer.getInstance().findCommonBlocksWithPeers(peers);
+		// Request recent block summaries from the remaining peers, and locate our common block with each
+		Synchronizer.getInstance().findCommonBlocksWithPeers(peers);
 
-			// Compare the peers against each other, and against our chain, which will return an updated list excluding those without common blocks
-			peers = Synchronizer.getInstance().comparePeers(peers);
-		}
+		// Compare the peers against each other, and against our chain, which will return an updated list excluding those without common blocks
+		peers = Synchronizer.getInstance().comparePeers(peers);
 
 		// We may have added more inferior chain tips when comparing peers, so remove any peers that are currently on those chains
 		peers.removeIf(Controller.hasInferiorChainTip);
@@ -290,7 +299,7 @@ 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) {
@@ -320,7 +329,7 @@ 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);
 
@@ -328,7 +337,8 @@ 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;
 				}
@@ -349,7 +359,7 @@ 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);
 
@@ -377,8 +387,7 @@ 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));
 			}
@@ -405,9 +414,10 @@ public class Synchronizer extends Thread {
 					timePeersLastAvailable = NTP.getTime();
 
 				// If enough time has passed, enter recovery mode, which lifts some restrictions on who we can sync with and when we can mint
-				if (NTP.getTime() - timePeersLastAvailable > RECOVERY_MODE_TIMEOUT) {
+				long recoveryModeTimeout = Settings.getInstance().getRecoveryModeTimeout();
+				if (NTP.getTime() - timePeersLastAvailable > recoveryModeTimeout) {
 					if (recoveryMode == false) {
-						LOGGER.info(String.format("Peers have been unavailable for %d minutes. Entering recovery mode...", RECOVERY_MODE_TIMEOUT/60/1000));
+						LOGGER.info(String.format("Peers have been unavailable for %d minutes. Entering recovery mode...", recoveryModeTimeout/60/1000));
 						recoveryMode = true;
 					}
 				}
@@ -521,13 +531,13 @@ 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<>();
@@ -625,7 +635,7 @@ 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;
 						}
@@ -636,16 +646,18 @@ 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);
@@ -693,6 +705,8 @@ 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
@@ -731,8 +745,9 @@ 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();
 
@@ -829,7 +844,7 @@ 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)
@@ -848,6 +863,10 @@ 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) {
@@ -855,8 +874,7 @@ 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) {
@@ -875,17 +893,16 @@ 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;
 				}
 			}
@@ -898,10 +915,9 @@ 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;
 				}
 			}
@@ -936,13 +952,13 @@ 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);
 
@@ -993,13 +1009,8 @@ public class Synchronizer extends Thread {
 						return SynchronizationResult.NOTHING_TO_DO;
 					}
 
-					boolean isNewConsensusActive = NTP.getTime() >= BlockChain.getInstance().getNewConsensusTimestamp();
-
 					// Unless we're doing a forced sync, we might need to compare blocks after common block
-					boolean isBlockComparisonNeeded = isNewConsensusActive
-							? ourInitialHeight == peerHeight
-							: ourInitialHeight > commonBlockHeight;
-					if (!force && isBlockComparisonNeeded) {
+					if (!force && ourInitialHeight > commonBlockHeight) {
 						SynchronizationResult chainCompareResult = compareChains(repository, commonBlockData, ourLatestBlockData, peer, peerHeight, peerBlockSummaries);
 						if (chainCompareResult != SynchronizationResult.OK)
 							return chainCompareResult;
@@ -1110,6 +1121,7 @@ public class Synchronizer extends Thread {
 			// If common block is too far behind us then we're on massively different forks so give up.
 			if (!force && testHeight < ourHeight - MAXIMUM_COMMON_DELTA) {
 				LOGGER.info(String.format("Blockchain too divergent with peer %s", peer));
+				peer.setLastTooDivergentTime(NTP.getTime());
 				return SynchronizationResult.TOO_DIVERGENT;
 			}
 
@@ -1119,6 +1131,9 @@ public class Synchronizer extends Thread {
 			testHeight = Math.max(testHeight - step, 1);
 		}
 
+		// Peer not considered too divergent
+		peer.setLastTooDivergentTime(0L);
+
 		// Prepend test block's summary as first block summary, as summaries returned are *after* test block
 		BlockSummaryData testBlockSummary = new BlockSummaryData(testBlockData);
 		blockSummariesFromCommon.add(0, testBlockSummary);
@@ -1200,56 +1215,27 @@ public class Synchronizer extends Thread {
 				peerBlockSummaries.addAll(moreBlockSummaries);
 			}
 
-			boolean isNewConsensusActive = NTP.getTime() >= BlockChain.getInstance().getNewConsensusTimestamp();
-			if (isNewConsensusActive) {
-				int parentHeight = ourLatestBlockData.getHeight() - 1;
+			// Fetch our corresponding block summaries
+			List<BlockSummaryData> ourBlockSummaries = repository.getBlockRepository().getBlockSummaries(commonBlockHeight + 1, ourLatestBlockData.getHeight());
 
-				BlockSummaryData ourLatestBlockSummary = new BlockSummaryData(ourLatestBlockData);
-				byte[] ourParentBlockSignature = ourLatestBlockData.getReference();
+			// Populate minter account levels for both lists of block summaries
+			populateBlockSummariesMinterLevels(repository, ourBlockSummaries);
+			populateBlockSummariesMinterLevels(repository, peerBlockSummaries);
 
-				BlockSummaryData peersLatestBlockSummary = peerBlockSummaries.get(peerBlockSummaries.size() - 1);
-				byte[] peersParentBlockSignature = peerBlockSummaries.size() > 1
-						? peerBlockSummaries.get(peerBlockSummaries.size() - 1 - 1).getSignature()
-						: commonBlockSig;
+			final int mutualHeight = commonBlockHeight + Math.min(ourBlockSummaries.size(), peerBlockSummaries.size());
 
-				// Populate minter account levels for both lists of block summaries
-				populateBlockSummariesMinterLevels(repository, Collections.singletonList(ourLatestBlockSummary));
-				populateBlockSummariesMinterLevels(repository, Collections.singletonList(peersLatestBlockSummary));
+			// Calculate cumulative chain weights of both blockchain subsets, from common block to highest mutual block.
+			BigInteger ourChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockSig, ourBlockSummaries, mutualHeight);
+			BigInteger peerChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockSig, peerBlockSummaries, mutualHeight);
 
