Merge branch 'development' of https://github.com/0xProject/0x-monorepo into feature/sra/add-sra-package

2018-08-07 13:52:53 -07:00
parent 57a4429123 8199e87943
commit 0a616ad3b8
73 changed files with 2437 additions and 1575 deletions
--- a/README.md
+++ b/README.md
@@ -82,10 +82,12 @@ We strongly recommend that the community help us make improvements and determine

 ### Install dependencies

-If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:
+Make sure you are using Yarn v1.6. To install using brew:

-```bash
-yarn config set workspaces-experimental true
+```
+brew unlink yarn
+brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/76215230de5f7f7bee2cfcdd7185cf49d949862d/Formula/yarn.rb
+brew switch yarn 1.6.0_1
 ```

 Then install dependencies
--- a/packages/contract-wrappers/CHANGELOG.json
+++ b/packages/contract-wrappers/CHANGELOG.json
@@ -1,4 +1,17 @@
 [
+    {
+        "version": "1.0.1-rc.3",
+        "changes": [
+            {
+                "note": "Add ForwarderWrapper",
+                "pr": 934
+            },
+            {
+                "note": "Optimize orders in ForwarderWrapper",
+                "pr": 936
+            }
+        ]
+    },
    {
        "version": "1.0.1-rc.2",
        "changes": [
--- a/packages/contract-wrappers/package.json
+++ b/packages/contract-wrappers/package.json
@@ -14,7 +14,7 @@
        "watch_without_deps": "yarn pre_build && tsc -w",
        "build": "yarn pre_build && tsc && copyfiles -u 3 './lib/src/monorepo_scripts/**/*' ./scripts",
        "pre_build": "run-s update_artifacts_v2_beta update_artifacts_v2 generate_contract_wrappers copy_artifacts",
-        "generate_contract_wrappers": "abi-gen --abis 'src/artifacts/@(Exchange|DummyERC20Token|DummyERC721Token|ZRXToken|ERC20Token|ERC721Token|WETH9|ERC20Proxy|ERC721Proxy).json' --template ../contract_templates/contract.handlebars --partials '../contract_templates/partials/**/*.handlebars' --output src/contract_wrappers/generated --backend ethers",
+        "generate_contract_wrappers": "abi-gen --abis 'src/artifacts/@(Exchange|DummyERC20Token|DummyERC721Token|ZRXToken|ERC20Token|ERC721Token|WETH9|ERC20Proxy|ERC721Proxy|Forwarder).json' --template ../contract_templates/contract.handlebars --partials '../contract_templates/partials/**/*.handlebars' --output src/contract_wrappers/generated --backend ethers",
        "lint": "tslint --project . --exclude **/src/contract_wrappers/**/* --exclude **/lib/**/*",
        "test:circleci": "run-s test:coverage",
        "test": "yarn run_mocha",
@@ -29,7 +29,7 @@
        "manual:postpublish": "yarn build; node ./scripts/postpublish.js"
    },
    "config": {
-        "contracts_v2_beta": "Exchange ERC20Proxy ERC20Token ERC721Proxy ERC721Token WETH9 ZRXToken",
+        "contracts_v2_beta": "Exchange ERC20Proxy ERC20Token ERC721Proxy ERC721Token WETH9 ZRXToken Forwarder",
        "contracts_v2": "DummyERC20Token DummyERC721Token"
    },
    "repository": {
--- a/packages/contract-wrappers/src/artifacts.ts
+++ b/packages/contract-wrappers/src/artifacts.ts
@@ -7,6 +7,7 @@ import * as ERC20Token from './artifacts/ERC20Token.json';
 import * as ERC721Proxy from './artifacts/ERC721Proxy.json';
 import * as ERC721Token from './artifacts/ERC721Token.json';
 import * as Exchange from './artifacts/Exchange.json';
+import * as Forwarder from './artifacts/Forwarder.json';
 import * as EtherToken from './artifacts/WETH9.json';
 import * as ZRXToken from './artifacts/ZRXToken.json';

@@ -20,4 +21,5 @@ export const artifacts = {
    EtherToken: (EtherToken as any) as ContractArtifact,
    ERC20Proxy: (ERC20Proxy as any) as ContractArtifact,
    ERC721Proxy: (ERC721Proxy as any) as ContractArtifact,
+    Forwarder: (Forwarder as any) as ContractArtifact,
 };
--- a/packages/contract-wrappers/src/contract_wrappers.ts
+++ b/packages/contract-wrappers/src/contract_wrappers.ts
@@ -11,6 +11,7 @@ import { ERC721ProxyWrapper } from './contract_wrappers/erc721_proxy_wrapper';
 import { ERC721TokenWrapper } from './contract_wrappers/erc721_token_wrapper';
 import { EtherTokenWrapper } from './contract_wrappers/ether_token_wrapper';
 import { ExchangeWrapper } from './contract_wrappers/exchange_wrapper';
+import { ForwarderWrapper } from './contract_wrappers/forwarder_wrapper';
 import { ContractWrappersConfigSchema } from './schemas/contract_wrappers_config_schema';
 import { contractWrappersPrivateNetworkConfigSchema } from './schemas/contract_wrappers_private_network_config_schema';
 import { contractWrappersPublicNetworkConfigSchema } from './schemas/contract_wrappers_public_network_config_schema';
@@ -47,6 +48,11 @@ export class ContractWrappers {
     * erc721Proxy smart contract.
     */
    public erc721Proxy: ERC721ProxyWrapper;
+    /**
+     * An instance of the ForwarderWrapper class containing methods for interacting with any Forwarder smart contract.
+     */
+    public forwarder: ForwarderWrapper;
+
    private _web3Wrapper: Web3Wrapper;
    /**
     * Instantiates a new ContractWrappers instance.
@@ -104,6 +110,12 @@ export class ContractWrappers {
            config.zrxContractAddress,
            blockPollingIntervalMs,
        );
+        this.forwarder = new ForwarderWrapper(
+            this._web3Wrapper,
+            config.networkId,
+            config.forwarderContractAddress,
+            config.zrxContractAddress,
+        );
    }
    /**
     * Sets a new web3 provider for 0x.js. Updating the provider will stop all
--- a/packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts
@@ -869,15 +869,35 @@ export class ExchangeWrapper extends ContractWrapper {
     */
    @decorators.asyncZeroExErrorHandler
    public async getOrderInfoAsync(order: Order | SignedOrder, methodOpts: MethodOpts = {}): Promise<OrderInfo> {
+        assert.doesConformToSchema('order', order, schemas.orderSchema);
        if (!_.isUndefined(methodOpts)) {
            assert.doesConformToSchema('methodOpts', methodOpts, methodOptsSchema);
        }
        const exchangeInstance = await this._getExchangeContractAsync();
-
        const txData = {};
        const orderInfo = await exchangeInstance.getOrderInfo.callAsync(order, txData, methodOpts.defaultBlock);
        return orderInfo;
    }
+    /**
+     * Get order info for multiple orders
+     * @param orders         Orders
+     * @param methodOpts    Optional arguments this method accepts.
+     * @returns Array of Order infos
+     */
+    @decorators.asyncZeroExErrorHandler
+    public async getOrdersInfoAsync(
+        orders: Array<Order | SignedOrder>,
+        methodOpts: MethodOpts = {},
+    ): Promise<OrderInfo[]> {
+        assert.doesConformToSchema('orders', orders, schemas.ordersSchema);
+        if (!_.isUndefined(methodOpts)) {
+            assert.doesConformToSchema('methodOpts', methodOpts, methodOptsSchema);
+        }
+        const exchangeInstance = await this._getExchangeContractAsync();
+        const txData = {};
+        const ordersInfo = await exchangeInstance.getOrdersInfo.callAsync(orders, txData, methodOpts.defaultBlock);
+        return ordersInfo;
+    }
    /**
     * Cancel a given order.
     * @param   order           An object that conforms to the Order or SignedOrder interface. The order you would like to cancel.
--- a/packages/contract-wrappers/src/contract_wrappers/forwarder_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/forwarder_wrapper.ts
@@ -0,0 +1,220 @@
+import { schemas } from '@0xproject/json-schemas';
+import { AssetProxyId, SignedOrder } from '@0xproject/types';
+import { BigNumber } from '@0xproject/utils';
+import { Web3Wrapper } from '@0xproject/web3-wrapper';
+import { ContractAbi } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { artifacts } from '../artifacts';
+import { orderTxOptsSchema } from '../schemas/order_tx_opts_schema';
+import { txOptsSchema } from '../schemas/tx_opts_schema';
+import { TransactionOpts } from '../types';
+import { assert } from '../utils/assert';
+import { calldataOptimizationUtils } from '../utils/calldata_optimization_utils';
+import { constants } from '../utils/constants';
+
+import { ContractWrapper } from './contract_wrapper';
+import { ForwarderContract } from './generated/forwarder';
+
+/**
+ * This class includes the functionality related to interacting with the Forwarder contract.
+ */
+export class ForwarderWrapper extends ContractWrapper {
+    public abi: ContractAbi = artifacts.Forwarder.compilerOutput.abi;
+    private _forwarderContractIfExists?: ForwarderContract;
+    private _contractAddressIfExists?: string;
+    private _zrxContractAddressIfExists?: string;
+    constructor(
+        web3Wrapper: Web3Wrapper,
+        networkId: number,
+        contractAddressIfExists?: string,
+        zrxContractAddressIfExists?: string,
+    ) {
+        super(web3Wrapper, networkId);
+        this._contractAddressIfExists = contractAddressIfExists;
+        this._zrxContractAddressIfExists = zrxContractAddressIfExists;
+    }
+    /**
+     * Purchases as much of orders' makerAssets as possible by selling up to 95% of transaction's ETH value.
+     * Any ZRX required to pay fees for primary orders will automatically be purchased by this contract.
+     * 5% of ETH value is reserved for paying fees to order feeRecipients (in ZRX) and forwarding contract feeRecipient (in ETH).
+     * Any ETH not spent will be refunded to sender.
+     * @param   signedOrders         An array of objects that conform to the SignedOrder interface. All orders must specify the same makerAsset.
+     *                               All orders must specify WETH as the takerAsset
+     * @param   takerAddress         The user Ethereum address who would like to fill this order. Must be available via the supplied
+     *                               Provider provided at instantiation.
+     * @param   ethAmount            The amount of eth to send with the transaction (in wei).
+     * @param   signedFeeOrders      An array of objects that conform to the SignedOrder interface. All orders must specify ZRX as makerAsset and WETH as takerAsset.
+     *                               Used to purchase ZRX for primary order fees.
+     * @param   feePercentage        The percentage of WETH sold that will payed as fee to forwarding contract feeRecipient.
+     *                               Defaults to 0.
+     * @param   feeRecipientAddress  The address that will receive ETH when signedFeeOrders are filled.
+     * @param   txOpts               Transaction parameters.
+     * @return  Transaction hash.
+     */
+    public async marketSellOrdersWithEthAsync(
+        signedOrders: SignedOrder[],
+        takerAddress: string,
+        ethAmount: BigNumber,
+        signedFeeOrders: SignedOrder[] = [],
+        feePercentage: BigNumber = constants.ZERO_AMOUNT,
+        feeRecipientAddress: string = constants.NULL_ADDRESS,
+        txOpts: TransactionOpts = {},
+    ): Promise<string> {
+        // type assertions
+        assert.doesConformToSchema('signedOrders', signedOrders, schemas.signedOrdersSchema);
+        await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
+        assert.isBigNumber('ethAmount', ethAmount);
+        assert.doesConformToSchema('signedFeeOrders', signedFeeOrders, schemas.signedOrdersSchema);
+        assert.isBigNumber('feePercentage', feePercentage);
+        assert.isETHAddressHex('feeRecipientAddress', feeRecipientAddress);
+        assert.doesConformToSchema('txOpts', txOpts, txOptsSchema);
+        // other assertions
+        assert.ordersCanBeUsedForForwarderContract(signedOrders, this.getEtherTokenAddress());
+        assert.feeOrdersCanBeUsedForForwarderContract(
+            signedFeeOrders,
+            this.getZRXTokenAddress(),
+            this.getEtherTokenAddress(),
+        );
+        // lowercase input addresses
+        const normalizedTakerAddress = takerAddress.toLowerCase();
+        const normalizedFeeRecipientAddress = feeRecipientAddress.toLowerCase();
+        // optimize orders
+        const optimizedMarketOrders = calldataOptimizationUtils.optimizeForwarderOrders(signedOrders);
+        const optimizedFeeOrders = calldataOptimizationUtils.optimizeForwarderFeeOrders(signedFeeOrders);
+        // send transaction
+        const forwarderContractInstance = await this._getForwarderContractAsync();
+        const txHash = await forwarderContractInstance.marketSellOrdersWithEth.sendTransactionAsync(
+            optimizedMarketOrders,
+            _.map(optimizedMarketOrders, order => order.signature),
+            optimizedFeeOrders,
+            _.map(optimizedFeeOrders, order => order.signature),
+            feePercentage,
+            feeRecipientAddress,
+            {
+                value: ethAmount,
+                from: normalizedTakerAddress,
+                gas: txOpts.gasLimit,
+                gasPrice: txOpts.gasPrice,
+            },
+        );
+        return txHash;
+    }
+    /**
+     * Attempt to purchase makerAssetFillAmount of makerAsset by selling ethAmount provided with transaction.
+     * Any ZRX required to pay fees for primary orders will automatically be purchased by the contract.
+     * Any ETH not spent will be refunded to sender.
+     * @param   signedOrders         An array of objects that conform to the SignedOrder interface. All orders must specify the same makerAsset.
+     *                               All orders must specify WETH as the takerAsset
+     * @param   makerAssetFillAmount The amount of the order (in taker asset baseUnits) that you wish to fill.
+     * @param   takerAddress         The user Ethereum address who would like to fill this order. Must be available via the supplied
+     *                               Provider provided at instantiation.
+     * @param   ethAmount            The amount of eth to send with the transaction (in wei).
+     * @param   signedFeeOrders      An array of objects that conform to the SignedOrder interface. All orders must specify ZRX as makerAsset and WETH as takerAsset.
+     *                               Used to purchase ZRX for primary order fees.
+     * @param   feePercentage        The percentage of WETH sold that will payed as fee to forwarding contract feeRecipient.
+     *                               Defaults to 0.
+     * @param   feeRecipientAddress  The address that will receive ETH when signedFeeOrders are filled.
+     * @param   txOpts               Transaction parameters.
+     * @return  Transaction hash.
+     */
+    public async marketBuyOrdersWithEthAsync(
+        signedOrders: SignedOrder[],
+        makerAssetFillAmount: BigNumber,
+        takerAddress: string,
+        ethAmount: BigNumber,
+        signedFeeOrders: SignedOrder[] = [],
+        feePercentage: BigNumber = constants.ZERO_AMOUNT,
+        feeRecipientAddress: string = constants.NULL_ADDRESS,
+        txOpts: TransactionOpts = {},
+    ): Promise<string> {
+        // type assertions
+        assert.doesConformToSchema('signedOrders', signedOrders, schemas.signedOrdersSchema);
+        assert.isBigNumber('makerAssetFillAmount', makerAssetFillAmount);
+        await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
+        assert.isBigNumber('ethAmount', ethAmount);
+        assert.doesConformToSchema('signedFeeOrders', signedFeeOrders, schemas.signedOrdersSchema);
+        assert.isBigNumber('feePercentage', feePercentage);
+        assert.isETHAddressHex('feeRecipientAddress', feeRecipientAddress);
+        assert.doesConformToSchema('txOpts', txOpts, txOptsSchema);
+        // other assertions
+        assert.ordersCanBeUsedForForwarderContract(signedOrders, this.getEtherTokenAddress());
+        assert.feeOrdersCanBeUsedForForwarderContract(
+            signedFeeOrders,
+            this.getZRXTokenAddress(),
+            this.getEtherTokenAddress(),
+        );
+        // lowercase input addresses
+        const normalizedTakerAddress = takerAddress.toLowerCase();
+        const normalizedFeeRecipientAddress = feeRecipientAddress.toLowerCase();
+        // optimize orders
+        const optimizedMarketOrders = calldataOptimizationUtils.optimizeForwarderOrders(signedOrders);
+        const optimizedFeeOrders = calldataOptimizationUtils.optimizeForwarderFeeOrders(signedFeeOrders);
+        // send transaction
+        const forwarderContractInstance = await this._getForwarderContractAsync();
+        const txHash = await forwarderContractInstance.marketBuyOrdersWithEth.sendTransactionAsync(
+            optimizedMarketOrders,
+            makerAssetFillAmount,
+            _.map(optimizedMarketOrders, order => order.signature),
+            optimizedFeeOrders,
+            _.map(optimizedFeeOrders, order => order.signature),
+            feePercentage,
+            feeRecipientAddress,
+            {
+                value: ethAmount,
+                from: normalizedTakerAddress,
+                gas: txOpts.gasLimit,
+                gasPrice: txOpts.gasPrice,
+            },
+        );
+        return txHash;
+    }
+    /**
+     * Retrieves the Ethereum address of the Forwarder contract deployed on the network
+     * that the user-passed web3 provider is connected to.
+     * @returns The Ethereum address of the Forwarder contract being used.
+     */
+    public getContractAddress(): string {
+        const contractAddress = this._getContractAddress(artifacts.Forwarder, this._contractAddressIfExists);
+        return contractAddress;
+    }
+    /**
+     * Returns the ZRX token address used by the forwarder contract.
+     * @return Address of ZRX token
+     */
+    public getZRXTokenAddress(): string {
+        const contractAddress = this._getContractAddress(artifacts.ZRXToken, this._zrxContractAddressIfExists);
+        return contractAddress;
+    }
+    /**
+     * Returns the Ether token address used by the forwarder contract.