-				BigInteger ourChainWeight = Block.calcBlockWeight(parentHeight, ourParentBlockSignature, ourLatestBlockSummary);
-				BigInteger peerChainWeight = Block.calcBlockWeight(parentHeight, peersParentBlockSignature, peersLatestBlockSummary);
+			NumberFormat accurateFormatter = new DecimalFormat("0.################E0");
+			LOGGER.debug(String.format("commonBlockHeight: %d, commonBlockSig: %.8s, ourBlockSummaries.size(): %d, peerBlockSummaries.size(): %d", commonBlockHeight, Base58.encode(commonBlockSig), ourBlockSummaries.size(), peerBlockSummaries.size()));
+			LOGGER.debug(String.format("Our chain weight: %s, peer's chain weight: %s (higher is better)", accurateFormatter.format(ourChainWeight), accurateFormatter.format(peerChainWeight)));
 
-				NumberFormat accurateFormatter = new DecimalFormat("0.################E0");
-				LOGGER.debug(String.format("Our chain weight: %s, peer's chain weight: %s (higher is better)", accurateFormatter.format(ourChainWeight), accurateFormatter.format(peerChainWeight)));
-
-				// If our blockchain has greater weight then don't synchronize with peer
-				if (ourChainWeight.compareTo(peerChainWeight) >= 0) {
-					LOGGER.debug(String.format("Not synchronizing with peer %s as we have better blockchain", peer));
-					return SynchronizationResult.INFERIOR_CHAIN;
-				}
-			} else {
-				// Fetch our corresponding block summaries
-				List<BlockSummaryData> ourBlockSummaries = repository.getBlockRepository().getBlockSummaries(commonBlockHeight + 1, ourLatestBlockData.getHeight());
-
-				// Populate minter account levels for both lists of block summaries
-				populateBlockSummariesMinterLevels(repository, ourBlockSummaries);
-				populateBlockSummariesMinterLevels(repository, peerBlockSummaries);
-
-				final int mutualHeight = commonBlockHeight + Math.min(ourBlockSummaries.size(), peerBlockSummaries.size());
-
-				// Calculate cumulative chain weights of both blockchain subsets, from common block to highest mutual block.
-				BigInteger ourChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockSig, ourBlockSummaries, mutualHeight);
-				BigInteger peerChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockSig, peerBlockSummaries, mutualHeight);
-
-				NumberFormat accurateFormatter = new DecimalFormat("0.################E0");
-				LOGGER.debug(String.format("commonBlockHeight: %d, commonBlockSig: %.8s, ourBlockSummaries.size(): %d, peerBlockSummaries.size(): %d", commonBlockHeight, Base58.encode(commonBlockSig), ourBlockSummaries.size(), peerBlockSummaries.size()));
-				LOGGER.debug(String.format("Our chain weight: %s, peer's chain weight: %s (higher is better)", accurateFormatter.format(ourChainWeight), accurateFormatter.format(peerChainWeight)));
-
-				// If our blockchain has greater weight then don't synchronize with peer
-				if (ourChainWeight.compareTo(peerChainWeight) >= 0) {
-					LOGGER.debug(String.format("Not synchronizing with peer %s as we have better blockchain", peer));
-					return SynchronizationResult.INFERIOR_CHAIN;
-				}
+			// If our blockchain has greater weight then don't synchronize with peer
+			if (ourChainWeight.compareTo(peerChainWeight) >= 0) {
+				LOGGER.debug(String.format("Not synchronizing with peer %s as we have better blockchain", peer));
+				return SynchronizationResult.INFERIOR_CHAIN;
 			}
 		}
 
@@ -1283,7 +1269,14 @@ 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;
 
@@ -1350,7 +1343,7 @@ 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;
@@ -1485,6 +1478,12 @@ public class Synchronizer extends Thread {
 
 			repository.saveChanges();
 
+			synchronized (this.syncLock) {
+				if (peer.getChainTipData() != null) {
+					this.blocksRemaining = peer.getChainTipData().getHeight() - newBlock.getBlockData().getHeight();
+				}
+			}
+
 			Controller.getInstance().onNewBlock(newBlock.getBlockData());
 		}
 
@@ -1580,6 +1579,12 @@ public class Synchronizer extends Thread {
 
 			repository.saveChanges();
 
+			synchronized (this.syncLock) {
+				if (peer.getChainTipData() != null) {
+					this.blocksRemaining = peer.getChainTipData().getHeight() - newBlock.getBlockData().getHeight();
+				}
+			}
+
 			Controller.getInstance().onNewBlock(newBlock.getBlockData());
 		}
 
@@ -1590,12 +1595,19 @@ 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 {
@@ -1614,8 +1626,20 @@ public class Synchronizer extends Thread {
 		Message getBlockMessage = new GetBlockMessage(signature);
 
 		Message message = peer.getResponse(getBlockMessage);
-		if (message == null)
+		if (message == null) {
+			peer.getPeerData().incrementFailedSyncCount();
+			if (peer.getPeerData().getFailedSyncCount() >= MAX_CONSECUTIVE_FAILED_SYNC_ATTEMPTS) {
+				// Several failed attempts, so mark peer as misbehaved
+				LOGGER.info("Marking peer {} as misbehaved due to {} failed sync attempts", peer, peer.getPeerData().getFailedSyncCount());
+				Network.getInstance().peerMisbehaved(peer);
+			}
 			return null;
+		}
+
+		// Reset failed sync count now that we have a block response
+		// FUTURE: we could move this to the end of the sync process, but to reduce risk this can be done
+		// at a later stage. For now we are only defending against serialization errors or no responses.
+		peer.getPeerData().setFailedSyncCount(0);
 
 		switch (message.getType()) {
 			case BLOCK: {

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

@@ -5,13 +5,17 @@ import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.ArbitraryDataBuildQueueItem;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.controller.Controller;
+import org.qortal.data.arbitrary.ArbitraryResourceStatus;
 import org.qortal.repository.DataException;
+import org.qortal.utils.ArbitraryTransactionUtils;
 import org.qortal.utils.NTP;
 
 import java.io.IOException;
 import java.util.Comparator;
 import java.util.Map;
 
+import static org.qortal.data.arbitrary.ArbitraryResourceStatus.Status.*;
+
 
 public class ArbitraryDataBuilderThread implements Runnable {
 
@@ -69,6 +73,14 @@ public class ArbitraryDataBuilderThread implements Runnable {
                         continue;
                     }
 
+                    // Get status before build
+                    ArbitraryResourceStatus arbitraryResourceStatus = ArbitraryTransactionUtils.getStatus(queueItem.getService(), queueItem.getResourceId(), queueItem.getIdentifier(), false, true);
+                    if (arbitraryResourceStatus.getStatus() == NOT_PUBLISHED) {
+                        // No point in building a non-existent resource
+                        this.removeFromQueue(queueItem);
+                        continue;
+                    }
+
                     // Set the start timestamp, to prevent other threads from building it at the same time
                     queueItem.prepareForBuild();
                 }

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

@@ -0,0 +1,236 @@
+package org.qortal.controller.arbitrary;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.api.resource.TransactionsResource;
+import org.qortal.controller.Controller;
+import org.qortal.data.arbitrary.ArbitraryResourceData;
+import org.qortal.data.transaction.ArbitraryTransactionData;
+import org.qortal.gui.SplashFrame;
+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.transaction.Transaction;
+import org.qortal.utils.Base58;
+
+import java.util.*;
+
+public class ArbitraryDataCacheManager extends Thread {
+
+    private static final Logger LOGGER = LogManager.getLogger(ArbitraryDataCacheManager.class);
+
+    private static ArbitraryDataCacheManager instance;
+    private volatile boolean isStopping = false;
+
+    /** Queue of arbitrary transactions that require cache updates */
+    private final List<ArbitraryTransactionData> updateQueue = Collections.synchronizedList(new ArrayList<>());
+
+
+    public static synchronized ArbitraryDataCacheManager getInstance() {
+        if (instance == null) {
+            instance = new ArbitraryDataCacheManager();
+        }
+
+        return instance;
+    }
+
+    @Override
+    public void run() {
+        Thread.currentThread().setName("Arbitrary Data Cache Manager");
+
+        try {
+            while (!Controller.isStopping()) {
+                Thread.sleep(500L);
+
+                // Process queue
+                processResourceQueue();
+            }
+        } catch (InterruptedException e) {
+            // Fall through to exit thread
+        }
+
+        // Clear queue before terminating thread
+        processResourceQueue();
+    }
+
+    public void shutdown() {
+        isStopping = true;
+        this.interrupt();
+    }
+
+
+    private void processResourceQueue() {
+        if (this.updateQueue.isEmpty()) {
+            // Nothing to do
+            return;
+        }
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            // Take a snapshot of resourceQueue, so we don't need to lock it while processing
+            List<ArbitraryTransactionData> resourceQueueCopy = List.copyOf(this.updateQueue);
+
+            for (ArbitraryTransactionData transactionData : resourceQueueCopy) {
+                // Best not to return when controller is stopping, as ideally we need to finish processing
+
+                LOGGER.debug(() -> String.format("Processing transaction %.8s in arbitrary resource queue...", Base58.encode(transactionData.getSignature())));
+
+                // Remove from the queue regardless of outcome
+                this.updateQueue.remove(transactionData);
+
+                // Update arbitrary resource caches
+                try {
+                    ArbitraryTransaction arbitraryTransaction = new ArbitraryTransaction(repository, transactionData);
+                    arbitraryTransaction.updateArbitraryResourceCache(repository);
+                    arbitraryTransaction.updateArbitraryMetadataCache(repository);
+                    repository.saveChanges();
+
+                    // Update status as separate commit, as this is more prone to failure
+                    arbitraryTransaction.updateArbitraryResourceStatus(repository);
+                    repository.saveChanges();
+
+                    LOGGER.debug(() -> String.format("Finished processing transaction %.8s in arbitrary resource queue...", Base58.encode(transactionData.getSignature())));
+
+                } catch (DataException e) {
+                    repository.discardChanges();
+                    LOGGER.error("Repository issue while updating arbitrary resource caches", e);
+                }
+            }
+        } catch (DataException e) {
+            LOGGER.error("Repository issue while processing arbitrary resource cache updates", e);
+        }
+    }
+
+    public void addToUpdateQueue(ArbitraryTransactionData transactionData) {
+        this.updateQueue.add(transactionData);
+        LOGGER.debug(() -> String.format("Transaction %.8s added to queue", Base58.encode(transactionData.getSignature())));
+    }
+
+    public boolean needsArbitraryResourcesCacheRebuild(Repository repository) throws DataException {
+        // Check if we have an entry in the cache for the oldest ARBITRARY transaction with a name
+        List<ArbitraryTransactionData> oldestCacheableTransactions = repository.getArbitraryRepository().getArbitraryTransactions(true, 1, 0, false);
+        if (oldestCacheableTransactions == null || oldestCacheableTransactions.isEmpty()) {
+            // No relevant arbitrary transactions yet on this chain
+            LOGGER.debug("No relevant arbitrary transactions exist to build cache from");
+            return false;
+        }
+        // We have an arbitrary transaction, so check if it's in the cache
+        ArbitraryTransactionData txn = oldestCacheableTransactions.get(0);
+        ArbitraryResourceData cachedResource = repository.getArbitraryRepository().getArbitraryResource(txn.getService(), txn.getName(), txn.getIdentifier());
+        if (cachedResource != null) {
+            // Earliest resource exists in the cache, so assume it has been built.
+            // We avoid checkpointing and prevent the node from starting up in the case of a rebuild failure, so
+            // we shouldn't ever be left in a partially rebuilt state.
+            LOGGER.debug("Arbitrary resources cache already built");
+            return false;
+        }
+
+        return true;
+    }
+
+    public boolean buildArbitraryResourcesCache(Repository repository, boolean forceRebuild) throws DataException {
+        if (Settings.getInstance().isLite()) {
+            // Lite nodes have no blockchain
+            return false;
+        }
+
+        try {
+            // Skip if already built
+            if (!needsArbitraryResourcesCacheRebuild(repository) && !forceRebuild) {
+                LOGGER.debug("Arbitrary resources cache already built");
+                return false;
+            }
+
+            LOGGER.info("Building arbitrary resources cache...");
+            SplashFrame.getInstance().updateStatus("Building QDN cache - please wait...");
+
+            final int batchSize = 100;
+            int offset = 0;
+
+            // Loop through all ARBITRARY transactions, and determine latest state
+            while (!Controller.isStopping()) {
+                LOGGER.info("Fetching arbitrary transactions {} - {}", offset, offset+batchSize-1);
+
+                List<byte[]> signatures = repository.getTransactionRepository().getSignaturesMatchingCriteria(null, null, null, List.of(Transaction.TransactionType.ARBITRARY), null, null, null, TransactionsResource.ConfirmationStatus.BOTH, batchSize, offset, false);
+                if (signatures.isEmpty()) {
+                    // Complete
+                    break;
+                }
+
+                // Expand signatures to transactions
+                for (byte[] signature : signatures) {
+                    ArbitraryTransactionData transactionData = (ArbitraryTransactionData) repository
+                            .getTransactionRepository().fromSignature(signature);
+
+                    if (transactionData.getService() == null) {
+                        // Unsupported service - ignore this resource
+                        continue;
+                    }
+
+                    // Update arbitrary resource caches
+                    ArbitraryTransaction arbitraryTransaction = new ArbitraryTransaction(repository, transactionData);
+                    arbitraryTransaction.updateArbitraryResourceCache(repository);
+                    arbitraryTransaction.updateArbitraryMetadataCache(repository);
+                    repository.saveChanges();
+                }
+                offset += batchSize;
+            }
+
+            // Now refresh all statuses
+            refreshArbitraryStatuses(repository);
+
+            LOGGER.info("Completed build of arbitrary resources cache.");
+            return true;
+        }
+        catch (DataException e) {
+            LOGGER.info("Unable to build arbitrary resources cache: {}. The database may have been left in an inconsistent state.", e.getMessage());
+
+            // Throw an exception so that the node startup is halted, allowing for a retry next time.
+            repository.discardChanges();
+            throw new DataException("Build of arbitrary resources cache failed.");
+        }
+    }
+
+    private boolean refreshArbitraryStatuses(Repository repository) throws DataException {
+        try {
+            LOGGER.info("Refreshing arbitrary resource statuses for locally hosted transactions...");
+            SplashFrame.getInstance().updateStatus("Refreshing statuses - please wait...");
+
+            final int batchSize = 100;
+            int offset = 0;
+
+            // Loop through all ARBITRARY transactions, and determine latest state
+            while (!Controller.isStopping()) {
+                LOGGER.info("Fetching hosted transactions {} - {}", offset, offset+batchSize-1);
+
+                List<ArbitraryTransactionData> hostedTransactions = ArbitraryDataStorageManager.getInstance().listAllHostedTransactions(repository, batchSize, offset);
+                if (hostedTransactions.isEmpty()) {
+                    // Complete
+                    break;
+                }
+
+                // Loop through hosted transactions
+                for (ArbitraryTransactionData transactionData : hostedTransactions) {
+
+                    // Determine status and update cache
+                    ArbitraryTransaction arbitraryTransaction = new ArbitraryTransaction(repository, transactionData);
+                    arbitraryTransaction.updateArbitraryResourceStatus(repository);
+                    repository.saveChanges();
+                }
+                offset += batchSize;
+            }
+
+            LOGGER.info("Completed refresh of arbitrary resource statuses.");
+            return true;
+        }
+        catch (DataException e) {
+            LOGGER.info("Unable to refresh arbitrary resource statuses: {}. The database may have been left in an inconsistent state.", e.getMessage());
+
+            // Throw an exception so that the node startup is halted, allowing for a retry next time.
+            repository.discardChanges();
+            throw new DataException("Refresh of arbitrary resource statuses failed.");
+        }
+    }
+
+}