+     * @return Address of Ether token
+     */
+    public getEtherTokenAddress(): string {
+        const contractAddress = this._getContractAddress(artifacts.EtherToken);
+        return contractAddress;
+    }
+    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
+    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
+    // tslint:disable-next-line:no-unused-variable
+    private _invalidateContractInstance(): void {
+        delete this._forwarderContractIfExists;
+    }
+    private async _getForwarderContractAsync(): Promise<ForwarderContract> {
+        if (!_.isUndefined(this._forwarderContractIfExists)) {
+            return this._forwarderContractIfExists;
+        }
+        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
+            artifacts.Forwarder,
+            this._contractAddressIfExists,
+        );
+        const contractInstance = new ForwarderContract(
+            abi,
+            address,
+            this._web3Wrapper.getProvider(),
+            this._web3Wrapper.getContractDefaults(),
+        );
+        this._forwarderContractIfExists = contractInstance;
+        return this._forwarderContractIfExists;
+    }
+}
--- a/packages/contract-wrappers/src/index.ts
+++ b/packages/contract-wrappers/src/index.ts
@@ -5,6 +5,7 @@ export { EtherTokenWrapper } from './contract_wrappers/ether_token_wrapper';
 export { ExchangeWrapper } from './contract_wrappers/exchange_wrapper';
 export { ERC20ProxyWrapper } from './contract_wrappers/erc20_proxy_wrapper';
 export { ERC721ProxyWrapper } from './contract_wrappers/erc721_proxy_wrapper';
+export { ForwarderWrapper } from './contract_wrappers/forwarder_wrapper';

 export {
    ContractWrappersError,
--- a/packages/contract-wrappers/src/types.ts
+++ b/packages/contract-wrappers/src/types.ts
@@ -109,6 +109,7 @@ export type SyncMethod = (...args: any[]) => any;
 * zrxContractAddress: The address of the ZRX contract to use
 * erc20ProxyContractAddress: The address of the erc20 token transfer proxy contract to use
 * erc721ProxyContractAddress: The address of the erc721 token transfer proxy contract to use
+ * forwarderContractAddress: The address of the forwarder contract to use
 * orderWatcherConfig: All the configs related to the orderWatcher
 * blockPollingIntervalMs: The interval to use for block polling in event watching methods (defaults to 1000)
 */
@@ -119,6 +120,7 @@ export interface ContractWrappersConfig {
    zrxContractAddress?: string;
    erc20ProxyContractAddress?: string;
    erc721ProxyContractAddress?: string;
+    forwarderContractAddress?: string;
    blockPollingIntervalMs?: number;
 }

@@ -172,13 +174,13 @@ export enum TransferType {
 export type OnOrderStateChangeCallback = (err: Error | null, orderState?: OrderState) => void;

 export interface OrderInfo {
-    orderStatus: number;
+    orderStatus: OrderStatus;
    orderHash: string;
    orderTakerAssetFilledAmount: BigNumber;
 }

 export enum OrderStatus {
-    INVALID,
+    INVALID = 0,
    INVALID_MAKER_ASSET_AMOUNT,
    INVALID_TAKER_ASSET_AMOUNT,
    FILLABLE,
--- a/packages/contract-wrappers/src/utils/assert.ts
+++ b/packages/contract-wrappers/src/utils/assert.ts
@@ -1,11 +1,14 @@
 import { assert as sharedAssert } from '@0xproject/assert';
 // HACK: We need those two unused imports because they're actually used by sharedAssert which gets injected here
 import { Schema } from '@0xproject/json-schemas'; // tslint:disable-line:no-unused-variable
-import { isValidSignatureAsync } from '@0xproject/order-utils';
-import { ECSignature } from '@0xproject/types'; // tslint:disable-line:no-unused-variable
+import { assetDataUtils, isValidSignatureAsync } from '@0xproject/order-utils';
+import { ECSignature, Order } from '@0xproject/types'; // tslint:disable-line:no-unused-variable
 import { BigNumber } from '@0xproject/utils'; // tslint:disable-line:no-unused-variable
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { Provider } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { constants } from './constants';

 export const assert = {
    ...sharedAssert,
@@ -16,12 +19,12 @@ export const assert = {
        signerAddress: string,
    ): Promise<void> {
        const isValid = await isValidSignatureAsync(provider, orderHash, signature, signerAddress);
-        this.assert(isValid, `Expected order with hash '${orderHash}' to have a valid signature`);
+        sharedAssert.assert(isValid, `Expected order with hash '${orderHash}' to have a valid signature`);
    },
    isValidSubscriptionToken(variableName: string, subscriptionToken: string): void {
        const uuidRegex = new RegExp('^[a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}$');
        const isValid = uuidRegex.test(subscriptionToken);
-        this.assert(isValid, `Expected ${variableName} to be a valid subscription token`);
+        sharedAssert.assert(isValid, `Expected ${variableName} to be a valid subscription token`);
    },
    async isSenderAddressAsync(
        variableName: string,
@@ -35,4 +38,53 @@ export const assert = {
            `Specified ${variableName} ${senderAddressHex} isn't available through the supplied web3 provider`,
        );
    },
+    ordersCanBeUsedForForwarderContract(orders: Order[], etherTokenAddress: string): void {
+        sharedAssert.assert(!_.isEmpty(orders), 'Expected at least 1 signed order. Found no orders');
+        assert.ordersHaveAtMostOneUniqueValueForProperty(orders, 'makerAssetData');
+        assert.allTakerAssetDatasAreErc20Token(orders, etherTokenAddress);
+        assert.allTakerAddressesAreNull(orders);
+    },
+    feeOrdersCanBeUsedForForwarderContract(orders: Order[], zrxTokenAddress: string, etherTokenAddress: string): void {
+        if (!_.isEmpty(orders)) {
+            assert.allMakerAssetDatasAreErc20Token(orders, zrxTokenAddress);
+            assert.allTakerAssetDatasAreErc20Token(orders, etherTokenAddress);
+        }
+    },
+    allTakerAddressesAreNull(orders: Order[]): void {
+        assert.ordersHaveAtMostOneUniqueValueForProperty(orders, 'takerAddress', constants.NULL_ADDRESS);
+    },
+    allMakerAssetDatasAreErc20Token(orders: Order[], tokenAddress: string): void {
+        assert.ordersHaveAtMostOneUniqueValueForProperty(
+            orders,
+            'makerAssetData',
+            assetDataUtils.encodeERC20AssetData(tokenAddress),
+        );
+    },
+    allTakerAssetDatasAreErc20Token(orders: Order[], tokenAddress: string): void {
+        assert.ordersHaveAtMostOneUniqueValueForProperty(
+            orders,
+            'takerAssetData',
+            assetDataUtils.encodeERC20AssetData(tokenAddress),
+        );
+    },
+    /*
+     * Asserts that all the orders have the same value for the provided propertyName
+     * If the value parameter is provided, this asserts that all orders have the prope
+    */
+    ordersHaveAtMostOneUniqueValueForProperty(orders: Order[], propertyName: string, value?: any): void {
+        const allValues = _.map(orders, order => _.get(order, propertyName));
+        sharedAssert.hasAtMostOneUniqueValue(
+            allValues,
+            `Expected all orders to have the same ${propertyName} field. Found the following ${propertyName} values: ${JSON.stringify(
+                allValues,
+            )}`,
+        );
+        if (!_.isUndefined(value)) {
+            const firstValue = _.head(allValues);
+            sharedAssert.assert(
+                firstValue === value,
+                `Expected all orders to have a ${propertyName} field with value: ${value}. Found: ${firstValue}`,
+            );
+        }
+    },
 };
--- a/packages/contract-wrappers/src/utils/calldata_optimization_utils.ts
+++ b/packages/contract-wrappers/src/utils/calldata_optimization_utils.ts
@@ -0,0 +1,44 @@
+import { SignedOrder } from '@0xproject/types';
+import * as _ from 'lodash';
+
+import { constants } from './constants';
+
+export const calldataOptimizationUtils = {
+    /**
+     * Takes an array of orders and outputs an array of equivalent orders where all takerAssetData are '0x' and
+     * all makerAssetData are '0x' except for that of the first order, which retains its original value
+     * @param   orders         An array of SignedOrder objects
+     * @returns optimized orders
+     */
+    optimizeForwarderOrders(orders: SignedOrder[]): SignedOrder[] {
+        const optimizedOrders = _.map(orders, (order, index) =>
+            transformOrder(order, {
+                makerAssetData: index === 0 ? order.makerAssetData : constants.NULL_BYTES,
+                takerAssetData: constants.NULL_BYTES,
+            }),
+        );
+        return optimizedOrders;
+    },
+    /**
+     * Takes an array of orders and outputs an array of equivalent orders where all takerAssetData are '0x' and
+     * all makerAssetData are '0x'
+     * @param   orders         An array of SignedOrder objects
+     * @returns optimized orders
+     */
+    optimizeForwarderFeeOrders(orders: SignedOrder[]): SignedOrder[] {
+        const optimizedOrders = _.map(orders, (order, index) =>
+            transformOrder(order, {
+                makerAssetData: constants.NULL_BYTES,
+                takerAssetData: constants.NULL_BYTES,
+            }),
+        );
+        return optimizedOrders;
+    },
+};
+
+const transformOrder = (order: SignedOrder, partialOrder: Partial<SignedOrder>) => {
+    return {
+        ...order,
+        ...partialOrder,
+    };
+};
--- a/packages/contract-wrappers/src/utils/constants.ts
+++ b/packages/contract-wrappers/src/utils/constants.ts
@@ -2,6 +2,7 @@ import { BigNumber } from '@0xproject/utils';

 export const constants = {
    NULL_ADDRESS: '0x0000000000000000000000000000000000000000',
+    NULL_BYTES: '0x',
    TESTRPC_NETWORK_ID: 50,
    INVALID_JUMP_PATTERN: 'invalid JUMP at',
    REVERT: 'revert',
@@ -10,4 +11,5 @@ export const constants = {
    // tslint:disable-next-line:custom-no-magic-numbers
    UNLIMITED_ALLOWANCE_IN_BASE_UNITS: new BigNumber(2).pow(256).minus(1),
    DEFAULT_BLOCK_POLLING_INTERVAL: 1000,
+    ZERO_AMOUNT: new BigNumber(0),
 };
--- a/packages/contract-wrappers/test/calldata_optimization_utils_test.ts
+++ b/packages/contract-wrappers/test/calldata_optimization_utils_test.ts
@@ -0,0 +1,60 @@
+import { orderFactory } from '@0xproject/order-utils';
+import * as chai from 'chai';
+import * as _ from 'lodash';
+import 'mocha';
+
+import { assert } from '../src/utils/assert';
+import { calldataOptimizationUtils } from '../src/utils/calldata_optimization_utils';
+import { constants } from '../src/utils/constants';
+
+import { chaiSetup } from './utils/chai_setup';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+// utility for generating a set of order objects with mostly NULL values
+// except for a specified makerAssetData and takerAssetData
+const FAKE_ORDERS_COUNT = 5;
+const generateFakeOrders = (makerAssetData: string, takerAssetData: string) =>
+    _.map(_.range(FAKE_ORDERS_COUNT), index => {
+        const order = orderFactory.createOrder(
+            constants.NULL_ADDRESS,
+            constants.ZERO_AMOUNT,
+            makerAssetData,
+            constants.ZERO_AMOUNT,
+            takerAssetData,
+            constants.NULL_ADDRESS,
+        );
+        return {
+            ...order,
+            signature: 'dummy signature',
+        };
+    });
+
+describe('calldataOptimizationUtils', () => {
+    const fakeMakerAssetData = 'fakeMakerAssetData';
+    const fakeTakerAssetData = 'fakeTakerAssetData';
+    const orders = generateFakeOrders(fakeMakerAssetData, fakeTakerAssetData);
+    describe('#optimizeForwarderOrders', () => {
+        it('should make makerAssetData `0x` unless first order', () => {
+            const optimizedOrders = calldataOptimizationUtils.optimizeForwarderOrders(orders);
+            expect(optimizedOrders[0].makerAssetData).to.equal(fakeMakerAssetData);
+            const ordersWithoutHead = _.slice(optimizedOrders, 1);
+            _.forEach(ordersWithoutHead, order => expect(order.makerAssetData).to.equal(constants.NULL_BYTES));
+        });
+        it('should make all takerAssetData `0x`', () => {
+            const optimizedOrders = calldataOptimizationUtils.optimizeForwarderOrders(orders);
+            _.forEach(optimizedOrders, order => expect(order.takerAssetData).to.equal(constants.NULL_BYTES));
+        });
+    });
+    describe('#optimizeForwarderFeeOrders', () => {
+        it('should make all makerAssetData `0x`', () => {
+            const optimizedOrders = calldataOptimizationUtils.optimizeForwarderFeeOrders(orders);
+            _.forEach(optimizedOrders, order => expect(order.makerAssetData).to.equal(constants.NULL_BYTES));
+        });
+        it('should make all takerAssetData `0x`', () => {
+            const optimizedOrders = calldataOptimizationUtils.optimizeForwarderFeeOrders(orders);
+            _.forEach(optimizedOrders, order => expect(order.takerAssetData).to.equal(constants.NULL_BYTES));
+        });
+    });
+});
--- a/packages/contract-wrappers/test/exchange_wrapper_test.ts
+++ b/packages/contract-wrappers/test/exchange_wrapper_test.ts
@@ -277,6 +277,15 @@ describe('ExchangeWrapper', () => {
            expect(orderInfo.orderHash).to.be.equal(orderHash);
        });
    });
+    describe('#getOrdersInfoAsync', () => {
+        it('should get the orders info', async () => {
+            const ordersInfo = await contractWrappers.exchange.getOrdersInfoAsync([signedOrder, anotherSignedOrder]);
+            const orderHash = orderHashUtils.getOrderHashHex(signedOrder);
+            expect(ordersInfo[0].orderHash).to.be.equal(orderHash);
+            const anotherOrderHash = orderHashUtils.getOrderHashHex(anotherSignedOrder);
+            expect(ordersInfo[1].orderHash).to.be.equal(anotherOrderHash);
+        });
+    });
    describe('#isValidSignature', () => {
        it('should check if the signature is valid', async () => {
            const orderHash = orderHashUtils.getOrderHashHex(signedOrder);
@@ -295,7 +304,7 @@ describe('ExchangeWrapper', () => {
        });
    });
    describe('#isAllowedValidatorAsync', () => {
-        it('should check if the validator is alllowed', async () => {
+        it('should check if the validator is allowed', async () => {
            const signerAddress = makerAddress;
            const validatorAddress = constants.NULL_ADDRESS;
            const isAllowed = await contractWrappers.exchange.isAllowedValidatorAsync(signerAddress, validatorAddress);
--- a/packages/contract-wrappers/test/forwarder_wrapper_test.ts
+++ b/packages/contract-wrappers/test/forwarder_wrapper_test.ts
@@ -0,0 +1,130 @@
+import { BlockchainLifecycle, callbackErrorReporter } from '@0xproject/dev-utils';
+import { FillScenarios } from '@0xproject/fill-scenarios';
+import { assetDataUtils, orderHashUtils } from '@0xproject/order-utils';
+import { DoneCallback, SignedOrder } from '@0xproject/types';
+import { BigNumber } from '@0xproject/utils';
+import * as chai from 'chai';
+import { BlockParamLiteral } from 'ethereum-types';
+import 'mocha';
+
+import {
+    ContractWrappers,
+    DecodedLogEvent,
+    ExchangeCancelEventArgs,
+    ExchangeEvents,
+    ExchangeFillEventArgs,
+    OrderStatus,
+} from '../src';
+
+import { chaiSetup } from './utils/chai_setup';
+import { constants } from './utils/constants';
+import { tokenUtils } from './utils/token_utils';
+import { provider, web3Wrapper } from './utils/web3_wrapper';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+
+describe('ForwarderWrapper', () => {
+    const contractWrappersConfig = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+        blockPollingIntervalMs: 0,
+    };
+    const fillableAmount = new BigNumber(5);
+    const takerTokenFillAmount = new BigNumber(5);
+    let contractWrappers: ContractWrappers;
+    let fillScenarios: FillScenarios;
+    let forwarderContractAddress: string;
+    let exchangeContractAddress: string;
+    let zrxTokenAddress: string;
+    let userAddresses: string[];
+    let coinbase: string;
+    let makerAddress: string;
+    let takerAddress: string;
+    let feeRecipient: string;
+    let anotherMakerAddress: string;
+    let makerTokenAddress: string;
+    let takerTokenAddress: string;
+    let makerAssetData: string;
+    let takerAssetData: string;
+    let signedOrder: SignedOrder;
+    let anotherSignedOrder: SignedOrder;
+    before(async () => {
+        await blockchainLifecycle.startAsync();
+        contractWrappers = new ContractWrappers(provider, contractWrappersConfig);
+        forwarderContractAddress = contractWrappers.forwarder.getContractAddress();
+        exchangeContractAddress = contractWrappers.exchange.getContractAddress();
+        userAddresses = await web3Wrapper.getAvailableAddressesAsync();
+        zrxTokenAddress = tokenUtils.getProtocolTokenAddress();
+        fillScenarios = new FillScenarios(
+            provider,
+            userAddresses,
+            zrxTokenAddress,
+            exchangeContractAddress,
+            contractWrappers.erc20Proxy.getContractAddress(),
+            contractWrappers.erc721Proxy.getContractAddress(),
+        );
+        [coinbase, makerAddress, takerAddress, feeRecipient, anotherMakerAddress] = userAddresses;
+        [makerTokenAddress] = tokenUtils.getDummyERC20TokenAddresses();
+        takerTokenAddress = tokenUtils.getWethTokenAddress();
+        [makerAssetData, takerAssetData] = [
+            assetDataUtils.encodeERC20AssetData(makerTokenAddress),
+            assetDataUtils.encodeERC20AssetData(takerTokenAddress),
+        ];
+        signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+            makerAssetData,
+            takerAssetData,
+            makerAddress,
+            constants.NULL_ADDRESS,
+            fillableAmount,
+        );
+        anotherSignedOrder = await fillScenarios.createFillableSignedOrderAsync(
+            makerAssetData,
+            takerAssetData,
+            makerAddress,
+            constants.NULL_ADDRESS,
+            fillableAmount,
+        );
+    });
+    after(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('#marketBuyOrdersWithEthAsync', () => {
+        it('should market buy orders with eth', async () => {
+            const signedOrders = [signedOrder, anotherSignedOrder];
+            const makerAssetFillAmount = signedOrder.makerAssetAmount.plus(anotherSignedOrder.makerAssetAmount);
+            const txHash = await contractWrappers.forwarder.marketBuyOrdersWithEthAsync(
+                signedOrders,
+                makerAssetFillAmount,
+                takerAddress,
+                makerAssetFillAmount,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(txHash, constants.AWAIT_TRANSACTION_MINED_MS);
+            const ordersInfo = await contractWrappers.exchange.getOrdersInfoAsync([signedOrder, anotherSignedOrder]);
+            expect(ordersInfo[0].orderStatus).to.be.equal(OrderStatus.FULLY_FILLED);
+            expect(ordersInfo[1].orderStatus).to.be.equal(OrderStatus.FULLY_FILLED);
+        });
+    });
+    describe('#marketSellOrdersWithEthAsync', () => {
+        it('should market sell orders with eth', async () => {
+            const signedOrders = [signedOrder, anotherSignedOrder];
+            const makerAssetFillAmount = signedOrder.makerAssetAmount.plus(anotherSignedOrder.makerAssetAmount);
+            const txHash = await contractWrappers.forwarder.marketSellOrdersWithEthAsync(
+                signedOrders,
+                takerAddress,
+                makerAssetFillAmount,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(txHash, constants.AWAIT_TRANSACTION_MINED_MS);
+            const ordersInfo = await contractWrappers.exchange.getOrdersInfoAsync([signedOrder, anotherSignedOrder]);
+            expect(ordersInfo[0].orderStatus).to.be.equal(OrderStatus.FULLY_FILLED);
+            expect(ordersInfo[1].orderStatus).to.be.equal(OrderStatus.FILLABLE);
+            expect(ordersInfo[1].orderTakerAssetFilledAmount).to.be.bignumber.equal(new BigNumber(4)); // only 95% of ETH is sold
+        });
+    });
+});
--- a/packages/contracts/compiler.json
+++ b/packages/contracts/compiler.json
@@ -42,12 +42,13 @@
        "TestConstants",
        "TestLibBytes",
        "TestLibs",
+        "TestExchangeInternals",
        "TestSignatureValidator",
        "TokenRegistry",
        "Validator",
        "Wallet",
-        "Whitelist",
        "WETH9",
+        "Whitelist",
        "ZRXToken"
    ]
 }
--- a/packages/contracts/package.json
+++ b/packages/contracts/package.json
@@ -33,7 +33,7 @@
        "lint-contracts": "solhint src/2.0.0/**/**/**/**/*.sol"
    },
    "config": {
-        "abis": "../migrations/artifacts/2.0.0/@(AssetProxyOwner|DummyERC20Token|DummyERC721Receiver|DummyERC721Token|ERC20Proxy|ERC721Proxy|Forwarder|Exchange|ExchangeWrapper|IAssetData|IAssetProxy|MixinAuthorizable|MultiSigWallet|MultiSigWalletWithTimeLock|TestAssetProxyOwner|TestAssetProxyDispatcher|TestConstants|TestLibBytes|TestLibs|TestSignatureValidator|Validator|Wallet|TokenRegistry|Whitelist|WETH9|ZRXToken).json"
+        "abis": "../migrations/artifacts/2.0.0/@(AssetProxyOwner|DummyERC20Token|DummyERC721Receiver|DummyERC721Token|ERC20Proxy|ERC721Proxy|Forwarder|Exchange|ExchangeWrapper|IAssetData|IAssetProxy|MixinAuthorizable|MultiSigWallet|MultiSigWalletWithTimeLock|TestAssetProxyOwner|TestAssetProxyDispatcher|TestConstants|TestExchangeInternals|TestLibBytes|TestLibs|TestSignatureValidator|Validator|Wallet|TokenRegistry|Whitelist|WETH9|ZRXToken).json"
    },
    "repository": {
        "type": "git",
@@ -79,11 +79,13 @@
        "@0xproject/typescript-typings": "^1.0.3",
        "@0xproject/utils": "^1.0.4",
        "@0xproject/web3-wrapper": "^1.1.2",
+        "@types/js-combinatorics": "^0.5.29",
        "bn.js": "^4.11.8",
        "ethereum-types": "^1.0.3",
        "ethereumjs-abi": "0.6.5",
        "ethereumjs-util": "^5.1.1",
        "ethers": "3.0.22",
+        "js-combinatorics": "^0.5.3",
        "lodash": "^4.17.4"
    }
 }
--- a/packages/contracts/src/2.0.0/protocol/Exchange/MixinExchangeCore.sol
+++ b/packages/contracts/src/2.0.0/protocol/Exchange/MixinExchangeCore.sol
@@ -207,7 +207,6 @@ contract MixinExchangeCore is
    /// @param order that was filled.