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

@@ -11,10 +11,7 @@ import org.qortal.repository.RepositoryManager;
 import org.qortal.settings.Settings;
 import org.qortal.transaction.Transaction;
 import org.qortal.transaction.Transaction.TransactionType;
-import org.qortal.utils.ArbitraryTransactionUtils;
-import org.qortal.utils.Base58;
-import org.qortal.utils.FilesystemUtils;
-import org.qortal.utils.NTP;
+import org.qortal.utils.*;
 
 import java.io.File;
 import java.io.IOException;
@@ -137,7 +134,7 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 						// Fetch the transaction data
 						ArbitraryTransactionData arbitraryTransactionData = ArbitraryTransactionUtils.fetchTransactionData(repository, signature);
-						if (arbitraryTransactionData == null) {
+						if (arbitraryTransactionData == null || arbitraryTransactionData.getService() == null) {
 							continue;
 						}
 
@@ -204,7 +201,7 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 						if (completeFileExists && !allChunksExist) {
 							// We have the complete file but not the chunks, so let's convert it
-							LOGGER.info(String.format("Transaction %s has complete file but no chunks",
+							LOGGER.debug(String.format("Transaction %s has complete file but no chunks",
 									Base58.encode(arbitraryTransactionData.getSignature())));
 
 							ArbitraryTransactionUtils.convertFileToChunks(arbitraryTransactionData, now, STALE_FILE_TIMEOUT);
@@ -239,7 +236,7 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 					// Delete random data associated with name if we're over our storage limit for this name
 					// Use the DELETION_THRESHOLD, for the same reasons as above
-					for (String followedName : storageManager.followedNames()) {
+					for (String followedName : ListUtils.followedNames()) {
 						if (isStopping) {
 							return;
 						}
@@ -349,6 +346,10 @@ public class ArbitraryDataCleanupManager extends Thread {
 	/**
 	 * Iteratively walk through given directory and delete a single random file
 	 *
+	 * TODO: public data should be prioritized over private data
+	 * (unless this node is part of a data market contract for that data).
+	 * See: Service.privateServices() for a list of services containing private data.
+	 *
 	 * @param directory - the base directory
 	 * @return boolean - whether a file was deleted
 	 */
@@ -487,7 +488,7 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 				// Delete data relating to blocked names
 				String name = directory.getName();
-				if (name != null && storageManager.isNameBlocked(name)) {
+				if (name != null && ListUtils.isNameBlocked(name)) {
 					this.safeDeleteDirectory(directory, "blocked name");
 				}
 

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

@@ -20,6 +20,7 @@ import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 import org.qortal.settings.Settings;
 import org.qortal.utils.Base58;
+import org.qortal.utils.ListUtils;
 import org.qortal.utils.NTP;
 import org.qortal.utils.Triple;
 
@@ -67,6 +68,9 @@ 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() {
     }
@@ -120,19 +124,29 @@ public class ArbitraryDataFileListManager {
             }
         }
 
-        // Then allow another 5 attempts, each 5 minutes apart
-        if (timeSinceLastAttempt > 5 * 60 * 1000L) {
-            // We haven't tried for at least 5 minutes
+        // Then allow another 5 attempts, each 1 minute apart
+        if (timeSinceLastAttempt > 60 * 1000L) {
+            // We haven't tried for at least 1 minute
 
-            if (networkBroadcastCount < 5) {
-                // We've made less than 5 total attempts
+            if (networkBroadcastCount < 8) {
+                // We've made less than 8 total attempts
                 return true;
             }
         }
 
-        // From then on, only try once every 24 hours, to reduce network spam
-        if (timeSinceLastAttempt > 24 * 60 * 60 * 1000L) {
-            // We haven't tried for at least 24 hours
+        // Then allow another 8 attempts, each 15 minutes apart
+        if (timeSinceLastAttempt > 15 * 60 * 1000L) {
+            // We haven't tried for at least 15 minutes
+
+            if (networkBroadcastCount < 16) {
+                // We've made less than 16 total attempts
+                return true;
+            }
+        }
+
+        // From then on, only try once every 6 hours, to reduce network spam
+        if (timeSinceLastAttempt > 6 * 60 * 60 * 1000L) {
+            // We haven't tried for at least 6 hours
             return true;
         }
 
@@ -184,8 +198,8 @@ 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;
         }
 
@@ -245,8 +259,6 @@ public class ArbitraryDataFileListManager {
     // Lookup file lists by signature (and optionally hashes)
 
     public boolean fetchArbitraryDataFileList(ArbitraryTransactionData arbitraryTransactionData) {
-        byte[] digest = arbitraryTransactionData.getData();
-        byte[] metadataHash = arbitraryTransactionData.getMetadataHash();
         byte[] signature = arbitraryTransactionData.getSignature();
         String signature58 = Base58.encode(signature);
 
@@ -273,8 +285,7 @@ public class ArbitraryDataFileListManager {
 
         // Find hashes that we are missing
         try {
-            ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromHash(digest, signature);
-            arbitraryDataFile.setMetadataHash(metadataHash);
+            ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromTransactionData(arbitraryTransactionData);
             missingHashes = arbitraryDataFile.missingHashes();
         } catch (DataException e) {
             // Leave missingHashes as null, so that all hashes are requested
@@ -447,10 +458,9 @@ public class ArbitraryDataFileListManager {
 
             arbitraryTransactionData = (ArbitraryTransactionData) transactionData;
 
-            // Load data file(s)
-            ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromHash(arbitraryTransactionData.getData(), signature);
-            arbitraryDataFile.setMetadataHash(arbitraryTransactionData.getMetadataHash());
-
+//          // Load data file(s)
+//          ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromTransactionData(arbitraryTransactionData);
+//
 //			// Check all hashes exist
 //			for (byte[] hash : hashes) {
 //				//LOGGER.debug("Received hash {}", Base58.encode(hash));
@@ -494,7 +504,7 @@ public class ArbitraryDataFileListManager {
 
         // Forwarding
         if (isRelayRequest && Settings.getInstance().isRelayModeEnabled()) {
-            boolean isBlocked = (arbitraryTransactionData == null || ArbitraryDataStorageManager.getInstance().isNameBlocked(arbitraryTransactionData.getName()));
+            boolean isBlocked = (arbitraryTransactionData == null || ListUtils.isNameBlocked(arbitraryTransactionData.getName()));
             if (!isBlocked) {
                 Peer requestingPeer = request.getB();
                 if (requestingPeer != null) {
@@ -524,6 +534,7 @@ public class ArbitraryDataFileListManager {
                         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);
@@ -580,12 +591,8 @@ public class ArbitraryDataFileListManager {
                 // Check if we're even allowed to serve data for this transaction
                 if (ArbitraryDataStorageManager.getInstance().canStoreData(transactionData)) {
 
-                    byte[] hash = transactionData.getData();
-                    byte[] metadataHash = transactionData.getMetadataHash();
-
                     // Load file(s) and add any that exist to the list of hashes
-                    ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromHash(hash, signature);
-                    arbitraryDataFile.setMetadataHash(metadataHash);
+                    ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromTransactionData(transactionData);
 
                     // If the peer didn't supply a hash list, we need to return all hashes for this transaction
                     if (requestedHashes == null || requestedHashes.isEmpty()) {
@@ -676,7 +683,7 @@ public class ArbitraryDataFileListManager {
         }
 
         // We may need to forward this request on
-        boolean isBlocked = (transactionData == null || ArbitraryDataStorageManager.getInstance().isNameBlocked(transactionData.getName()));
+        boolean isBlocked = (transactionData == null || ListUtils.isNameBlocked(transactionData.getName()));
         if (Settings.getInstance().isRelayModeEnabled() && !isBlocked) {
             // In relay mode - so ask our other peers if they have it
 
@@ -694,9 +701,10 @@ public class ArbitraryDataFileListManager {
 
                     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 : relayGetArbitraryDataFileListMessage);
+                            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

@@ -82,7 +82,7 @@ public class ArbitraryDataFileManager extends Thread {
 
         try {
             // Use a fixed thread pool to execute the arbitrary data file requests
-            int threadCount = 10;
+            int threadCount = 5;
             ExecutorService arbitraryDataFileRequestExecutor = Executors.newFixedThreadPool(threadCount);
             for (int i = 0; i < threadCount; i++) {
                 arbitraryDataFileRequestExecutor.execute(new ArbitraryDataFileRequestThread());
@@ -132,9 +132,7 @@ public class ArbitraryDataFileManager extends Thread {
                                            List<byte[]> hashes) throws DataException {
 
         // Load data file(s)
-        ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromHash(arbitraryTransactionData.getData(), signature);
-        byte[] metadataHash = arbitraryTransactionData.getMetadataHash();
-        arbitraryDataFile.setMetadataHash(metadataHash);
+        ArbitraryDataFile arbitraryDataFile = ArbitraryDataFile.fromTransactionData(arbitraryTransactionData);
         boolean receivedAtLeastOneFile = false;
 
         // Now fetch actual data from this peer
@@ -148,10 +146,10 @@ public class ArbitraryDataFileManager extends Thread {
                 if (!arbitraryDataFileRequests.containsKey(Base58.encode(hash))) {
                     LOGGER.debug("Requesting data file {} from peer {}", hash58, peer);
                     Long startTime = NTP.getTime();
-                    ArbitraryDataFileMessage receivedArbitraryDataFileMessage = fetchArbitraryDataFile(peer, null, signature, hash, null);
+                    ArbitraryDataFile receivedArbitraryDataFile = fetchArbitraryDataFile(peer, null, arbitraryTransactionData, signature, hash, null);
                     Long endTime = NTP.getTime();
-                    if (receivedArbitraryDataFileMessage != null && receivedArbitraryDataFileMessage.getArbitraryDataFile() != null) {
-                        LOGGER.debug("Received data file {} from peer {}. Time taken: {} ms", receivedArbitraryDataFileMessage.getArbitraryDataFile().getHash58(), peer, (endTime-startTime));
+                    if (receivedArbitraryDataFile != null) {
+                        LOGGER.debug("Received data file {} from peer {}. Time taken: {} ms", receivedArbitraryDataFile.getHash58(), peer, (endTime-startTime));
                         receivedAtLeastOneFile = true;
 
                         // Remove this hash from arbitraryDataFileHashResponses now that we have received it
@@ -193,11 +191,11 @@ public class ArbitraryDataFileManager extends Thread {
         return receivedAtLeastOneFile;
     }
 
-    private ArbitraryDataFileMessage fetchArbitraryDataFile(Peer peer, Peer requestingPeer, byte[] signature, byte[] hash, Message originalMessage) throws DataException {
+    private ArbitraryDataFile fetchArbitraryDataFile(Peer peer, Peer requestingPeer, ArbitraryTransactionData arbitraryTransactionData, byte[] signature, byte[] hash, Message originalMessage) throws DataException {
         ArbitraryDataFile existingFile = ArbitraryDataFile.fromHash(hash, signature);
         boolean fileAlreadyExists = existingFile.exists();
         String hash58 = Base58.encode(hash);
-        ArbitraryDataFileMessage arbitraryDataFileMessage;
+        ArbitraryDataFile arbitraryDataFile;
 