    /// @param takerAddress Address of taker who filled the order.
    /// @param orderTakerAssetFilledAmount Amount of order already filled.
-    /// @return fillResults Amounts filled and fees paid by maker and taker.
    function updateFilledState(
        Order memory order,
        address takerAddress,
--- a/packages/contracts/src/2.0.0/test/TestExchangeInternals/TestExchangeInternals.sol
+++ b/packages/contracts/src/2.0.0/test/TestExchangeInternals/TestExchangeInternals.sol
@@ -0,0 +1,120 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  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.
+
+*/
+
+pragma solidity 0.4.24;
+pragma experimental ABIEncoderV2;
+
+import "../../protocol/Exchange/Exchange.sol";
+
+
+contract TestExchangeInternals is
+    Exchange
+{
+    constructor ()
+        public
+        Exchange("")
+    {}
+
+    /// @dev Adds properties of both FillResults instances.
+    ///      Modifies the first FillResults instance specified.
+    ///      Note that this function has been modified from the original
+    //       internal version to return the FillResults.
+    /// @param totalFillResults Fill results instance that will be added onto.
+    /// @param singleFillResults Fill results instance that will be added to totalFillResults.
+    /// @return newTotalFillResults The result of adding singleFillResults to totalFilResults.
+    function publicAddFillResults(FillResults memory totalFillResults, FillResults memory singleFillResults)
+        public
+        pure
+        returns (FillResults memory)
+    {
+        addFillResults(totalFillResults, singleFillResults);
+        return totalFillResults;
+    }
+
+    /// @dev Calculates amounts filled and fees paid by maker and taker.
+    /// @param order to be filled.
+    /// @param takerAssetFilledAmount Amount of takerAsset that will be filled.
+    /// @return fillResults Amounts filled and fees paid by maker and taker.
+    function publicCalculateFillResults(
+        Order memory order,
+        uint256 takerAssetFilledAmount
+    )
+        public
+        pure
+        returns (FillResults memory fillResults)
+    {
+        return calculateFillResults(order, takerAssetFilledAmount);
+    }
+
+    /// @dev Calculates partial value given a numerator and denominator.
+    /// @param numerator Numerator.
+    /// @param denominator Denominator.
+    /// @param target Value to calculate partial of.
+    /// @return Partial value of target.
+    function publicGetPartialAmount(
+        uint256 numerator,
+        uint256 denominator,
+        uint256 target
+    )
+        public
+        pure
+        returns (uint256 partialAmount)
+    {
+        return getPartialAmount(numerator, denominator, target);
+    }
+
+    /// @dev Checks if rounding error > 0.1%.
+    /// @param numerator Numerator.
+    /// @param denominator Denominator.
+    /// @param target Value to multiply with numerator/denominator.
+    /// @return Rounding error is present.
+    function publicIsRoundingError(
+        uint256 numerator,
+        uint256 denominator,
+        uint256 target
+    )
+        public
+        pure
+        returns (bool isError)
+    {
+        return isRoundingError(numerator, denominator, target);
+    }
+ 
+    /// @dev Updates state with results of a fill order.
+    /// @param order that was filled.
+    /// @param takerAddress Address of taker who filled the order.
+    /// @param orderTakerAssetFilledAmount Amount of order already filled.
+    /// @return fillResults Amounts filled and fees paid by maker and taker.
+    function publicUpdateFilledState(
+        Order memory order,
+        address takerAddress,
+        bytes32 orderHash,
+        uint256 orderTakerAssetFilledAmount,
+        FillResults memory fillResults
+    )
+        public
+    {
+        updateFilledState(
+            order,
+            takerAddress,
+            orderHash,
+            orderTakerAssetFilledAmount,
+            fillResults
+        );
+    }
+}
--- a/packages/contracts/test/exchange/fill_order.ts
+++ b/packages/contracts/test/exchange/fill_order.ts
@@ -2,7 +2,10 @@ import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import * as _ from 'lodash';

 import { chaiSetup } from '../utils/chai_setup';
-import { CoreCombinatorialUtils, coreCombinatorialUtilsFactoryAsync } from '../utils/core_combinatorial_utils';
+import {
+    FillOrderCombinatorialUtils,
+    fillOrderCombinatorialUtilsFactoryAsync,
+} from '../utils/fill_order_combinatorial_utils';
 import {
    AllowanceAmountScenario,
    AssetDataScenario,
@@ -47,11 +50,11 @@ const defaultFillScenario = {
 };

 describe('FillOrder Tests', () => {
-    let coreCombinatorialUtils: CoreCombinatorialUtils;
+    let fillOrderCombinatorialUtils: FillOrderCombinatorialUtils;

    before(async () => {
        await blockchainLifecycle.startAsync();
-        coreCombinatorialUtils = await coreCombinatorialUtilsFactoryAsync(web3Wrapper, txDefaults);
+        fillOrderCombinatorialUtils = await fillOrderCombinatorialUtilsFactoryAsync(web3Wrapper, txDefaults);
    });
    after(async () => {
        await blockchainLifecycle.revertAsync();
@@ -67,19 +70,19 @@ describe('FillOrder Tests', () => {
            _.forEach(fillScenarios, fillScenario => {
                const description = `Combinatorial OrderFill: ${JSON.stringify(fillScenario)}`;
                it(description, async () => {
-                    await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+                    await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
                });
            });
        };

-        const allFillScenarios = CoreCombinatorialUtils.generateFillOrderCombinations();
+        const allFillScenarios = FillOrderCombinatorialUtils.generateFillOrderCombinations();
        describe('Combinatorially generated fills orders', () => test(allFillScenarios));

        it('should transfer the correct amounts when makerAssetAmount === takerAssetAmount', async () => {
            const fillScenario = {
                ...defaultFillScenario,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
        it('should transfer the correct amounts when makerAssetAmount > takerAssetAmount', async () => {
            const fillScenario = {
@@ -89,7 +92,7 @@ describe('FillOrder Tests', () => {
                    takerAssetAmountScenario: OrderAssetAmountScenario.Small,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
        it('should transfer the correct amounts when makerAssetAmount < takerAssetAmount', async () => {
            const fillScenario = {
@@ -99,7 +102,7 @@ describe('FillOrder Tests', () => {
                    makerAssetAmountScenario: OrderAssetAmountScenario.Small,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
        it('should transfer the correct amounts when taker is specified and order is claimed by taker', async () => {
            const fillScenario = {
@@ -109,14 +112,14 @@ describe('FillOrder Tests', () => {
                    takerScenario: TakerScenario.CorrectlySpecified,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
        it('should fill remaining value if takerAssetFillAmount > remaining takerAssetAmount', async () => {
            const fillScenario = {
                ...defaultFillScenario,
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.GreaterThanRemainingFillableTakerAssetAmount,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
        it('should throw when taker is specified and order is claimed by other', async () => {
            const fillScenario = {
@@ -126,7 +129,7 @@ describe('FillOrder Tests', () => {
                    takerScenario: TakerScenario.IncorrectlySpecified,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if makerAssetAmount is 0', async () => {
@@ -138,7 +141,7 @@ describe('FillOrder Tests', () => {
                },
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.GreaterThanRemainingFillableTakerAssetAmount,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if takerAssetAmount is 0', async () => {
@@ -150,7 +153,7 @@ describe('FillOrder Tests', () => {
                },
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.GreaterThanRemainingFillableTakerAssetAmount,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if takerAssetFillAmount is 0', async () => {
@@ -158,7 +161,7 @@ describe('FillOrder Tests', () => {
                ...defaultFillScenario,
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.Zero,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if an order is expired', async () => {
@@ -169,7 +172,7 @@ describe('FillOrder Tests', () => {
                    expirationTimeSecondsScenario: ExpirationTimeSecondsScenario.InPast,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if maker erc20Balances are too low to fill order', async () => {
@@ -180,7 +183,7 @@ describe('FillOrder Tests', () => {
                    traderAssetBalance: BalanceAmountScenario.TooLow,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if taker erc20Balances are too low to fill order', async () => {
@@ -191,7 +194,7 @@ describe('FillOrder Tests', () => {
                    traderAssetBalance: BalanceAmountScenario.TooLow,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if maker allowances are too low to fill order', async () => {
@@ -202,7 +205,7 @@ describe('FillOrder Tests', () => {
                    traderAssetAllowance: AllowanceAmountScenario.TooLow,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should throw if taker allowances are too low to fill order', async () => {
@@ -213,7 +216,7 @@ describe('FillOrder Tests', () => {
                    traderAssetAllowance: AllowanceAmountScenario.TooLow,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
    });

@@ -228,7 +231,7 @@ describe('FillOrder Tests', () => {
                },
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.ExactlyRemainingFillableTakerAssetAmount,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should successfully fill order when makerAsset is ERC721 and takerAsset is ERC20', async () => {
@@ -241,7 +244,7 @@ describe('FillOrder Tests', () => {
                },
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.ExactlyRemainingFillableTakerAssetAmount,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario, true);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario, true);
        });

        it('should successfully fill order when makerAsset is ERC20 and takerAsset is ERC721', async () => {
@@ -254,7 +257,7 @@ describe('FillOrder Tests', () => {
                },
                takerAssetFillAmountScenario: TakerAssetFillAmountScenario.ExactlyRemainingFillableTakerAssetAmount,
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should successfully fill order when makerAsset is ERC721 and approveAll is set for it', async () => {
@@ -271,7 +274,7 @@ describe('FillOrder Tests', () => {
                    traderAssetAllowance: AllowanceAmountScenario.Unlimited,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });

        it('should successfully fill order when makerAsset and takerAsset are ERC721 and approveAll is set for them', async () => {
@@ -292,7 +295,7 @@ describe('FillOrder Tests', () => {
                    traderAssetAllowance: AllowanceAmountScenario.Unlimited,
                },
            };
-            await coreCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
+            await fillOrderCombinatorialUtils.testFillOrderScenarioAsync(provider, fillScenario);
        });
    });
 });
--- a/packages/contracts/test/exchange/internal.ts
+++ b/packages/contracts/test/exchange/internal.ts
@@ -0,0 +1,305 @@
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
+import { Order, RevertReason, SignedOrder } from '@0xproject/types';
+import { BigNumber } from '@0xproject/utils';
+import * as _ from 'lodash';
+
+import { TestExchangeInternalsContract } from '../../generated_contract_wrappers/test_exchange_internals';
+import { artifacts } from '../utils/artifacts';
+import {
+    getInvalidOpcodeErrorMessageForCallAsync,
+    getRevertReasonOrErrorMessageForSendTransactionAsync,
+} from '../utils/assertions';
+import { chaiSetup } from '../utils/chai_setup';
+import { bytes32Values, testCombinatoriallyWithReferenceFuncAsync, uint256Values } from '../utils/combinatorial_utils';
+import { constants } from '../utils/constants';
+import { FillResults } from '../utils/types';
+import { provider, txDefaults, web3Wrapper } from '../utils/web3_wrapper';
+
+chaiSetup.configure();
+const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+
+const MAX_UINT256 = new BigNumber(2).pow(256).minus(1);
+
+const emptyOrder: Order = {
+    senderAddress: constants.NULL_ADDRESS,
+    makerAddress: constants.NULL_ADDRESS,
+    takerAddress: constants.NULL_ADDRESS,
+    makerFee: new BigNumber(0),
+    takerFee: new BigNumber(0),
+    makerAssetAmount: new BigNumber(0),
+    takerAssetAmount: new BigNumber(0),
+    makerAssetData: '0x',
+    takerAssetData: '0x',
+    salt: new BigNumber(0),
+    exchangeAddress: constants.NULL_ADDRESS,
+    feeRecipientAddress: constants.NULL_ADDRESS,
+    expirationTimeSeconds: new BigNumber(0),
+};
+
+const emptySignedOrder: SignedOrder = {
+    ...emptyOrder,
+    signature: '',
+};
+
+const overflowErrorForCall = new Error(RevertReason.Uint256Overflow);
+
+async function referenceGetPartialAmountAsync(
+    numerator: BigNumber,
+    denominator: BigNumber,
+    target: BigNumber,
+): Promise<BigNumber> {
+    const invalidOpcodeErrorForCall = new Error(await getInvalidOpcodeErrorMessageForCallAsync());
+    const product = numerator.mul(target);
+    if (product.greaterThan(MAX_UINT256)) {
+        throw overflowErrorForCall;
+    }
+    if (denominator.eq(0)) {
+        throw invalidOpcodeErrorForCall;
+    }
+    return product.dividedToIntegerBy(denominator);
+}
+
+describe('Exchange core internal functions', () => {
+    let testExchange: TestExchangeInternalsContract;
+    let invalidOpcodeErrorForCall: Error | undefined;
+    let overflowErrorForSendTransaction: Error | undefined;
+
+    before(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    after(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    before(async () => {
+        testExchange = await TestExchangeInternalsContract.deployFrom0xArtifactAsync(
+            artifacts.TestExchangeInternals,
+            provider,
+            txDefaults,
+        );
+        overflowErrorForSendTransaction = new Error(
+            await getRevertReasonOrErrorMessageForSendTransactionAsync(RevertReason.Uint256Overflow),
+        );
+        invalidOpcodeErrorForCall = new Error(await getInvalidOpcodeErrorMessageForCallAsync());
+    });
+    // Note(albrow): Don't forget to add beforeEach and afterEach calls to reset
+    // the blockchain state for any tests which modify it!