         // Fetch the file if it doesn't exist locally
         if (!fileAlreadyExists) {
@@ -227,28 +225,39 @@ public class ArbitraryDataFileManager extends Thread {
             }
 
             ArbitraryDataFileMessage peersArbitraryDataFileMessage = (ArbitraryDataFileMessage) response;
-            arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, peersArbitraryDataFileMessage.getArbitraryDataFile());
+            arbitraryDataFile = peersArbitraryDataFileMessage.getArbitraryDataFile();
         } else {
             LOGGER.debug(String.format("File hash %s already exists, so skipping the request", hash58));
-            arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, existingFile);
+            arbitraryDataFile = existingFile;
+        }
+
+        if (arbitraryDataFile == null) {
+            // We don't have a file, so give up here
+            return null;
         }
 
         // We might want to forward the request to the peer that originally requested it
-        this.handleArbitraryDataFileForwarding(requestingPeer, arbitraryDataFileMessage, originalMessage);
+        this.handleArbitraryDataFileForwarding(requestingPeer, new ArbitraryDataFileMessage(signature, arbitraryDataFile), originalMessage);
 
         boolean isRelayRequest = (requestingPeer != null);
         if (isRelayRequest) {
             if (!fileAlreadyExists) {
                 // File didn't exist locally before the request, and it's a forwarding request, so delete it
                 LOGGER.debug("Deleting file {} because it was needed for forwarding only", Base58.encode(hash));
-                ArbitraryDataFile dataFile = arbitraryDataFileMessage.getArbitraryDataFile();
 
                 // Keep trying to delete the data until it is deleted, or we reach 10 attempts
-                dataFile.delete(10);
+                arbitraryDataFile.delete(10);
             }
         }
 
-        return arbitraryDataFileMessage;
+        // If this is a metadata file then we need to update the cache
+        if (arbitraryTransactionData != null && arbitraryTransactionData.getMetadataHash() != null) {
+            if (Arrays.equals(arbitraryTransactionData.getMetadataHash(), hash)) {
+                ArbitraryDataCacheManager.getInstance().addToUpdateQueue(arbitraryTransactionData);
+            }
+        }
+
+        return arbitraryDataFile;
     }
 
     private void handleFileListRequests(byte[] signature) {
@@ -288,7 +297,7 @@ public class ArbitraryDataFileManager extends Thread {
         // The ID needs to match that of the original request
         message.setId(originalMessage.getId());
 
-        if (!requestingPeer.sendMessage(message)) {
+        if (!requestingPeer.sendMessageWithTimeout(message, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT)) {
             LOGGER.debug("Failed to forward arbitrary data file to peer {}", requestingPeer);
             requestingPeer.disconnect("failed to forward arbitrary data file");
         }
@@ -564,13 +573,16 @@ public class ArbitraryDataFileManager extends Thread {
                 LOGGER.trace("Hash {} exists", hash58);
 
                 // We can serve the file directly as we already have it
+                LOGGER.debug("Sending file {}...", arbitraryDataFile);
                 ArbitraryDataFileMessage arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, arbitraryDataFile);
                 arbitraryDataFileMessage.setId(message.getId());
-                if (!peer.sendMessage(arbitraryDataFileMessage)) {
-                    LOGGER.debug("Couldn't sent file");
+                if (!peer.sendMessageWithTimeout(arbitraryDataFileMessage, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT)) {
+                    LOGGER.debug("Couldn't send file {}", arbitraryDataFile);
                     peer.disconnect("failed to send file");
                 }
-                LOGGER.debug("Sent file {}", arbitraryDataFile);
+                else {
+                    LOGGER.debug("Sent file {}", arbitraryDataFile);
+                }
             }
             else if (relayInfo != null) {
                 LOGGER.debug("We have relay info for hash {}", Base58.encode(hash));
@@ -580,7 +592,9 @@ public class ArbitraryDataFileManager extends Thread {
 
                     // Forward the message to this peer
                     LOGGER.debug("Asking peer {} for hash {}", peerToAsk, hash58);
-                    this.fetchArbitraryDataFile(peerToAsk, peer, signature, hash, message);
+                    // No need to pass arbitraryTransactionData below because this is only used for metadata caching,
+                    // and metadata isn't retained when relaying.
+                    this.fetchArbitraryDataFile(peerToAsk, peer, null, signature, hash, message);
                 }
                 else {
                     LOGGER.debug("Peer {} not found in relay info", peer);
@@ -595,9 +609,10 @@ 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/ArbitraryDataFileRequestThread.java

@@ -114,7 +114,7 @@ public class ArbitraryDataFileRequestThread implements Runnable {
                 return;
             }
 
-            LOGGER.debug("Fetching file {} from peer {} via request thread...", hash58, peer);
+            LOGGER.trace("Fetching file {} from peer {} via request thread...", hash58, peer);
             arbitraryDataFileManager.fetchArbitraryDataFiles(repository, peer, signature, arbitraryTransactionData, Arrays.asList(hash));
 
         } catch (DataException e) {

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

@@ -14,9 +14,9 @@ import org.qortal.arbitrary.ArbitraryDataResource;
 import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.Controller;
+import org.qortal.data.arbitrary.ArbitraryResourceData;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.TransactionData;
-import org.qortal.list.ResourceListManager;
 import org.qortal.network.Network;
 import org.qortal.network.Peer;
 import org.qortal.repository.DataException;
@@ -27,6 +27,7 @@ import org.qortal.transaction.ArbitraryTransaction;
 import org.qortal.transaction.Transaction.TransactionType;
 import org.qortal.utils.ArbitraryTransactionUtils;
 import org.qortal.utils.Base58;
+import org.qortal.utils.ListUtils;
 import org.qortal.utils.NTP;
 
 public class ArbitraryDataManager extends Thread {
@@ -172,7 +173,7 @@ public class ArbitraryDataManager extends Thread {
 
 	private void processNames() throws InterruptedException {
 		// Fetch latest list of followed names
-		List<String> followedNames = ResourceListManager.getInstance().getStringsInList("followedNames");
+		List<String> followedNames = ListUtils.followedNames();
 		if (followedNames == null || followedNames.isEmpty()) {
 			return;
 		}
@@ -398,6 +399,11 @@ public class ArbitraryDataManager extends Thread {
 	// Entrypoint to request new metadata from peers
 	public ArbitraryDataTransactionMetadata fetchMetadata(ArbitraryTransactionData arbitraryTransactionData) {
 
+		if (arbitraryTransactionData.getService() == null) {
+			// Can't fetch metadata without a valid service
+			return null;
+		}
+
 		ArbitraryDataResource resource = new ArbitraryDataResource(
 				arbitraryTransactionData.getName(),
 				ArbitraryDataFile.ResourceIdType.NAME,
@@ -489,7 +495,7 @@ public class ArbitraryDataManager extends Thread {
 	public void invalidateCache(ArbitraryTransactionData arbitraryTransactionData) {
 		String signature58 = Base58.encode(arbitraryTransactionData.getSignature());
 
-		if (arbitraryTransactionData.getName() != null) {
+		if (arbitraryTransactionData.getName() != null && arbitraryTransactionData.getService() != null) {
 			String resourceId = arbitraryTransactionData.getName().toLowerCase();
 			Service service = arbitraryTransactionData.getService();
 			String identifier = arbitraryTransactionData.getIdentifier();
@@ -534,6 +540,17 @@ public class ArbitraryDataManager extends Thread {
 		return true;
 	}
 
+	public void onExpiredArbitraryTransaction(ArbitraryTransactionData arbitraryTransactionData) {
+		if (arbitraryTransactionData.getName() == null) {
+			// No name, so we don't care about this transaction
+			return;
+		}
+
+		// Add to queue for update/deletion
+		ArbitraryDataCacheManager.getInstance().addToUpdateQueue(arbitraryTransactionData);
+
+	}
+
 	public int getPowDifficulty() {
 		return this.powDifficulty;
 	}

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

@@ -5,15 +5,11 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 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.settings.Settings;
 import org.qortal.transaction.Transaction;
-import org.qortal.utils.ArbitraryTransactionUtils;
-import org.qortal.utils.Base58;
-import org.qortal.utils.FilesystemUtils;
-import org.qortal.utils.NTP;
+import org.qortal.utils.*;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
@@ -48,7 +44,6 @@ public class ArbitraryDataStorageManager extends Thread {
     private List<ArbitraryTransactionData> hostedTransactions;
 
     private String searchQuery;
-    private List<ArbitraryTransactionData> searchResultsTransactions;
 
     private static final long DIRECTORY_SIZE_CHECK_INTERVAL = 10 * 60 * 1000L; // 10 minutes
 
@@ -62,6 +57,8 @@ public class ArbitraryDataStorageManager extends Thread {
      * This must be higher than STORAGE_FULL_THRESHOLD in order to avoid a fetch/delete loop. */
     public static final double DELETION_THRESHOLD = 0.98f; // 98%
 
+    private static final long PER_NAME_STORAGE_MULTIPLIER = 4L;
+
     public ArbitraryDataStorageManager() {
     }
 
@@ -136,11 +133,11 @@ public class ArbitraryDataStorageManager extends Thread {
             case ALL:
             case VIEWED:
                 // If the policy includes viewed data, we can host it as long as it's not blocked
-                return !this.isNameBlocked(name);
+                return !ListUtils.isNameBlocked(name);
 
             case FOLLOWED:
                 // If the policy is for followed data only, we have to be following it
-                return this.isFollowingName(name);
+                return ListUtils.isFollowingName(name);
 
                 // For NONE or all else, we shouldn't host this data
             case NONE:
@@ -189,14 +186,14 @@ public class ArbitraryDataStorageManager extends Thread {
         }
 
         // Never fetch data from blocked names, even if they are followed
-        if (this.isNameBlocked(name)) {
+        if (ListUtils.isNameBlocked(name)) {
             return false;
         }
 
         switch (Settings.getInstance().getStoragePolicy()) {
             case FOLLOWED:
             case FOLLOWED_OR_VIEWED:
-                return this.isFollowingName(name);
+                return ListUtils.isFollowingName(name);
                 
             case ALL:
                 return true;
@@ -236,7 +233,7 @@ public class ArbitraryDataStorageManager extends Thread {
      * @return boolean - whether the resource is blocked or not
      */
     public boolean isBlocked(ArbitraryTransactionData arbitraryTransactionData) {
-        return isNameBlocked(arbitraryTransactionData.getName());
+        return ListUtils.isNameBlocked(arbitraryTransactionData.getName());
     }
 
     private boolean isDataTypeAllowed(ArbitraryTransactionData arbitraryTransactionData) {
@@ -254,22 +251,6 @@ public class ArbitraryDataStorageManager extends Thread {
         return true;
     }
 
-    public boolean isNameBlocked(String name) {
-        return ResourceListManager.getInstance().listContains("blockedNames", name, false);
-    }
-
-    private boolean isFollowingName(String name) {
-        return ResourceListManager.getInstance().listContains("followedNames", name, false);
-    }
-
-    public List<String> followedNames() {
-        return ResourceListManager.getInstance().getStringsInList("followedNames");
-    }
-
-    private int followedNamesCount() {
-        return ResourceListManager.getInstance().getItemCountForList("followedNames");
-    }
-
 
     public List<ArbitraryTransactionData> loadAllHostedTransactions(Repository repository) {
         
@@ -344,11 +325,6 @@ public class ArbitraryDataStorageManager extends Thread {
      */
 
     public List<ArbitraryTransactionData> searchHostedTransactions(Repository repository, String query, Integer limit, Integer offset) {
-        // Load from results cache if we can (results that exists for the same query), to avoid disk reads
-        if (this.searchResultsTransactions != null && this.searchQuery.equals(query.toLowerCase())) {
-            return ArbitraryTransactionUtils.limitOffsetTransactions(this.searchResultsTransactions, limit, offset);
-        }
-
         // Using cache if we can, to avoid disk reads
         if (this.hostedTransactions == null) {
             this.hostedTransactions = this.loadAllHostedTransactions(repository);
@@ -376,10 +352,7 @@ public class ArbitraryDataStorageManager extends Thread {
         // Sort by newest first
         searchResultsList.sort(Comparator.comparingLong(ArbitraryTransactionData::getTimestamp).reversed());
 
-        // Update cache
-        this.searchResultsTransactions = searchResultsList;
-
-        return ArbitraryTransactionUtils.limitOffsetTransactions(this.searchResultsTransactions, limit, offset);
+        return ArbitraryTransactionUtils.limitOffsetTransactions(searchResultsList, limit, offset);
     }
 
     /**
@@ -517,12 +490,17 @@ public class ArbitraryDataStorageManager extends Thread {
             return false;
         }
 
+        if (Settings.getInstance().getStoragePolicy() == StoragePolicy.ALL) {
+            // Using storage policy ALL, so don't limit anything per name
+            return true;
+        }
+
         if (name == null) {
             // This transaction doesn't have a name, so fall back to total space limitations
             return true;
         }
 