+
+    describe('addFillResults', async () => {
+        function makeFillResults(value: BigNumber): FillResults {
+            return {
+                makerAssetFilledAmount: value,
+                takerAssetFilledAmount: value,
+                makerFeePaid: value,
+                takerFeePaid: value,
+            };
+        }
+        async function referenceAddFillResultsAsync(
+            totalValue: BigNumber,
+            singleValue: BigNumber,
+        ): Promise<FillResults> {
+            // Note(albrow): Here, each of totalFillResults and
+            // singleFillResults will consist of fields with the same values.
+            // This should be safe because none of the fields in a given
+            // FillResults are ever used together in a mathemetical operation.
+            // They are only used with the corresponding field from *the other*
+            // FillResults, which are different.
+            const totalFillResults = makeFillResults(totalValue);
+            const singleFillResults = makeFillResults(singleValue);
+            // HACK(albrow): _.mergeWith mutates the first argument! To
+            // workaround this we use _.cloneDeep.
+            return _.mergeWith(
+                _.cloneDeep(totalFillResults),
+                singleFillResults,
+                (totalVal: BigNumber, singleVal: BigNumber) => {
+                    const newTotal = totalVal.add(singleVal);
+                    if (newTotal.greaterThan(MAX_UINT256)) {
+                        throw overflowErrorForCall;
+                    }
+                    return newTotal;
+                },
+            );
+        }
+        async function testAddFillResultsAsync(totalValue: BigNumber, singleValue: BigNumber): Promise<FillResults> {
+            const totalFillResults = makeFillResults(totalValue);
+            const singleFillResults = makeFillResults(singleValue);
+            return testExchange.publicAddFillResults.callAsync(totalFillResults, singleFillResults);
+        }
+        await testCombinatoriallyWithReferenceFuncAsync(
+            'addFillResults',
+            referenceAddFillResultsAsync,
+            testAddFillResultsAsync,
+            [uint256Values, uint256Values],
+        );
+    });
+
+    describe('calculateFillResults', async () => {
+        function makeOrder(
+            makerAssetAmount: BigNumber,
+            takerAssetAmount: BigNumber,
+            makerFee: BigNumber,
+            takerFee: BigNumber,
+        ): Order {
+            return {
+                ...emptyOrder,
+                makerAssetAmount,
+                takerAssetAmount,
+                makerFee,
+                takerFee,
+            };
+        }
+        async function referenceCalculateFillResultsAsync(
+            orderTakerAssetAmount: BigNumber,
+            takerAssetFilledAmount: BigNumber,
+            otherAmount: BigNumber,
+        ): Promise<FillResults> {
+            // Note(albrow): Here we are re-using the same value (otherAmount)
+            // for order.makerAssetAmount, order.makerFee, and order.takerFee.
+            // This should be safe because they are never used with each other
+            // in any mathematical operation in either the reference TypeScript
+            // implementation or the Solidity implementation of
+            // calculateFillResults.
+            return {
+                makerAssetFilledAmount: await referenceGetPartialAmountAsync(
+                    takerAssetFilledAmount,
+                    orderTakerAssetAmount,
+                    otherAmount,
+                ),
+                takerAssetFilledAmount,
+                makerFeePaid: await referenceGetPartialAmountAsync(
+                    takerAssetFilledAmount,
+                    orderTakerAssetAmount,
+                    otherAmount,
+                ),
+                takerFeePaid: await referenceGetPartialAmountAsync(
+                    takerAssetFilledAmount,
+                    orderTakerAssetAmount,
+                    otherAmount,
+                ),
+            };
+        }
+        async function testCalculateFillResultsAsync(
+            orderTakerAssetAmount: BigNumber,
+            takerAssetFilledAmount: BigNumber,
+            otherAmount: BigNumber,
+        ): Promise<FillResults> {
+            const order = makeOrder(otherAmount, orderTakerAssetAmount, otherAmount, otherAmount);
+            return testExchange.publicCalculateFillResults.callAsync(order, takerAssetFilledAmount);
+        }
+        await testCombinatoriallyWithReferenceFuncAsync(
+            'calculateFillResults',
+            referenceCalculateFillResultsAsync,
+            testCalculateFillResultsAsync,
+            [uint256Values, uint256Values, uint256Values],
+        );
+    });
+
+    describe('getPartialAmount', async () => {
+        async function testGetPartialAmountAsync(
+            numerator: BigNumber,
+            denominator: BigNumber,
+            target: BigNumber,
+        ): Promise<BigNumber> {
+            return testExchange.publicGetPartialAmount.callAsync(numerator, denominator, target);
+        }
+        await testCombinatoriallyWithReferenceFuncAsync(
+            'getPartialAmount',
+            referenceGetPartialAmountAsync,
+            testGetPartialAmountAsync,
+            [uint256Values, uint256Values, uint256Values],
+        );
+    });
+
+    describe('isRoundingError', async () => {
+        async function referenceIsRoundingErrorAsync(
+            numerator: BigNumber,
+            denominator: BigNumber,
+            target: BigNumber,
+        ): Promise<boolean> {
+            const product = numerator.mul(target);
+            if (denominator.eq(0)) {
+                throw invalidOpcodeErrorForCall;
+            }
+            const remainder = product.mod(denominator);
+            if (remainder.eq(0)) {
+                return false;
+            }
+            if (product.greaterThan(MAX_UINT256)) {
+                throw overflowErrorForCall;
+            }
+            if (product.eq(0)) {
+                throw invalidOpcodeErrorForCall;
+            }
+            const remainderTimes1000000 = remainder.mul('1000000');
+            if (remainderTimes1000000.greaterThan(MAX_UINT256)) {
+                throw overflowErrorForCall;
+            }
+            const errPercentageTimes1000000 = remainderTimes1000000.dividedToIntegerBy(product);
+            return errPercentageTimes1000000.greaterThan('1000');
+        }
+        async function testIsRoundingErrorAsync(
+            numerator: BigNumber,
+            denominator: BigNumber,
+            target: BigNumber,
+        ): Promise<boolean> {
+            return testExchange.publicIsRoundingError.callAsync(numerator, denominator, target);
+        }
+        await testCombinatoriallyWithReferenceFuncAsync(
+            'isRoundingError',
+            referenceIsRoundingErrorAsync,
+            testIsRoundingErrorAsync,
+            [uint256Values, uint256Values, uint256Values],
+        );
+    });
+
+    describe('updateFilledState', async () => {
+        // Note(albrow): Since updateFilledState modifies the state by calling
+        // sendTransaction, we must reset the state after each test.
+        beforeEach(async () => {
+            await blockchainLifecycle.startAsync();
+        });
+        afterEach(async () => {
+            await blockchainLifecycle.revertAsync();
+        });
+        async function referenceUpdateFilledStateAsync(
+            takerAssetFilledAmount: BigNumber,
+            orderTakerAssetFilledAmount: BigNumber,
+            // tslint:disable-next-line:no-unused-variable
+            orderHash: string,
+        ): Promise<BigNumber> {
+            const totalFilledAmount = takerAssetFilledAmount.add(orderTakerAssetFilledAmount);
+            if (totalFilledAmount.greaterThan(MAX_UINT256)) {
+                throw overflowErrorForSendTransaction;
+            }
+            return totalFilledAmount;
+        }
+        async function testUpdateFilledStateAsync(
+            takerAssetFilledAmount: BigNumber,
+            orderTakerAssetFilledAmount: BigNumber,
+            orderHash: string,
+        ): Promise<BigNumber> {
+            const fillResults = {
+                makerAssetFilledAmount: new BigNumber(0),
+                takerAssetFilledAmount,
+                makerFeePaid: new BigNumber(0),
+                takerFeePaid: new BigNumber(0),
+            };
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await testExchange.publicUpdateFilledState.sendTransactionAsync(
+                    emptySignedOrder,
+                    constants.NULL_ADDRESS,
+                    orderHash,
+                    orderTakerAssetFilledAmount,
+                    fillResults,
+                ),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            return testExchange.filled.callAsync(orderHash);
+        }
+        await testCombinatoriallyWithReferenceFuncAsync(
+            'updateFilledState',
+            referenceUpdateFilledStateAsync,
+            testUpdateFilledStateAsync,
+            [uint256Values, uint256Values, bytes32Values],
+        );
+    });
+});
--- a/packages/contracts/test/exchange/libs.ts
+++ b/packages/contracts/test/exchange/libs.ts
@@ -67,6 +67,35 @@ describe('Exchange libs', () => {
            });
        });
    });
+    // Note(albrow): These tests are designed to be supplemental to the
+    // combinatorial tests in test/exchange/internal. They test specific edge
+    // cases that are not covered by the combinatorial tests.
+    describe('LibMath', () => {
+        it('should return false if there is a rounding error of 0.1%', async () => {
+            const numerator = new BigNumber(20);
+            const denominator = new BigNumber(999);
+            const target = new BigNumber(50);
+            // rounding error = ((20*50/999) - floor(20*50/999)) / (20*50/999) = 0.1%
+            const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
+            expect(isRoundingError).to.be.false();
+        });
+        it('should return false if there is a rounding of 0.09%', async () => {
+            const numerator = new BigNumber(20);
+            const denominator = new BigNumber(9991);
+            const target = new BigNumber(500);
+            // rounding error = ((20*500/9991) - floor(20*500/9991)) / (20*500/9991) = 0.09%
+            const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
+            expect(isRoundingError).to.be.false();
+        });
+        it('should return true if there is a rounding error of 0.11%', async () => {
+            const numerator = new BigNumber(20);
+            const denominator = new BigNumber(9989);
+            const target = new BigNumber(500);
+            // rounding error = ((20*500/9989) - floor(20*500/9989)) / (20*500/9989) = 0.011%
+            const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
+            expect(isRoundingError).to.be.true();
+        });
+    });

    describe('LibOrder', () => {
        describe('getOrderSchema', () => {
@@ -93,96 +122,4 @@ describe('Exchange libs', () => {
            });
        });
    });
-
-    describe('LibMath', () => {
-        describe('isRoundingError', () => {
-            it('should return false if there is a rounding error of 0.1%', async () => {
-                const numerator = new BigNumber(20);
-                const denominator = new BigNumber(999);
-                const target = new BigNumber(50);
-                // rounding error = ((20*50/999) - floor(20*50/999)) / (20*50/999) = 0.1%
-                const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
-                expect(isRoundingError).to.be.false();
-            });
-
-            it('should return false if there is a rounding of 0.09%', async () => {
-                const numerator = new BigNumber(20);
-                const denominator = new BigNumber(9991);
-                const target = new BigNumber(500);
-                // rounding error = ((20*500/9991) - floor(20*500/9991)) / (20*500/9991) = 0.09%
-                const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
-                expect(isRoundingError).to.be.false();
-            });
-
-            it('should return true if there is a rounding error of 0.11%', async () => {
-                const numerator = new BigNumber(20);
-                const denominator = new BigNumber(9989);
-                const target = new BigNumber(500);
-                // rounding error = ((20*500/9989) - floor(20*500/9989)) / (20*500/9989) = 0.011%
-                const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
-                expect(isRoundingError).to.be.true();
-            });
-
-            it('should return true if there is a rounding error > 0.1%', async () => {
-                const numerator = new BigNumber(3);
-                const denominator = new BigNumber(7);
-                const target = new BigNumber(10);
-                // rounding error = ((3*10/7) - floor(3*10/7)) / (3*10/7) = 6.67%
-                const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
-                expect(isRoundingError).to.be.true();
-            });
-
-            it('should return false when there is no rounding error', async () => {
-                const numerator = new BigNumber(1);
-                const denominator = new BigNumber(2);
-                const target = new BigNumber(10);
-
-                const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
-                expect(isRoundingError).to.be.false();
-            });
-
-            it('should return false when there is rounding error <= 0.1%', async () => {
-                // randomly generated numbers
-                const numerator = new BigNumber(76564);
-                const denominator = new BigNumber(676373677);
-                const target = new BigNumber(105762562);
-                // rounding error = ((76564*105762562/676373677) - floor(76564*105762562/676373677)) /
-                // (76564*105762562/676373677) = 0.0007%
-                const isRoundingError = await libs.publicIsRoundingError.callAsync(numerator, denominator, target);
-                expect(isRoundingError).to.be.false();
-            });
-        });
-
-        describe('getPartialAmount', () => {
-            it('should return the numerator/denominator*target', async () => {
-                const numerator = new BigNumber(1);
-                const denominator = new BigNumber(2);
-                const target = new BigNumber(10);
-
-                const partialAmount = await libs.publicGetPartialAmount.callAsync(numerator, denominator, target);
-                const expectedPartialAmount = 5;
-                expect(partialAmount).to.be.bignumber.equal(expectedPartialAmount);
-            });
-
-            it('should round down', async () => {
-                const numerator = new BigNumber(2);
-                const denominator = new BigNumber(3);
-                const target = new BigNumber(10);
-
-                const partialAmount = await libs.publicGetPartialAmount.callAsync(numerator, denominator, target);
-                const expectedPartialAmount = 6;
-                expect(partialAmount).to.be.bignumber.equal(expectedPartialAmount);
-            });
-
-            it('should round .5 down', async () => {
-                const numerator = new BigNumber(1);
-                const denominator = new BigNumber(20);
-                const target = new BigNumber(10);
-
-                const partialAmount = await libs.publicGetPartialAmount.callAsync(numerator, denominator, target);
-                const expectedPartialAmount = 0;
-                expect(partialAmount).to.be.bignumber.equal(expectedPartialAmount);
-            });
-        });
-    });
 });
--- a/packages/contracts/test/utils/artifacts.ts
+++ b/packages/contracts/test/utils/artifacts.ts
@@ -16,6 +16,7 @@ import * as MultiSigWalletWithTimeLock from '../../artifacts/MultiSigWalletWithT
 import * as TestAssetProxyDispatcher from '../../artifacts/TestAssetProxyDispatcher.json';
 import * as TestAssetProxyOwner from '../../artifacts/TestAssetProxyOwner.json';
 import * as TestConstants from '../../artifacts/TestConstants.json';
+import * as TestExchangeInternals from '../../artifacts/TestExchangeInternals.json';
 import * as TestLibBytes from '../../artifacts/TestLibBytes.json';
 import * as TestLibs from '../../artifacts/TestLibs.json';
 import * as TestSignatureValidator from '../../artifacts/TestSignatureValidator.json';
@@ -46,6 +47,7 @@ export const artifacts = {
    TestConstants: (TestConstants as any) as ContractArtifact,
    TestLibBytes: (TestLibBytes as any) as ContractArtifact,
    TestLibs: (TestLibs as any) as ContractArtifact,
+    TestExchangeInternals: (TestExchangeInternals as any) as ContractArtifact,
    TestSignatureValidator: (TestSignatureValidator as any) as ContractArtifact,
    Validator: (Validator as any) as ContractArtifact,
    Wallet: (Wallet as any) as ContractArtifact,
--- a/packages/contracts/test/utils/assertions.ts
+++ b/packages/contracts/test/utils/assertions.ts
@@ -15,6 +15,14 @@ let nodeType: NodeType | undefined;
 // resolve with either a transaction receipt or a transaction hash.
 export type sendTransactionResult = Promise<TransactionReceipt | TransactionReceiptWithDecodedLogs | string>;

+/**
+ * Returns ganacheError if the backing Ethereum node is Ganache and gethError
+ * if it is Geth.
+ * @param ganacheError the error to be returned if the backing node is Ganache.
+ * @param gethError the error to be returned if the backing node is Geth.
+ * @returns either the given ganacheError or gethError depending on the backing
+ * node.
+ */
 async function _getGanacheOrGethError(ganacheError: string, gethError: string): Promise<string> {
    if (_.isUndefined(nodeType)) {
        nodeType = await web3Wrapper.getNodeTypeAsync();
@@ -41,6 +49,25 @@ async function _getContractCallFailedErrorMessageAsync(): Promise<string> {
    return _getGanacheOrGethError('revert', 'Contract call failed');
 }

+/**
+ * Returns the expected error message for an 'invalid opcode' resulting from a
+ * contract call. The exact error message depends on the backing Ethereum node.
+ */
+export async function getInvalidOpcodeErrorMessageForCallAsync(): Promise<string> {
+    return _getGanacheOrGethError('invalid opcode', 'Contract call failed');
+}
+
+/**
+ * Returns the expected error message for the given revert reason resulting from
+ * a sendTransaction call. The exact error message depends on the backing
+ * Ethereum node and whether it supports revert reasons.
+ * @param reason a specific revert reason.
+ * @returns the expected error message.
+ */
+export async function getRevertReasonOrErrorMessageForSendTransactionAsync(reason: RevertReason): Promise<string> {
+    return _getGanacheOrGethError(reason, 'always failing transaction');
+}
+
 /**
 * Rejects if the given Promise does not reject with an error indicating
 * insufficient funds.
--- a/packages/contracts/test/utils/combinatorial_utils.ts
+++ b/packages/contracts/test/utils/combinatorial_utils.ts
@@ -0,0 +1,113 @@
+import { BigNumber } from '@0xproject/utils';
+import * as combinatorics from 'js-combinatorics';
+
+import { testWithReferenceFuncAsync } from './test_with_reference';
+
+// A set of values corresponding to the uint256 type in Solidity. This set
+// contains some notable edge cases, including some values which will overflow
+// the uint256 type when used in different mathematical operations.
+export const uint256Values = [
+    new BigNumber(0),
+    new BigNumber(1),
+    new BigNumber(2),
+    // Non-trivial big number.
+    new BigNumber(2).pow(64),
+    // Max that does not overflow when squared.
+    new BigNumber(2).pow(128).minus(1),
+    // Min that does overflow when squared.
+    new BigNumber(2).pow(128),
+    // Max that does not overflow when doubled.
+    new BigNumber(2).pow(255).minus(1),
+    // Min that does overflow when doubled.
+    new BigNumber(2).pow(255),
+    // Max that does not overflow.
+    new BigNumber(2).pow(256).minus(1),
+];
+
+// A set of values corresponding to the bytes32 type in Solidity.
+export const bytes32Values = [
+    // Min
+    '0x0000000000000000000000000000000000000000000000000000000000000000',
+    '0x0000000000000000000000000000000000000000000000000000000000000001',
+    '0x0000000000000000000000000000000000000000000000000000000000000002',
+    // Non-trivial big number.
+    '0x000000000000f000000000000000000000000000000000000000000000000000',
+    // Max
+    '0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff',
+];
+
+export async function testCombinatoriallyWithReferenceFuncAsync<P0, P1, R>(
+    name: string,
+    referenceFunc: (p0: P0, p1: P1) => Promise<R>,
+    testFunc: (p0: P0, p1: P1) => Promise<R>,
+    allValues: [P0[], P1[]],
+): Promise<void>;
+export async function testCombinatoriallyWithReferenceFuncAsync<P0, P1, P2, R>(
+    name: string,
+    referenceFunc: (p0: P0, p1: P1, p2: P2) => Promise<R>,
+    testFunc: (p0: P0, p1: P1, p2: P2) => Promise<R>,
+    allValues: [P0[], P1[], P2[]],
+): Promise<void>;
+export async function testCombinatoriallyWithReferenceFuncAsync<P0, P1, P2, P3, R>(
+    name: string,
+    referenceFunc: (p0: P0, p1: P1, p2: P2, p3: P3) => Promise<R>,
+    testFunc: (p0: P0, p1: P1, p2: P2, p3: P3) => Promise<R>,
+    allValues: [P0[], P1[], P2[], P3[]],
+): Promise<void>;
+export async function testCombinatoriallyWithReferenceFuncAsync<P0, P1, P2, P3, P4, R>(
+    name: string,
+    referenceFunc: (p0: P0, p1: P1, p2: P2, p3: P3, p4: P4) => Promise<R>,
+    testFunc: (p0: P0, p1: P1, p2: P2, p3: P3, p4: P4) => Promise<R>,
+    allValues: [P0[], P1[], P2[], P3[], P4[]],
+): Promise<void>;
+
+/**
+ * Uses combinatorics to test the behavior of a test function by comparing it to
+ * the expected behavior (defined by a reference function) for a large number of
+ * possible input values.
+ *
+ * First generates test cases by taking the cartesian product of the given
+ * values. Each test case is a set of N values corresponding to the N arguments
+ * for the test func and the reference func. For each test case, first the
+ * reference function will be called to obtain an "expected result", or if the
+ * reference function throws/rejects, an "expected error". Next, the test
+ * function will be called to obtain an "actual result", or if the test function
+ * throws/rejects, an "actual error". Each test case passes if at least one of
+ * the following conditions is met:
+ *
+ * 1) Neither the reference function or the test function throw and the
+ * "expected result" equals the "actual result".
+ *
+ * 2) Both the reference function and the test function throw and the "actual
+ * error" message *contains* the "expected error" message.
+ *
+ * The first test case which does not meet one of these conditions will cause
+ * the entire test to fail and this function will throw/reject.
+ *
+ * @param referenceFuncAsync a reference function implemented in pure
+ * JavaScript/TypeScript which accepts N arguments and returns the "expected
+ * result" or "expected error" for a given test case.
+ * @param testFuncAsync a test function which, e.g., makes a call or sends a
+ * transaction to a contract. It accepts the same N arguments returns the
+ * "actual result" or "actual error" for a given test case.
+ * @param values an array of N arrays. Each inner array is a set of possible
+ * values which are passed into both the reference function and the test
+ * function.
+ * @return A Promise that resolves if the test passes and rejects if the test
+ * fails, according to the rules described above.
+ */
+export async function testCombinatoriallyWithReferenceFuncAsync(
+    name: string,
+    referenceFuncAsync: (...args: any[]) => Promise<any>,
+    testFuncAsync: (...args: any[]) => Promise<any>,
+    allValues: any[],
+): Promise<void> {
+    const testCases = combinatorics.cartesianProduct(...allValues);
+    let counter = 0;
+    testCases.forEach(async testCase => {
+        counter += 1;
+        it(`${name} ${counter}/${testCases.length}`, async () => {
+            await testWithReferenceFuncAsync(referenceFuncAsync, testFuncAsync, testCase as any);
+        });
+    });
+}
--- a/packages/contracts/test/utils/fill_order_combinatorial_utils.ts
+++ b/packages/contracts/test/utils/fill_order_combinatorial_utils.ts
@@ -46,16 +46,16 @@ chaiSetup.configure();
 const expect = chai.expect;

 /**
- * Instantiates a new instance of CoreCombinatorialUtils. Since this method has some
+ * Instantiates a new instance of FillOrderCombinatorialUtils. Since this method has some
 * required async setup, a factory method is required.
 * @param web3Wrapper Web3Wrapper instance
 * @param txDefaults Default Ethereum tx options
- * @return CoreCombinatorialUtils instance
+ * @return FillOrderCombinatorialUtils instance
 */
-export async function coreCombinatorialUtilsFactoryAsync(
+export async function fillOrderCombinatorialUtilsFactoryAsync(
    web3Wrapper: Web3Wrapper,
    txDefaults: Partial<TxData>,
-): Promise<CoreCombinatorialUtils> {
+): Promise<FillOrderCombinatorialUtils> {
    const accounts = await web3Wrapper.getAvailableAddressesAsync();
    const userAddresses = _.slice(accounts, 0, 5);
    const [ownerAddress, makerAddress, takerAddress] = userAddresses;
@@ -123,7 +123,7 @@ export async function coreCombinatorialUtilsFactoryAsync(
        exchangeContract.address,
    );

-    const coreCombinatorialUtils = new CoreCombinatorialUtils(
+    const fillOrderCombinatorialUtils = new FillOrderCombinatorialUtils(
        orderFactory,
        ownerAddress,
        makerAddress,
@@ -133,10 +133,10 @@ export async function coreCombinatorialUtilsFactoryAsync(
        exchangeWrapper,
        assetWrapper,
    );
-    return coreCombinatorialUtils;
+    return fillOrderCombinatorialUtils;
 }

-export class CoreCombinatorialUtils {
+export class FillOrderCombinatorialUtils {
    public orderFactory: OrderFactoryFromScenario;
    public ownerAddress: string;
    public makerAddress: string;
@@ -240,7 +240,7 @@ export class CoreCombinatorialUtils {
            // AllowanceAmountScenario.TooLow,
            // AllowanceAmountScenario.Unlimited,
        ];
-        const fillScenarioArrays = CoreCombinatorialUtils._getAllCombinations([
+        const fillScenarioArrays = FillOrderCombinatorialUtils._getAllCombinations([
            takerScenarios,
            feeRecipientScenarios,
            makerAssetAmountScenario,
@@ -309,7 +309,7 @@ export class CoreCombinatorialUtils {
        } else {
            const result = [];
            const restOfArrays = arrays.slice(1);
-            const allCombinationsOfRemaining = CoreCombinatorialUtils._getAllCombinations(restOfArrays); // recur with the rest of array
+            const allCombinationsOfRemaining = FillOrderCombinatorialUtils._getAllCombinations(restOfArrays); // recur with the rest of array
            // tslint:disable:prefer-for-of
            for (let i = 0; i < allCombinationsOfRemaining.length; i++) {
                for (let j = 0; j < arrays[0].length; j++) {
--- a/packages/contracts/test/utils/test_with_reference.ts
+++ b/packages/contracts/test/utils/test_with_reference.ts
@@ -0,0 +1,119 @@
+import * as chai from 'chai';
+import * as _ from 'lodash';
+
+import { chaiSetup } from './chai_setup';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+export async function testWithReferenceFuncAsync<P0, R>(
+    referenceFunc: (p0: P0) => Promise<R>,
+    testFunc: (p0: P0) => Promise<R>,
+    values: [P0],
+): Promise<void>;
+export async function testWithReferenceFuncAsync<P0, P1, R>(
+    referenceFunc: (p0: P0, p1: P1) => Promise<R>,
+    testFunc: (p0: P0, p1: P1) => Promise<R>,
+    values: [P0, P1],
+): Promise<void>;
+export async function testWithReferenceFuncAsync<P0, P1, P2, R>(
+    referenceFunc: (p0: P0, p1: P1, p2: P2) => Promise<R>,
+    testFunc: (p0: P0, p1: P1, p2: P2) => Promise<R>,
+    values: [P0, P1, P2],
+): Promise<void>;
+export async function testWithReferenceFuncAsync<P0, P1, P2, P3, R>(
+    referenceFunc: (p0: P0, p1: P1, p2: P2, p3: P3) => Promise<R>,
+    testFunc: (p0: P0, p1: P1, p2: P2, p3: P3) => Promise<R>,
+    values: [P0, P1, P2, P3],
+): Promise<void>;
+export async function testWithReferenceFuncAsync<P0, P1, P2, P3, P4, R>(
+    referenceFunc: (p0: P0, p1: P1, p2: P2, p3: P3, p4: P4) => Promise<R>,
+    testFunc: (p0: P0, p1: P1, p2: P2, p3: P3, p4: P4) => Promise<R>,
+    values: [P0, P1, P2, P3, P4],
+): Promise<void>;
+
+/**
+ * Tests the behavior of a test function by comparing it to the expected
+ * behavior (defined by a reference function).
+ *
+ * First the reference function will be called to obtain an "expected result",
+ * or if the reference function throws/rejects, an "expected error". Next, the
+ * test function will be called to obtain an "actual result", or if the test
+ * function throws/rejects, an "actual error". The test passes if at least one
+ * of the following conditions is met:
+ *
+ * 1) Neither the reference function or the test function throw and the
+ * "expected result" equals the "actual result".
+ *
+ * 2) Both the reference function and the test function throw and the "actual
+ * error" message *contains* the "expected error" message.
+ *
+ * @param referenceFuncAsync a reference function implemented in pure
+ * JavaScript/TypeScript which accepts N arguments and returns the "expected
+ * result" or throws/rejects with the "expected error".
+ * @param testFuncAsync a test function which, e.g., makes a call or sends a
+ * transaction to a contract. It accepts the same N arguments returns the
+ * "actual result" or throws/rejects with the "actual error".
+ * @param values an array of N values, where each value corresponds in-order to
+ * an argument to both the test function and the reference function.
+ * @return A Promise that resolves if the test passes and rejects if the test
+ * fails, according to the rules described above.
+ */
+export async function testWithReferenceFuncAsync(
+    referenceFuncAsync: (...args: any[]) => Promise<any>,
+    testFuncAsync: (...args: any[]) => Promise<any>,
+    values: any[],
+): Promise<void> {
+    let expectedResult: any;
+    let expectedErr: string | undefined;
+    try {
+        expectedResult = await referenceFuncAsync(...values);
+    } catch (e) {
+        expectedErr = e.message;
+    }
+    let actualResult: any | undefined;
+    try {
+        actualResult = await testFuncAsync(...values);
+        if (!_.isUndefined(expectedErr)) {
+            throw new Error(
+                `Expected error containing ${expectedErr} but got no error\n\tTest case: ${_getTestCaseString(
+                    referenceFuncAsync,
+                    values,
+                )}`,
+            );
+        }
+    } catch (e) {
+        if (_.isUndefined(expectedErr)) {
+            throw new Error(`${e.message}\n\tTest case: ${_getTestCaseString(referenceFuncAsync, values)}`);
+        } else {
+            expect(e.message).to.contain(
+                expectedErr,
+                `${e.message}\n\tTest case: ${_getTestCaseString(referenceFuncAsync, values)}`,
+            );
+        }
+    }
+    if (!_.isUndefined(actualResult) && !_.isUndefined(expectedResult)) {
+        expect(actualResult).to.deep.equal(
+            expectedResult,
+            `Test case: ${_getTestCaseString(referenceFuncAsync, values)}`,
+        );
+    }
+}
+
+function _getTestCaseString(referenceFuncAsync: (...args: any[]) => Promise<any>, values: any[]): string {
+    const paramNames = _getParameterNames(referenceFuncAsync);
+    return JSON.stringify(_.zipObject(paramNames, values));
+}
+
+// Source: https://stackoverflow.com/questions/1007981/how-to-get-function-parameter-names-values-dynamically
+function _getParameterNames(func: (...args: any[]) => any): string[] {
+    return _.toString(func)
+        .replace(/[/][/].*$/gm, '') // strip single-line comments
+        .replace(/\s+/g, '') // strip white space
+        .replace(/[/][*][^/*]*[*][/]/g, '') // strip multi-line comments
+        .split('){', 1)[0]
+        .replace(/^[^(]*[(]/, '') // extract the parameters
+        .replace(/=[^,]+/g, '') // strip any ES6 defaults
+        .split(',')
+        .filter(Boolean); // split & filter [""]
+}
--- a/packages/fill-scenarios/CHANGELOG.json
+++ b/packages/fill-scenarios/CHANGELOG.json
@@ -1,4 +1,14 @@
 [
+    {
+        "version": "1.0.1-rc.3",
+        "changes": [
+            {
+                "note":
+                    "Updated to use latest orderFactory interface, fixed `feeRecipient` spelling error in public interface",
+                "pr": 936
+            }
+        ]
+    },
    {
        "version": "1.0.1-rc.2",
        "changes": [
--- a/packages/fill-scenarios/src/fill_scenarios.ts
+++ b/packages/fill-scenarios/src/fill_scenarios.ts
@@ -61,7 +61,7 @@ export class FillScenarios {
        makerAddress: string,
        takerAddress: string,
        fillableAmount: BigNumber,
-        feeRecepientAddress: string,
+        feeRecipientAddress: string,
        expirationTimeSeconds?: BigNumber,
    ): Promise<SignedOrder> {
        return this._createAsymmetricFillableSignedOrderWithFeesAsync(
@@ -73,7 +73,7 @@ export class FillScenarios {
            takerAddress,
            fillableAmount,
            fillableAmount,
-            feeRecepientAddress,
+            feeRecipientAddress,
            expirationTimeSeconds,
        );
    }
@@ -88,7 +88,7 @@ export class FillScenarios {
    ): Promise<SignedOrder> {
        const makerFee = new BigNumber(0);
        const takerFee = new BigNumber(0);
-        const feeRecepientAddress = constants.NULL_ADDRESS;
+        const feeRecipientAddress = constants.NULL_ADDRESS;
        return this._createAsymmetricFillableSignedOrderWithFeesAsync(
            makerAssetData,
            takerAssetData,
@@ -98,7 +98,7 @@ export class FillScenarios {
            takerAddress,
            makerFillableAmount,
            takerFillableAmount,
-            feeRecepientAddress,
+            feeRecipientAddress,
            expirationTimeSeconds,
        );
    }
@@ -148,7 +148,7 @@ export class FillScenarios {
        takerAddress: string,
        makerFillableAmount: BigNumber,
        takerFillableAmount: BigNumber,
-        feeRecepientAddress: string,
+        feeRecipientAddress: string,
        expirationTimeSeconds?: BigNumber,
    ): Promise<SignedOrder> {
        const decodedMakerAssetData = assetDataUtils.decodeAssetDataOrThrow(makerAssetData);
@@ -194,17 +194,19 @@ export class FillScenarios {
        const signedOrder = await orderFactory.createSignedOrderAsync(
            this._web3Wrapper.getProvider(),
            makerAddress,
-            takerAddress,
-            senderAddress,
-            makerFee,
-            takerFee,
            makerFillableAmount,
            makerAssetData,
            takerFillableAmount,
            takerAssetData,
            this._exchangeAddress,
-            feeRecepientAddress,
-            expirationTimeSeconds,
+            {
+                takerAddress,
+                senderAddress,
+                makerFee,
+                takerFee,
+                feeRecipientAddress,
+                expirationTimeSeconds,
+            },
        );
        return signedOrder;
    }
--- a/packages/json-schemas/CHANGELOG.json
+++ b/packages/json-schemas/CHANGELOG.json
@@ -1,9 +1,14 @@
 [
    {
-        "version": "2.0.0",
+        "version": "1.0.1-rc.4",
        "changes": [
            {
-                "note": "Upgrade Relayer API schemas for relayer API V1"
+                "note": "Change hexSchema to match `0x`",
+                "pr": 937
+            },
+            {
+                "note": "Upgrade Relayer API schemas for relayer API V2",
+                "pr": 916
            }
        ]
    },
--- a/packages/json-schemas/schemas/basic_type_schemas.ts
+++ b/packages/json-schemas/schemas/basic_type_schemas.ts
@@ -7,7 +7,7 @@ export const addressSchema = {
 export const hexSchema = {
    id: '/hexSchema',
    type: 'string',
-    pattern: '^0x([0-9a-f][0-9a-f])+$',
+    pattern: '^0x(([0-9a-f][0-9a-f])+)?$',
 };

 export const numberSchema = {
--- a/packages/json-schemas/test/schema_test.ts
+++ b/packages/json-schemas/test/schema_test.ts
@@ -96,7 +96,7 @@ describe('Schema', () => {
            validateAgainstSchema(testCases, hexSchema);
        });
        it('should fail for invalid hex string', () => {
-            const testCases = ['0x', '0', '0xzzzzzzB11a196601eD2ce54B665CaFEca0347D42'];
+            const testCases = ['0', '0xzzzzzzB11a196601eD2ce54B665CaFEca0347D42'];
            const shouldFail = true;
            validateAgainstSchema(testCases, hexSchema, shouldFail);
        });
--- a/packages/migrations/artifacts/2.0.0/AssetProxyOwner.json