-        int followedNamesCount = this.followedNamesCount();
+        int followedNamesCount = ListUtils.followedNamesCount();
         if (followedNamesCount == 0) {
             // Not following any names, so we have space
             return true;
@@ -552,14 +530,16 @@ public class ArbitraryDataStorageManager extends Thread {
     }
 
     public long storageCapacityPerName(double threshold) {
-        int followedNamesCount = this.followedNamesCount();
+        int followedNamesCount = ListUtils.followedNamesCount();
         if (followedNamesCount == 0) {
             // Not following any names, so we have the total space available
             return this.getStorageCapacityIncludingThreshold(threshold);
         }
 
         double maxStorageCapacity = (double)this.storageCapacity * threshold;
-        long maxStoragePerName = (long)(maxStorageCapacity / (double)followedNamesCount);
+
+        // Some names won't need/use much space, so give all names a 4x multiplier to compensate
+        long maxStoragePerName = (long)(maxStorageCapacity / (double)followedNamesCount) * PER_NAME_STORAGE_MULTIPLIER;
 
         return maxStoragePerName;
     }

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

@@ -16,14 +16,14 @@ import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 import org.qortal.settings.Settings;
 import org.qortal.utils.Base58;
+import org.qortal.utils.ListUtils;
 import org.qortal.utils.NTP;
 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 {
 
@@ -102,7 +102,14 @@ public class ArbitraryMetadataManager {
                 if (metadataFile.exists()) {
                     // Use local copy
                     ArbitraryDataTransactionMetadata transactionMetadata = new ArbitraryDataTransactionMetadata(metadataFile.getFilePath());
-                    transactionMetadata.read();
+                    try {
+                        transactionMetadata.read();
+                    } catch (DataException e) {
+                        // Invalid file, so delete it
+                        LOGGER.info("Deleting invalid metadata file due to exception: {}", e.getMessage());
+                        transactionMetadata.delete();
+                        return null;
+                    }
                     return transactionMetadata;
                 }
             }
@@ -313,41 +320,46 @@ public class ArbitraryMetadataManager {
             return;
         }
 
-        // Update requests map to reflect that we've received all chunks
+        // Update requests map to reflect that we've received this metadata
         Triple<String, Peer, Long> newEntry = new Triple<>(null, null, request.getC());
         arbitraryMetadataRequests.put(message.getId(), newEntry);
 
-        ArbitraryTransactionData arbitraryTransactionData = null;
-
-        // Forwarding
-        if (isRelayRequest && Settings.getInstance().isRelayModeEnabled()) {
-
-            // Get transaction info
-            try (final Repository repository = RepositoryManager.getRepository()) {
-                TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
-                if (!(transactionData instanceof ArbitraryTransactionData))
-                    return;
-                arbitraryTransactionData = (ArbitraryTransactionData) transactionData;
-            } catch (DataException e) {
-                LOGGER.error(String.format("Repository issue while finding arbitrary transaction metadata for peer %s", peer), e);
+        // Get transaction info
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
+            if (!(transactionData instanceof ArbitraryTransactionData)) {
+                return;
             }
+            ArbitraryTransactionData arbitraryTransactionData = (ArbitraryTransactionData) transactionData;
 
-            // Check if the name is blocked
-            boolean isBlocked = (arbitraryTransactionData == null || ArbitraryDataStorageManager.getInstance().isNameBlocked(arbitraryTransactionData.getName()));
-            if (!isBlocked) {
-                Peer requestingPeer = request.getB();
-                if (requestingPeer != null) {
+            // Forwarding
+            if (isRelayRequest && Settings.getInstance().isRelayModeEnabled()) {
 
-                    ArbitraryMetadataMessage forwardArbitraryMetadataMessage = new ArbitraryMetadataMessage(signature, arbitraryMetadataMessage.getArbitraryMetadataFile());
-                    forwardArbitraryMetadataMessage.setId(arbitraryMetadataMessage.getId());
+                // Check if the name is blocked
+                boolean isBlocked = (arbitraryTransactionData == null || ListUtils.isNameBlocked(arbitraryTransactionData.getName()));
+                if (!isBlocked) {
+                    Peer requestingPeer = request.getB();
+                    if (requestingPeer != null) {
 
-                    // Forward to requesting peer
-                    LOGGER.debug("Forwarding metadata to requesting peer: {}", requestingPeer);
-                    if (!requestingPeer.sendMessage(forwardArbitraryMetadataMessage)) {
-                        requestingPeer.disconnect("failed to forward arbitrary metadata");
+                        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(forwardArbitraryMetadataMessage)) {
+                            requestingPeer.disconnect("failed to forward arbitrary metadata");
+                        }
                     }
                 }
             }
+
+            // Add to resource queue to update arbitrary resource caches
+            if (arbitraryTransactionData != null) {
+                ArbitraryDataCacheManager.getInstance().addToUpdateQueue(arbitraryTransactionData);
+            }
+
+        } catch (DataException e) {
+            LOGGER.error(String.format("Repository issue while saving arbitrary transaction metadata from peer %s", peer), e);
         }
     }
 
@@ -421,7 +433,7 @@ public class ArbitraryMetadataManager {
         }
 
         // We may need to forward this request on
-        boolean isBlocked = (transactionData == null || ArbitraryDataStorageManager.getInstance().isNameBlocked(transactionData.getName()));
+        boolean isBlocked = (transactionData == null || ListUtils.isNameBlocked(transactionData.getName()));
         if (Settings.getInstance().isRelayModeEnabled() && !isBlocked) {
             // In relay mode - so ask our other peers if they have it
 
@@ -435,12 +447,13 @@ public class ArbitraryMetadataManager {
                     // 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 : relayGetArbitraryMetadataMessage);
+                            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

@@ -39,9 +39,11 @@ public class AtStatesPruner implements Runnable {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			int pruneStartHeight = repository.getATRepository().getAtPruneHeight();
+			int maxLatestAtStatesHeight = PruneManager.getMaxHeightForLatestAtStates(repository);
 
 			repository.discardChanges();
-			repository.getATRepository().rebuildLatestAtStates();
+			repository.getATRepository().rebuildLatestAtStates(maxLatestAtStatesHeight);
+			repository.saveChanges();
 
 			while (!Controller.isStopping()) {
 				repository.discardChanges();
@@ -91,7 +93,8 @@ public class AtStatesPruner implements Runnable {
 					if (upperPrunableHeight > upperBatchHeight) {
 						pruneStartHeight = upperBatchHeight;
 						repository.getATRepository().setAtPruneHeight(pruneStartHeight);
-						repository.getATRepository().rebuildLatestAtStates();
+						maxLatestAtStatesHeight = PruneManager.getMaxHeightForLatestAtStates(repository);
+						repository.getATRepository().rebuildLatestAtStates(maxLatestAtStatesHeight);
 						repository.saveChanges();
 
 						final int finalPruneStartHeight = pruneStartHeight;