+++ b/packages/migrations/artifacts/2.0.0/AssetProxyOwner.json
@@ -44468,11 +44468,5 @@
 			}
 		}
 	},
-	"networks": {
-		"50": {
-			"address": "0x34d402f14d58e001d8efbe6585051bf9706aa064",
-			"links": {},
-			"constructorArgs": "[[\"0x5409ed021d9299bf6814279a6a1411a7e866a631\",\"0x6ecbe1db9ef729cbe972c83fb886247691fb6beb\"],[\"0x1dc4c1cefef38a777b15aa20260a54e584b16c48\",\"0x1d7022f5b17d2f8b695918fb48fa1089c9f85401\"],\"2\",\"0\"]"
-		}
-	}
+	"networks": {}
 }
--- a/packages/migrations/artifacts/2.0.0/ERC20Proxy.json
+++ b/packages/migrations/artifacts/2.0.0/ERC20Proxy.json
@@ -252,11 +252,5 @@
 			}
 		}
 	},
-	"networks": {
-		"50": {
-			"address": "0x1dc4c1cefef38a777b15aa20260a54e584b16c48",
-			"links": {},
-			"constructorArgs": "[]"
-		}
-	}
+	"networks": {}
 }
--- a/packages/migrations/artifacts/2.0.0/ERC721Proxy.json
+++ b/packages/migrations/artifacts/2.0.0/ERC721Proxy.json
@@ -252,11 +252,5 @@
 			}
 		}
 	},
-	"networks": {
-		"50": {
-			"address": "0x1d7022f5b17d2f8b695918fb48fa1089c9f85401",
-			"links": {},
-			"constructorArgs": "[]"
-		}
-	}
+	"networks": {}
 }
--- a/packages/migrations/artifacts/2.0.0/ERC721Token.json
+++ b/packages/migrations/artifacts/2.0.0/ERC721Token.json
--- a/packages/migrations/artifacts/2.0.0/Exchange.json
+++ b/packages/migrations/artifacts/2.0.0/Exchange.json
@@ -2229,11 +2229,5 @@
 			}
 		}
 	},
-	"networks": {
-		"50": {
-			"address": "0x48bacb9266a570d521063ef5dd96e61686dbe788",
-			"links": {},
-			"constructorArgs": "[\"0xf47261b0000000000000000000000000871dd7c2b4b25e1aa18728e9d5f2af4c4e431f5c\"]"
-		}
-	}
-}
+	"networks": {}
+}
--- a/packages/migrations/artifacts/2.0.0/MultiSigWalletWithTimeLockExceptRemoveAuthorizedAddress.json
+++ b/packages/migrations/artifacts/2.0.0/MultiSigWalletWithTimeLockExceptRemoveAuthorizedAddress.json
--- a/packages/migrations/artifacts/2.0.0/WETH9.json
+++ b/packages/migrations/artifacts/2.0.0/WETH9.json
@@ -326,11 +326,5 @@
 			}
 		}
 	},
-	"networks": {
-		"50": {
-			"address": "0x0b1ba0af832d7c05fd64161e0db78e85978e8082",
-			"links": {},
-			"constructorArgs": "[]"
-		}
-	}
+	"networks": {}
 }
--- a/packages/migrations/artifacts/2.0.0/ZRXToken.json
+++ b/packages/migrations/artifacts/2.0.0/ZRXToken.json
@@ -10028,4 +10028,4 @@
 			"constructorArgs": "[]"
 		}
 	}
-}
+}
--- a/packages/order-utils/CHANGELOG.json
+++ b/packages/order-utils/CHANGELOG.json
@@ -1,4 +1,18 @@
 [
+    {
+        "version": "1.0.1-rc.3",
+        "changes": [
+            {
+                "note":
+                    "Added a synchronous `createOrder` method in `orderFactory`, updated public interfaces to support some optional parameters",
+                "pr": 936
+            },
+            {
+                "note": "Added marketUtils",
+                "pr": 937
+            }
+        ]
+    },
    {
        "version": "1.0.1-rc.2",
        "changes": [
--- a/packages/order-utils/src/constants.ts
+++ b/packages/order-utils/src/constants.ts
@@ -2,6 +2,7 @@ import { BigNumber } from '@0xproject/utils';

 export const constants = {
    NULL_ADDRESS: '0x0000000000000000000000000000000000000000',
+    NULL_BYTES: '0x',
    // tslint:disable-next-line:custom-no-magic-numbers
    UNLIMITED_ALLOWANCE_IN_BASE_UNITS: new BigNumber(2).pow(256).minus(1),
    TESTRPC_NETWORK_ID: 50,
@@ -10,4 +11,6 @@ export const constants = {
    ERC721_ASSET_DATA_MINIMUM_BYTE_LENGTH: 53,
    SELECTOR_LENGTH: 4,
    BASE_16: 16,
+    INFINITE_TIMESTAMP_SEC: new BigNumber(2524604400), // Close to infinite
+    ZERO_AMOUNT: new BigNumber(0),
 };
--- a/packages/order-utils/src/index.ts
+++ b/packages/order-utils/src/index.ts
@@ -13,7 +13,15 @@ export { orderFactory } from './order_factory';
 export { constants } from './constants';
 export { crypto } from './crypto';
 export { generatePseudoRandomSalt } from './salt';
-export { OrderError, MessagePrefixType, MessagePrefixOpts, EIP712Parameter, EIP712Schema, EIP712Types } from './types';
+export {
+    CreateOrderOpts,
+    OrderError,
+    MessagePrefixType,
+    MessagePrefixOpts,
+    EIP712Parameter,
+    EIP712Schema,
+    EIP712Types,
+} from './types';
 export { AbstractBalanceAndProxyAllowanceFetcher } from './abstract/abstract_balance_and_proxy_allowance_fetcher';
 export { AbstractOrderFilledCancelledFetcher } from './abstract/abstract_order_filled_cancelled_fetcher';
 export { BalanceAndProxyAllowanceLazyStore } from './store/balance_and_proxy_allowance_lazy_store';
@@ -24,3 +32,4 @@ export { assetDataUtils } from './asset_data_utils';
 export { EIP712Utils } from './eip712_utils';
 export { OrderValidationUtils } from './order_validation_utils';
 export { ExchangeTransferSimulator } from './exchange_transfer_simulator';
+export { marketUtils } from './market_utils';
--- a/packages/order-utils/src/market_utils.ts
+++ b/packages/order-utils/src/market_utils.ts
@@ -0,0 +1,133 @@
+import { schemas } from '@0xproject/json-schemas';
+import { SignedOrder } from '@0xproject/types';
+import { BigNumber } from '@0xproject/utils';
+import * as _ from 'lodash';
+
+import { assert } from './assert';
+import { constants } from './constants';
+
+export const marketUtils = {
+    /**
+     * Takes an array of orders and returns a subset of those orders that has enough makerAssetAmount (taking into account on-chain balances,
+     * allowances, and partial fills) in order to fill the input makerAssetFillAmount plus slippageBufferAmount. Iterates from first order to last.
+     * Sort the input by ascending rate in order to get the subset of orders that will cost the least ETH.
+     * @param   signedOrders                        An array of objects that conform to the SignedOrder interface. All orders should specify the same makerAsset.
+     *                                              All orders should specify WETH as the takerAsset.
+     * @param   remainingFillableMakerAssetAmounts  An array of BigNumbers corresponding to the signedOrders parameter.
+     *                                              You can use OrderStateUtils @0xproject/order-utils to perform blockchain lookups
+     *                                              for these values.
+     * @param   makerAssetFillAmount                The amount of makerAsset desired to be filled.
+     * @param   slippageBufferAmount                An additional amount of makerAsset to be covered by the result in case of trade collisions or partial fills.
+     * @return  Resulting orders and remaining fill amount that could not be covered by the input.
+     */
+    findOrdersThatCoverMakerAssetFillAmount(
+        signedOrders: SignedOrder[],
+        remainingFillableMakerAssetAmounts: BigNumber[],
+        makerAssetFillAmount: BigNumber,
+        slippageBufferAmount: BigNumber = constants.ZERO_AMOUNT,
+    ): { resultOrders: SignedOrder[]; remainingFillAmount: BigNumber } {
+        assert.doesConformToSchema('signedOrders', signedOrders, schemas.signedOrdersSchema);
+        _.forEach(remainingFillableMakerAssetAmounts, (amount, index) =>
+            assert.isValidBaseUnitAmount(`remainingFillableMakerAssetAmount[${index}]`, amount),
+        );
+        assert.isValidBaseUnitAmount('makerAssetFillAmount', makerAssetFillAmount);
+        assert.isValidBaseUnitAmount('slippageBufferAmount', slippageBufferAmount);
+        assert.assert(
+            signedOrders.length === remainingFillableMakerAssetAmounts.length,
+            'Expected signedOrders.length to equal remainingFillableMakerAssetAmounts.length',
+        );
+        // calculate total amount of makerAsset needed to be filled
+        const totalFillAmount = makerAssetFillAmount.plus(slippageBufferAmount);
+        // iterate through the signedOrders input from left to right until we have enough makerAsset to fill totalFillAmount
+        const result = _.reduce(
+            signedOrders,
+            ({ resultOrders, remainingFillAmount }, order, index) => {
+                if (remainingFillAmount.lessThanOrEqualTo(constants.ZERO_AMOUNT)) {
+                    return { resultOrders, remainingFillAmount: constants.ZERO_AMOUNT };
+                } else {
+                    const makerAssetAmountAvailable = remainingFillableMakerAssetAmounts[index];
+                    // if there is no makerAssetAmountAvailable do not append order to resultOrders
+                    // if we have exceeded the total amount we want to fill set remainingFillAmount to 0
+                    return {
+                        resultOrders: makerAssetAmountAvailable.gt(constants.ZERO_AMOUNT)
+                            ? _.concat(resultOrders, order)
+                            : resultOrders,
+                        remainingFillAmount: BigNumber.max(
+                            constants.ZERO_AMOUNT,
+                            remainingFillAmount.minus(makerAssetAmountAvailable),
+                        ),
+                    };
+                }
+            },
+            { resultOrders: [] as SignedOrder[], remainingFillAmount: totalFillAmount },
+        );
+        return result;
+    },
+    /**
+     * Takes an array of orders and an array of feeOrders. Returns a subset of the feeOrders that has enough ZRX (taking into account
+     * on-chain balances, allowances, and partial fills) in order to fill the takerFees required by signedOrders plus a
+     * slippageBufferAmount. Iterates from first feeOrder to last. Sort the feeOrders by ascending rate in order to get the subset of
+     * feeOrders that will cost the least ETH.
+     * @param   signedOrders                        An array of objects that conform to the SignedOrder interface. All orders should specify ZRX as
+     *                                              the makerAsset and WETH as the takerAsset.
+     * @param   remainingFillableMakerAssetAmounts  An array of BigNumbers corresponding to the signedOrders parameter.
+     *                                              You can use OrderStateUtils @0xproject/order-utils to perform blockchain lookups
+     *                                              for these values.
+     * @param   signedFeeOrders                     An array of objects that conform to the SignedOrder interface. All orders should specify ZRX as
+     *                                              the makerAsset and WETH as the takerAsset.
+     * @param   remainingFillableFeeAmounts         An array of BigNumbers corresponding to the signedFeeOrders parameter.
+     *                                              You can use OrderStateUtils @0xproject/order-utils to perform blockchain lookups
+     *                                              for these values.
+     * @param   slippageBufferAmount                An additional amount of fee to be covered by the result in case of trade collisions or partial fills.
+     * @return  Resulting orders and remaining fee amount that could not be covered by the input.
+     */
+    findFeeOrdersThatCoverFeesForTargetOrders(
+        signedOrders: SignedOrder[],
+        remainingFillableMakerAssetAmounts: BigNumber[],
+        signedFeeOrders: SignedOrder[],
+        remainingFillableFeeAmounts: BigNumber[],
+        slippageBufferAmount: BigNumber = constants.ZERO_AMOUNT,
+    ): { resultOrders: SignedOrder[]; remainingFeeAmount: BigNumber } {
+        assert.doesConformToSchema('signedOrders', signedOrders, schemas.signedOrdersSchema);
+        _.forEach(remainingFillableMakerAssetAmounts, (amount, index) =>
+            assert.isValidBaseUnitAmount(`remainingFillableMakerAssetAmount[${index}]`, amount),
+        );
+        assert.doesConformToSchema('signedFeeOrders', signedFeeOrders, schemas.signedOrdersSchema);
+        _.forEach(remainingFillableFeeAmounts, (amount, index) =>
+            assert.isValidBaseUnitAmount(`remainingFillableFeeAmounts[${index}]`, amount),
+        );
+        assert.isValidBaseUnitAmount('slippageBufferAmount', slippageBufferAmount);
+        assert.assert(
+            signedOrders.length === remainingFillableMakerAssetAmounts.length,
+            'Expected signedOrders.length to equal remainingFillableMakerAssetAmounts.length',
+        );
+        assert.assert(
+            signedOrders.length === remainingFillableMakerAssetAmounts.length,
+            'Expected signedFeeOrders.length to equal remainingFillableFeeAmounts.length',
+        );
+        // calculate total amount of ZRX needed to fill signedOrders
+        const totalFeeAmount = _.reduce(
+            signedOrders,
+            (accFees, order, index) => {
+                const makerAssetAmountAvailable = remainingFillableMakerAssetAmounts[index];
+                const feeToFillMakerAssetAmountAvailable = makerAssetAmountAvailable
+                    .mul(order.takerFee)
+                    .div(order.makerAssetAmount);
+                return accFees.plus(feeToFillMakerAssetAmountAvailable);
+            },
+            constants.ZERO_AMOUNT,
+        );
+        const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+            signedFeeOrders,
+            remainingFillableFeeAmounts,
+            totalFeeAmount,
+            slippageBufferAmount,
+        );
+        return {
+            resultOrders,
+            remainingFeeAmount: remainingFillAmount,
+        };
+        // TODO: add more orders here to cover rounding
+        // https://github.com/0xProject/0x-protocol-specification/blob/master/v2/forwarding-contract-specification.md#over-buying-zrx
+    },
+};
--- a/packages/order-utils/src/order_factory.ts
+++ b/packages/order-utils/src/order_factory.ts
@@ -1,49 +1,63 @@
-import { ECSignature, SignedOrder } from '@0xproject/types';
+import { ECSignature, Order, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Provider } from 'ethereum-types';
 import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';

+import { constants } from './constants';
 import { orderHashUtils } from './order_hash';
 import { generatePseudoRandomSalt } from './salt';
 import { ecSignOrderHashAsync } from './signature_utils';
-import { MessagePrefixType } from './types';
+import { CreateOrderOpts, MessagePrefixType } from './types';

 export const orderFactory = {
-    async createSignedOrderAsync(
-        provider: Provider,
+    createOrder(
        makerAddress: string,
-        takerAddress: string,
-        senderAddress: string,
-        makerFee: BigNumber,
-        takerFee: BigNumber,
        makerAssetAmount: BigNumber,
        makerAssetData: string,
        takerAssetAmount: BigNumber,
        takerAssetData: string,
        exchangeAddress: string,
-        feeRecipientAddress: string,
-        expirationTimeSecondsIfExists?: BigNumber,
-    ): Promise<SignedOrder> {
-        const defaultExpirationUnixTimestampSec = new BigNumber(2524604400); // Close to infinite
-        const expirationTimeSeconds = _.isUndefined(expirationTimeSecondsIfExists)
-            ? defaultExpirationUnixTimestampSec
-            : expirationTimeSecondsIfExists;
+        createOrderOpts: CreateOrderOpts = generateDefaultCreateOrderOpts(),
+    ): Order {
+        const defaultCreateOrderOpts = generateDefaultCreateOrderOpts();
        const order = {
            makerAddress,
-            takerAddress,
-            senderAddress,
-            makerFee,
-            takerFee,
            makerAssetAmount,
            takerAssetAmount,
            makerAssetData,
            takerAssetData,
-            salt: generatePseudoRandomSalt(),
            exchangeAddress,
-            feeRecipientAddress,
-            expirationTimeSeconds,
+            takerAddress: createOrderOpts.takerAddress || defaultCreateOrderOpts.takerAddress,
+            senderAddress: createOrderOpts.senderAddress || defaultCreateOrderOpts.senderAddress,
+            makerFee: createOrderOpts.makerFee || defaultCreateOrderOpts.makerFee,
+            takerFee: createOrderOpts.takerFee || defaultCreateOrderOpts.takerFee,
+            feeRecipientAddress: createOrderOpts.feeRecipientAddress || defaultCreateOrderOpts.feeRecipientAddress,
+            salt: createOrderOpts.salt || defaultCreateOrderOpts.salt,
+            expirationTimeSeconds:
+                createOrderOpts.expirationTimeSeconds || defaultCreateOrderOpts.expirationTimeSeconds,
        };
+        return order;
+    },
+    async createSignedOrderAsync(
+        provider: Provider,
+        makerAddress: string,
+        makerAssetAmount: BigNumber,
+        makerAssetData: string,
+        takerAssetAmount: BigNumber,
+        takerAssetData: string,
+        exchangeAddress: string,
+        createOrderOpts?: CreateOrderOpts,
+    ): Promise<SignedOrder> {
+        const order = orderFactory.createOrder(
+            makerAddress,
+            makerAssetAmount,
+            makerAssetData,
+            takerAssetAmount,
+            takerAssetData,
+            exchangeAddress,
+            createOrderOpts,
+        );
        const orderHash = orderHashUtils.getOrderHashHex(order);
        const messagePrefixOpts = {
            prefixType: MessagePrefixType.EthSign,
@@ -56,6 +70,26 @@ export const orderFactory = {
    },
 };

+function generateDefaultCreateOrderOpts(): {
+    takerAddress: string;
+    senderAddress: string;
+    makerFee: BigNumber;
+    takerFee: BigNumber;
+    feeRecipientAddress: string;
+    salt: BigNumber;
+    expirationTimeSeconds: BigNumber;
+} {
+    return {
+        takerAddress: constants.NULL_ADDRESS,
+        senderAddress: constants.NULL_ADDRESS,
+        makerFee: constants.ZERO_AMOUNT,
+        takerFee: constants.ZERO_AMOUNT,
+        feeRecipientAddress: constants.NULL_ADDRESS,
+        salt: generatePseudoRandomSalt(),
+        expirationTimeSeconds: constants.INFINITE_TIMESTAMP_SEC,
+    };
+}
+
 function getVRSHexString(ecSignature: ECSignature): string {
    const ETH_SIGN_SIGNATURE_TYPE = '03';
    const vrs = `${intToHex(ecSignature.v)}${ethUtil.stripHexPrefix(ecSignature.r)}${ethUtil.stripHexPrefix(
--- a/packages/order-utils/src/types.ts
+++ b/packages/order-utils/src/types.ts
@@ -1,3 +1,5 @@
+import { BigNumber } from '@0xproject/utils';
+
 export enum OrderError {
    InvalidSignature = 'INVALID_SIGNATURE',
 }
@@ -51,3 +53,13 @@ export enum EIP712Types {
    String = 'string',
    Uint256 = 'uint256',
 }
+
+export interface CreateOrderOpts {
+    takerAddress?: string;
+    senderAddress?: string;
+    makerFee?: BigNumber;
+    takerFee?: BigNumber;
+    feeRecipientAddress?: string;
+    salt?: BigNumber;
+    expirationTimeSeconds?: BigNumber;
+}
--- a/packages/order-utils/test/market_utils_test.ts
+++ b/packages/order-utils/test/market_utils_test.ts
@@ -0,0 +1,280 @@
+import { BigNumber } from '@0xproject/utils';
+import * as chai from 'chai';
+import 'mocha';
+
+import { constants, marketUtils } from '../src';
+
+import { chaiSetup } from './utils/chai_setup';
+import { testOrderFactory } from './utils/test_order_factory';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+// tslint:disable: no-unused-expression
+describe('marketUtils', () => {
+    describe('#findOrdersThatCoverMakerAssetFillAmount', () => {
+        describe('no orders', () => {
+            it('returns empty and unchanged remainingFillAmount', async () => {
+                const fillAmount = new BigNumber(10);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    [],
+                    [],
+                    fillAmount,
+                );
+                expect(resultOrders).to.be.empty;
+                expect(remainingFillAmount).to.be.bignumber.equal(fillAmount);
+            });
+        });
+        describe('orders are completely fillable', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            const makerAssetAmount = new BigNumber(10);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that equal the makerAssetAmount
+            const remainingFillableMakerAssetAmounts = [makerAssetAmount, makerAssetAmount, makerAssetAmount];
+            it('returns input orders and zero remainingFillAmount when input exactly matches requested fill amount', async () => {
+                // try to fill 20 units of makerAsset
+                // include 10 units of slippageBufferAmount
+                const fillAmount = new BigNumber(20);
+                const slippageBufferAmount = new BigNumber(10);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    fillAmount,
+                    slippageBufferAmount,
+                );
+                expect(resultOrders).to.be.deep.equal(inputOrders);
+                expect(remainingFillAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+            it('returns input orders and zero remainingFillAmount when input has more than requested fill amount', async () => {
+                // try to fill 15 units of makerAsset
+                // include 10 units of slippageBufferAmount
+                const fillAmount = new BigNumber(15);
+                const slippageBufferAmount = new BigNumber(10);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    fillAmount,
+                    slippageBufferAmount,
+                );
+                expect(resultOrders).to.be.deep.equal(inputOrders);
+                expect(remainingFillAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+            it('returns input orders and non-zero remainingFillAmount when input has less than requested fill amount', async () => {
+                // try to fill 30 units of makerAsset
+                // include 5 units of slippageBufferAmount
+                const fillAmount = new BigNumber(30);
+                const slippageBufferAmount = new BigNumber(5);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    fillAmount,
+                    slippageBufferAmount,
+                );
+                expect(resultOrders).to.be.deep.equal(inputOrders);
+                expect(remainingFillAmount).to.be.bignumber.equal(new BigNumber(5));
+            });
+            it('returns first order and zero remainingFillAmount when requested fill amount is exactly covered by the first order', async () => {
+                // try to fill 10 units of makerAsset
+                const fillAmount = new BigNumber(10);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    fillAmount,
+                );
+                expect(resultOrders).to.be.deep.equal([inputOrders[0]]);
+                expect(remainingFillAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+            it('returns first two orders and zero remainingFillAmount when requested fill amount is over covered by the first two order', async () => {
+                // try to fill 15 units of makerAsset
+                const fillAmount = new BigNumber(15);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    fillAmount,
+                );
+                expect(resultOrders).to.be.deep.equal([inputOrders[0], inputOrders[1]]);
+                expect(remainingFillAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+        });
+        describe('orders are partially fillable', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            const makerAssetAmount = new BigNumber(10);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that cover different partial fill scenarios
+            // 1. order is completely filled already
+            // 2. order is partially fillable
+            // 3. order is completely fillable
+            const remainingFillableMakerAssetAmounts = [constants.ZERO_AMOUNT, new BigNumber(5), makerAssetAmount];
+            it('returns last two orders and non-zero remainingFillAmount when trying to fill original makerAssetAmounts', async () => {
+                // try to fill 30 units of makerAsset
+                const fillAmount = new BigNumber(30);
+                const { resultOrders, remainingFillAmount } = marketUtils.findOrdersThatCoverMakerAssetFillAmount(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    fillAmount,
+                );
+                expect(resultOrders).to.be.deep.equal([inputOrders[1], inputOrders[2]]);
+                expect(remainingFillAmount).to.be.bignumber.equal(new BigNumber(15));
+            });
+        });
+    });
+    describe('#findFeeOrdersThatCoverFeesForTargetOrders', () => {
+        // generate three signed fee orders each with 10 units of ZRX, 30 total
+        const zrxAmount = new BigNumber(10);
+        const inputFeeOrders = testOrderFactory.generateTestSignedOrders(
+            {
+                makerAssetAmount: zrxAmount,
+            },
+            3,
+        );
+        // generate remainingFillableFeeAmounts that equal the zrxAmount
+        const remainingFillableFeeAmounts = [zrxAmount, zrxAmount, zrxAmount];
+        describe('no target orders', () => {
+            it('returns empty and zero remainingFeeAmount', async () => {
+                const { resultOrders, remainingFeeAmount } = marketUtils.findFeeOrdersThatCoverFeesForTargetOrders(
+                    [],
+                    [],
+                    inputFeeOrders,
+                    remainingFillableFeeAmounts,
+                );
+                expect(resultOrders).to.be.empty;
+                expect(remainingFeeAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+        });
+        describe('no fee orders', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            // each signed order requires 10 units of takerFee
+            const makerAssetAmount = new BigNumber(10);
+            const takerFee = new BigNumber(10);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                    takerFee,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that equal the makerAssetAmount
+            const remainingFillableMakerAssetAmounts = [makerAssetAmount, makerAssetAmount, makerAssetAmount];
+            it('returns empty and non-zero remainingFeeAmount', async () => {
+                const { resultOrders, remainingFeeAmount } = marketUtils.findFeeOrdersThatCoverFeesForTargetOrders(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    [],
+                    [],
+                );
+                expect(resultOrders).to.be.empty;
+                expect(remainingFeeAmount).to.be.bignumber.equal(new BigNumber(30));
+            });
+        });
+        describe('target orders have no fees', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            const makerAssetAmount = new BigNumber(10);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that equal the makerAssetAmount
+            const remainingFillableMakerAssetAmounts = [makerAssetAmount, makerAssetAmount, makerAssetAmount];
+            it('returns empty and zero remainingFeeAmount', async () => {
+                const { resultOrders, remainingFeeAmount } = marketUtils.findFeeOrdersThatCoverFeesForTargetOrders(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    inputFeeOrders,
+                    remainingFillableFeeAmounts,
+                );
+                expect(resultOrders).to.be.empty;
+                expect(remainingFeeAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+        });
+        describe('target orders require fees and are completely fillable', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            // each signed order requires 10 units of takerFee
+            const makerAssetAmount = new BigNumber(10);
+            const takerFee = new BigNumber(10);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                    takerFee,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that equal the makerAssetAmount
+            const remainingFillableMakerAssetAmounts = [makerAssetAmount, makerAssetAmount, makerAssetAmount];
+            it('returns input fee orders and zero remainingFeeAmount', async () => {
+                const { resultOrders, remainingFeeAmount } = marketUtils.findFeeOrdersThatCoverFeesForTargetOrders(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    inputFeeOrders,
+                    remainingFillableFeeAmounts,
+                );
+                expect(resultOrders).to.be.deep.equal(inputFeeOrders);
+                expect(remainingFeeAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+        });
+        describe('target orders require fees and are partially fillable', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            // each signed order requires 10 units of takerFee
+            const makerAssetAmount = new BigNumber(10);
+            const takerFee = new BigNumber(10);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                    takerFee,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that cover different partial fill scenarios
+            // 1. order is completely filled already
+            // 2. order is partially fillable
+            // 3. order is completely fillable
+            const remainingFillableMakerAssetAmounts = [constants.ZERO_AMOUNT, new BigNumber(5), makerAssetAmount];
+            it('returns first two input fee orders and zero remainingFeeAmount', async () => {
+                const { resultOrders, remainingFeeAmount } = marketUtils.findFeeOrdersThatCoverFeesForTargetOrders(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    inputFeeOrders,
+                    remainingFillableFeeAmounts,
+                );
+                expect(resultOrders).to.be.deep.equal([inputFeeOrders[0], inputFeeOrders[1]]);
+                expect(remainingFeeAmount).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            });
+        });
+        describe('target orders require more fees than available', () => {
+            // generate three signed orders each with 10 units of makerAsset, 30 total
+            // each signed order requires 20 units of takerFee
+            const makerAssetAmount = new BigNumber(10);
+            const takerFee = new BigNumber(20);
+            const inputOrders = testOrderFactory.generateTestSignedOrders(
+                {
+                    makerAssetAmount,
+                    takerFee,
+                },
+                3,
+            );
+            // generate remainingFillableMakerAssetAmounts that equal the makerAssetAmount
+            const remainingFillableMakerAssetAmounts = [makerAssetAmount, makerAssetAmount, makerAssetAmount];
+            it('returns input fee orders and non-zero remainingFeeAmount', async () => {
+                const { resultOrders, remainingFeeAmount } = marketUtils.findFeeOrdersThatCoverFeesForTargetOrders(
+                    inputOrders,
+                    remainingFillableMakerAssetAmounts,
+                    inputFeeOrders,
+                    remainingFillableFeeAmounts,
+                );
+                expect(resultOrders).to.be.deep.equal(inputFeeOrders);
+                expect(remainingFeeAmount).to.be.bignumber.equal(new BigNumber(30));
+            });
+        });
+    });
+});
--- a/packages/order-utils/test/utils/test_order_factory.ts
+++ b/packages/order-utils/test/utils/test_order_factory.ts
@@ -0,0 +1,32 @@
+import { Order, SignedOrder } from '@0xproject/types';
+import * as _ from 'lodash';
+
+import { constants, orderFactory } from '../../src';
+
+const BASE_TEST_ORDER: Order = orderFactory.createOrder(
+    constants.NULL_ADDRESS,
+    constants.ZERO_AMOUNT,
+    constants.NULL_ADDRESS,
+    constants.ZERO_AMOUNT,
+    constants.NULL_ADDRESS,
+    constants.NULL_ADDRESS,
+);
+const BASE_TEST_SIGNED_ORDER: SignedOrder = {
+    ...BASE_TEST_ORDER,
+    signature: constants.NULL_BYTES,
+};
+
+export const testOrderFactory = {
+    generateTestSignedOrder(partialOrder: Partial<SignedOrder>): SignedOrder {
+        return transformObject(BASE_TEST_SIGNED_ORDER, partialOrder);
+    },
+    generateTestSignedOrders(partialOrder: Partial<SignedOrder>, numOrders: number): SignedOrder[] {
+        const baseTestOrders = _.map(_.range(numOrders), () => BASE_TEST_SIGNED_ORDER);
+        return _.map(baseTestOrders, order => transformObject(order, partialOrder));
+    },
+};
+
+function transformObject<T>(input: T, transformation: Partial<T>): T {
+    const copy = _.cloneDeep(input);
+    return _.assign(copy, transformation);
+}
--- a/packages/sol-resolver/CHANGELOG.json
+++ b/packages/sol-resolver/CHANGELOG.json
@@ -1,4 +1,13 @@
 [
+    {
+        "version": "1.0.5",
+        "changes": [
+            {
+                "note": "Fix a bug where RelativeFSResolver would crash when trying to read a directory",
+                "pr": 909
+            }
+        ]
+    },
    {
        "timestamp": 1532619515,
        "version": "1.0.4",
--- a/packages/sol-resolver/src/resolvers/relative_fs_resolver.ts
+++ b/packages/sol-resolver/src/resolvers/relative_fs_resolver.ts
@@ -14,7 +14,7 @@ export class RelativeFSResolver extends Resolver {
    // tslint:disable-next-line:prefer-function-over-method
    public resolveIfExists(importPath: string): ContractSource | undefined {
        const filePath = path.join(this._contractsDir, importPath);
-        if (fs.existsSync(filePath)) {
+        if (fs.existsSync(filePath) && !fs.lstatSync(filePath).isDirectory()) {
            const fileContent = fs.readFileSync(filePath).toString();
            return {
                source: fileContent,
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -213,6 +213,7 @@ export enum RevertReason {
    ValueGreaterThanZero = 'VALUE_GREATER_THAN_ZERO',
    InvalidMsgValue = 'INVALID_MSG_VALUE',
    InsufficientEthRemaining = 'INSUFFICIENT_ETH_REMAINING',
+    Uint256Overflow = 'UINT256_OVERFLOW',
 }

 export enum StatusCodes {
--- a/packages/utils/CHANGELOG.json
+++ b/packages/utils/CHANGELOG.json
@@ -1,4 +1,13 @@
 [
+    {
+        "version": "1.0.5",
+        "changes": [
+            {
+                "note": "Increased BigNumber decimal precision from 20 to 78",
+                "pr": 807
+            }
+        ]
+    },
    {
        "timestamp": 1532619515,
        "version": "1.0.4",
--- a/packages/utils/src/configured_bignumber.ts
+++ b/packages/utils/src/configured_bignumber.ts
@@ -1,9 +1,14 @@
 import { BigNumber } from 'bignumber.js';

-// By default BigNumber's `toString` method converts to exponential notation if the value has
-// more then 20 digits. We want to avoid this behavior, so we set EXPONENTIAL_AT to a high number
 BigNumber.config({
+    // By default BigNumber's `toString` method converts to exponential notation if the value has
+    // more then 20 digits. We want to avoid this behavior, so we set EXPONENTIAL_AT to a high number
    EXPONENTIAL_AT: 1000,
+    // Note(albrow): This is the lowest value for which
+    // `x.div(y).floor() === x.divToInt(y)`
+    // for all values of x and y <= MAX_UINT256, where MAX_UINT256 is the
+    // maximum number represented by the uint256 type in Solidity (2^256-1).
+    DECIMAL_PLACES: 78,
 });

 export { BigNumber };
--- a/packages/website/package.json
+++ b/packages/website/package.json
@@ -46,6 +46,7 @@
        "react-copy-to-clipboard": "^4.2.3",
        "react-document-title": "^2.0.3",
        "react-dom": "15.6.1",
+        "react-helmet": "^5.2.0",
        "react-popper": "^1.0.0-beta.6",
        "react-redux": "^5.0.3",
        "react-router-dom": "^4.1.1",
@@ -75,6 +76,7 @@
        "@types/react": "16.3.13",
        "@types/react-copy-to-clipboard": "^4.2.0",
        "@types/react-dom": "^16.0.3",
+        "@types/react-helmet": "^5.0.6",
        "@types/react-redux": "^4.4.37",
        "@types/react-router-dom": "^4.0.4",
        "@types/react-scroll": "0.0.31",
--- a/packages/website/ts/components/inputs/allowance_state_toggle.tsx
+++ b/packages/website/ts/components/inputs/allowance_state_toggle.tsx
@@ -0,0 +1,160 @@
+import { colors } from '@0xproject/react-shared';
+import { BigNumber, logUtils } from '@0xproject/utils';
+import * as _ from 'lodash';
+import * as React from 'react';
+import ReactTooltip = require('react-tooltip');
+import { Blockchain } from 'ts/blockchain';
+import { AllowanceState, AllowanceStateView } from 'ts/components/ui/allowance_state_view';
+import { Container } from 'ts/components/ui/container';
+import { PointerDirection } from 'ts/components/ui/pointer';
+import { Text } from 'ts/components/ui/text';
+import { Dispatcher } from 'ts/redux/dispatcher';
+import { BalanceErrs, Token, TokenState } from 'ts/types';
+import { analytics } from 'ts/utils/analytics';
+import { errorReporter } from 'ts/utils/error_reporter';
+import { utils } from 'ts/utils/utils';
+
+export interface AllowanceStateToggleProps {
+    networkId: number;
+    blockchain: Blockchain;
+    dispatcher: Dispatcher;
+    token: Token;
+    tokenState: TokenState;
+    userAddress: string;
+    onErrorOccurred?: (errType: BalanceErrs) => void;
+    refetchTokenStateAsync: () => Promise<void>;
+    tooltipDirection?: PointerDirection;
+}
+
+export interface AllowanceStateToggleState {
+    allowanceState: AllowanceState;
+    prevTokenState: TokenState;
+    loadingMessage?: string;
+}
+
+const DEFAULT_ALLOWANCE_AMOUNT_IN_BASE_UNITS = new BigNumber(2).pow(256).minus(1);
+
+export class AllowanceStateToggle extends React.Component<AllowanceStateToggleProps, AllowanceStateToggleState> {
+    public static defaultProps = {
+        onErrorOccurred: _.noop.bind(_),
+        tooltipDirection: PointerDirection.Right,
+    };
+    private static _getAllowanceState(tokenState: TokenState): AllowanceState {
+        if (!tokenState.isLoaded) {
+            return AllowanceState.Loading;
+        }
+        if (tokenState.allowance.gt(0)) {
+            return AllowanceState.Unlocked;
+        }
+        return AllowanceState.Locked;
+    }
+    constructor(props: AllowanceStateToggleProps) {
+        super(props);
+        const tokenState = props.tokenState;
+        this.state = {
+            allowanceState: AllowanceStateToggle._getAllowanceState(tokenState),
+            prevTokenState: tokenState,
+        };
+    }
+
+    public render(): React.ReactNode {
+        const tooltipId = `tooltip-id-${this.props.token.symbol}`;
+        return (
+            <Container cursor="pointer">
+                <ReactTooltip id={tooltipId} effect="solid" offset={{ top: 3 }}>
+                    {this._getTooltipContent()}
+                </ReactTooltip>
+                <div
+                    data-tip={true}
+                    data-for={tooltipId}
+                    data-place={this.props.tooltipDirection}
+                    onClick={this._onToggleAllowanceAsync.bind(this)}
+                >
+                    <AllowanceStateView allowanceState={this.state.allowanceState} />
+                </div>
+            </Container>
+        );
+    }
+    public componentWillReceiveProps(nextProps: AllowanceStateToggleProps): void {
+        const nextTokenState = nextProps.tokenState;
+        const prevTokenState = this.state.prevTokenState;
+        if (
+            !nextTokenState.allowance.eq(prevTokenState.allowance) ||
+            nextTokenState.isLoaded !== prevTokenState.isLoaded
+        ) {
+            const tokenState = nextProps.tokenState;
+            this.setState({
+                prevTokenState: tokenState,
+                allowanceState: AllowanceStateToggle._getAllowanceState(nextTokenState),
+            });
+        }
+    }
+    private _getTooltipContent(): React.ReactNode {
+        const symbol = this.props.token.symbol;
+        switch (this.state.allowanceState) {
+            case AllowanceState.Loading:
+                return (
+                    <Text noWrap={true} fontColor={colors.white}>
+                        {this.state.loadingMessage || 'Loading...'}
+                    </Text>
+                );
+            case AllowanceState.Locked:
+                return (
+                    <Text noWrap={true} fontColor={colors.white}>
+                        Click to enable <b>{symbol}</b> for trading
+                    </Text>
+                );
+            case AllowanceState.Unlocked:
+                return (
+                    <Text noWrap={true} fontColor={colors.white}>
+                        <b>{symbol}</b> is available for trading
+                    </Text>
+                );
+            default:
+                return null;
+        }
+    }
+    private async _onToggleAllowanceAsync(): Promise<void> {
+        // Close all tooltips
+        ReactTooltip.hide();
+        if (this.props.userAddress === '') {
+            this.props.dispatcher.updateShouldBlockchainErrDialogBeOpen(true);
+            return;
+        }
+
+        let newAllowanceAmountInBaseUnits = new BigNumber(0);
+        if (!this._isAllowanceSet()) {
+            newAllowanceAmountInBaseUnits = DEFAULT_ALLOWANCE_AMOUNT_IN_BASE_UNITS;
+        }
+        const isUnlockingToken = newAllowanceAmountInBaseUnits.gt(0);
+        this.setState({
+            allowanceState: AllowanceState.Loading,
+            loadingMessage: `${isUnlockingToken ? 'Unlocking' : 'Locking'} ${this.props.token.symbol}`,
+        });
+        const logData = {
+            tokenSymbol: this.props.token.symbol,
+            newAllowance: newAllowanceAmountInBaseUnits.toNumber(),
+        };
+        try {
+            await this.props.blockchain.setProxyAllowanceAsync(this.props.token, newAllowanceAmountInBaseUnits);
+            analytics.track('Set Allowances Success', logData);
+            await this.props.refetchTokenStateAsync();
+        } catch (err) {
+            analytics.track('Set Allowance Failure', logData);
+            this.setState({
+                allowanceState: AllowanceStateToggle._getAllowanceState(this.state.prevTokenState),
+            });
+            const errMsg = `${err}`;
+            if (utils.didUserDenyWeb3Request(errMsg)) {
+                return;
+            }
+            logUtils.log(`Unexpected error encountered: ${err}`);
+            logUtils.log(err.stack);
+            this.props.onErrorOccurred(BalanceErrs.allowanceSettingFailed);
+            errorReporter.report(err);
+        }
+    }
+    private _isAllowanceSet(): boolean {
+        return !this.props.tokenState.allowance.eq(0);
+    }
+}
--- a/packages/website/ts/components/inputs/allowance_toggle.tsx
+++ b/packages/website/ts/components/inputs/allowance_toggle.tsx
@@ -1,140 +0,0 @@
-import { Styles } from '@0xproject/react-shared';
-import { BigNumber, logUtils } from '@0xproject/utils';
-import * as _ from 'lodash';
-import Toggle from 'material-ui/Toggle';
-import * as React from 'react';
-import { Blockchain } from 'ts/blockchain';
-import { Dispatcher } from 'ts/redux/dispatcher';
-import { colors } from 'ts/style/colors';
-import { BalanceErrs, Token, TokenState } from 'ts/types';
-import { analytics } from 'ts/utils/analytics';
-import { errorReporter } from 'ts/utils/error_reporter';
-import { utils } from 'ts/utils/utils';
-
-const DEFAULT_ALLOWANCE_AMOUNT_IN_BASE_UNITS = new BigNumber(2).pow(256).minus(1);
-
-interface AllowanceToggleProps {
-    networkId: number;
-    blockchain: Blockchain;
-    dispatcher: Dispatcher;
-    token: Token;
-    tokenState: TokenState;
-    userAddress: string;
-    isDisabled?: boolean;
-    onErrorOccurred?: (errType: BalanceErrs) => void;
-    refetchTokenStateAsync: () => Promise<void>;
-}
-
-interface AllowanceToggleState {
-    isSpinnerVisible: boolean;
-    prevAllowance: BigNumber;
-}
-
-const styles: Styles = {
-    baseThumbStyle: {
-        height: 10,
-        width: 10,
-        top: 6,
-        backgroundColor: colors.white,
-        boxShadow: `0px 0px 0px ${colors.allowanceToggleShadow}`,
-    },
-    offThumbStyle: {
-        left: 4,
-    },
-    onThumbStyle: {
-        left: 25,
-    },
-    baseTrackStyle: {
-        width: 25,
-    },
-    offTrackStyle: {
-        backgroundColor: colors.grey300,
-    },
-    onTrackStyle: {
-        backgroundColor: colors.mediumBlue,
-    },
-};
-
-export class AllowanceToggle extends React.Component<AllowanceToggleProps, AllowanceToggleState> {
-    public static defaultProps = {
-        onErrorOccurred: _.noop.bind(_),
-        isDisabled: false,
-    };
-    constructor(props: AllowanceToggleProps) {
-        super(props);
-        this.state = {
-            isSpinnerVisible: false,
-            prevAllowance: props.tokenState.allowance,
-        };
-    }
-    public componentWillReceiveProps(nextProps: AllowanceToggleProps): void {
-        if (!nextProps.tokenState.allowance.eq(this.state.prevAllowance)) {
-            this.setState({
-                isSpinnerVisible: false,
-                prevAllowance: nextProps.tokenState.allowance,
-            });
-        }
-    }
-    public render(): React.ReactNode {
-        return (
-            <div className="flex">
-                <div>
-                    <Toggle
-                        disabled={this.state.isSpinnerVisible || this.props.isDisabled}
-                        toggled={this._isAllowanceSet()}
-                        onToggle={this._onToggleAllowanceAsync.bind(this)}
-                        thumbStyle={{ ...styles.baseThumbStyle, ...styles.offThumbStyle }}
-                        thumbSwitchedStyle={{ ...styles.baseThumbStyle, ...styles.onThumbStyle }}
-                        trackStyle={{ ...styles.baseTrackStyle, ...styles.offTrackStyle }}
-                        trackSwitchedStyle={{ ...styles.baseTrackStyle, ...styles.onTrackStyle }}
-                    />
-                </div>
-                {this.state.isSpinnerVisible && (
-                    <div className="pl1" style={{ paddingTop: 3 }}>
-                        <i className="zmdi zmdi-spinner zmdi-hc-spin" />
-                    </div>
-                )}
-            </div>
-        );
-    }
-    private async _onToggleAllowanceAsync(): Promise<void> {
-        if (this.props.userAddress === '') {
-            this.props.dispatcher.updateShouldBlockchainErrDialogBeOpen(true);
-            return;
-        }
-
-        this.setState({
-            isSpinnerVisible: true,
-        });
-
-        let newAllowanceAmountInBaseUnits = new BigNumber(0);
-        if (!this._isAllowanceSet()) {
-            newAllowanceAmountInBaseUnits = DEFAULT_ALLOWANCE_AMOUNT_IN_BASE_UNITS;
-        }
-        const logData = {
-            tokenSymbol: this.props.token.symbol,
-            newAllowance: newAllowanceAmountInBaseUnits.toNumber(),
-        };
-        try {
-            await this.props.blockchain.setProxyAllowanceAsync(this.props.token, newAllowanceAmountInBaseUnits);
-            analytics.track('Set Allowances Success', logData);
-            await this.props.refetchTokenStateAsync();
-        } catch (err) {
-            analytics.track('Set Allowance Failure', logData);
-            this.setState({
-                isSpinnerVisible: false,
-            });
-            const errMsg = `${err}`;
-            if (utils.didUserDenyWeb3Request(errMsg)) {
-                return;
-            }
-            logUtils.log(`Unexpected error encountered: ${err}`);
-            logUtils.log(err.stack);
-            this.props.onErrorOccurred(BalanceErrs.allowanceSettingFailed);
-            errorReporter.report(err);
-        }
-    }
-    private _isAllowanceSet(): boolean {
-        return !this.props.tokenState.allowance.eq(0);
-    }
-}
--- a/packages/website/ts/components/meta_tags.tsx
+++ b/packages/website/ts/components/meta_tags.tsx
@@ -0,0 +1,25 @@
+import * as React from 'react';
+import { Helmet } from 'react-helmet';
+
+export interface MetaTagsProps {
+    title: string;
+    description: string;
+    imgSrc?: string;
+}
+
+export const MetaTags: React.StatelessComponent<MetaTagsProps> = ({ title, description, imgSrc }) => (
+    <Helmet>
+        <title>{title}</title>
+        <meta name="description" content={description} />
+        <meta property="og:title" content={title} />
+        <meta property="og:description" content={description} />
+        <meta property="og:type" content="website" />
+        <meta property="og:image" content={imgSrc} />
+        <meta name="twitter:site" content="@0xproject" />
+        <meta name="twitter:image" content={imgSrc} />
+    </Helmet>
+);
+
+MetaTags.defaultProps = {
+    imgSrc: '/images/og_image.png',
+};
--- a/packages/website/ts/components/onboarding/onboarding_tooltip.tsx
+++ b/packages/website/ts/components/onboarding/onboarding_tooltip.tsx
@@ -24,7 +24,7 @@ export const OnboardingTooltip: React.StatelessComponent<OnboardingTooltipProps>
    );
 };
 OnboardingTooltip.defaultProps = {
-    pointerDisplay: 'left',
+    pointerDisplay: PointerDirection.Left,
 };

 OnboardingTooltip.displayName = 'OnboardingTooltip';
--- a/packages/website/ts/components/onboarding/portal_onboarding_flow.tsx
+++ b/packages/website/ts/components/onboarding/portal_onboarding_flow.tsx
@@ -21,7 +21,7 @@ import {
    WrapEthOnboardingStep2,
    WrapEthOnboardingStep3,
 } from 'ts/components/onboarding/wrap_eth_onboarding_step';
-import { AllowanceToggle } from 'ts/containers/inputs/allowance_toggle';
+import { AllowanceStateToggle } from 'ts/containers/inputs/allowance_state_toggle';
 import { BrowserType, ProviderType, ScreenWidths, Token, TokenByAddress, TokenStateByAddress } from 'ts/types';
 import { analytics } from 'ts/utils/analytics';
 import { utils } from 'ts/utils/utils';
@@ -149,8 +149,8 @@ class PlainPortalOnboardingFlow extends React.Component<PortalOnboardingFlowProp
                title: 'Step 3: Unlock Tokens',
                content: (
                    <SetAllowancesOnboardingStep
-                        zrxAllowanceToggle={this._renderZrxAllowanceToggle()}
-                        ethAllowanceToggle={this._renderEthAllowanceToggle()}
+                        zrxAllowanceToggle={this._renderZrxAllowanceStateToggle()}
+                        ethAllowanceToggle={this._renderEthAllowanceStateToggle()}
                        doesUserHaveAllowancesForWethAndZrx={this._doesUserHaveAllowancesForWethAndZrx()}
                    />
                ),
@@ -243,15 +243,15 @@ class PlainPortalOnboardingFlow extends React.Component<PortalOnboardingFlowProp
            stepIndex: this.props.stepIndex,
        });
    }
-    private _renderZrxAllowanceToggle(): React.ReactNode {
+    private _renderZrxAllowanceStateToggle(): React.ReactNode {
        const zrxToken = utils.getZrxToken(this.props.tokenByAddress);
-        return this._renderAllowanceToggle(zrxToken);
+        return this._renderAllowanceStateToggle(zrxToken);
    }
-    private _renderEthAllowanceToggle(): React.ReactNode {
+    private _renderEthAllowanceStateToggle(): React.ReactNode {
        const ethToken = utils.getEthToken(this.props.tokenByAddress);
-        return this._renderAllowanceToggle(ethToken);
+        return this._renderAllowanceStateToggle(ethToken);
    }
-    private _renderAllowanceToggle(token: Token): React.ReactNode {
+    private _renderAllowanceStateToggle(token: Token): React.ReactNode {
        if (!token) {
            return null;
        }
@@ -260,10 +260,9 @@ class PlainPortalOnboardingFlow extends React.Component<PortalOnboardingFlowProp
            return null;
        }
        return (
-            <AllowanceToggle
+            <AllowanceStateToggle
                token={token}
                tokenState={tokenStateIfExists}
-                isDisabled={!tokenStateIfExists.isLoaded}
                blockchain={this.props.blockchain}
                // tslint:disable-next-line:jsx-no-lambda
                refetchTokenStateAsync={async () => this.props.refetchTokenStateAsync(token.address)}
--- a/packages/website/ts/components/portal/portal.tsx
+++ b/packages/website/ts/components/portal/portal.tsx
@@ -12,6 +12,7 @@ import { PortalDisclaimerDialog } from 'ts/components/dialogs/portal_disclaimer_
 import { EthWrappers } from 'ts/components/eth_wrappers';
 import { FillOrder } from 'ts/components/fill_order';
 import { AssetPicker } from 'ts/components/generate_order/asset_picker';
+import { MetaTags } from 'ts/components/meta_tags';
 import { BackButton } from 'ts/components/portal/back_button';
 import { Loading } from 'ts/components/portal/loading';
 import { Menu, MenuTheme } from 'ts/components/portal/menu';
@@ -24,6 +25,7 @@ import { TradeHistory } from 'ts/components/trade_history/trade_history';
 import { Container } from 'ts/components/ui/container';
 import { FlashMessage } from 'ts/components/ui/flash_message';
 import { Image } from 'ts/components/ui/image';
+import { PointerDirection } from 'ts/components/ui/pointer';
 import { Text } from 'ts/components/ui/text';
 import { Wallet } from 'ts/components/wallet/wallet';
 import { GenerateOrderForm } from 'ts/containers/generate_order_form';
@@ -107,6 +109,8 @@ const LEFT_COLUMN_WIDTH = 346;
 const MENU_PADDING_LEFT = 185;
 const LARGE_LAYOUT_MAX_WIDTH = 1200;
 const SIDE_PADDING = 20;
+const DOCUMENT_TITLE = '0x Portal';
+const DOCUMENT_DESCRIPTION = 'Learn about and trade on 0x Relayers';

 export class Portal extends React.Component<PortalProps, PortalState> {
    private _blockchain: Blockchain;
@@ -225,7 +229,8 @@ export class Portal extends React.Component<PortalProps, PortalState> {
                : TokenVisibility.TRACKED;
        return (
            <Container>
-                <DocumentTitle title="0x Portal" />
+                <MetaTags title={DOCUMENT_TITLE} description={DOCUMENT_DESCRIPTION} />
+                <DocumentTitle title={DOCUMENT_TITLE} />
                <TopBar
                    userAddress={this.props.userAddress}
                    networkId={this.props.networkId}
@@ -355,6 +360,9 @@ export class Portal extends React.Component<PortalProps, PortalState> {
                            onAddToken={this._onAddToken.bind(this)}
                            onRemoveToken={this._onRemoveToken.bind(this)}
                            refetchTokenStateAsync={this._refetchTokenStateAsync.bind(this)}
+                            toggleTooltipDirection={
+                                this.props.isPortalOnboardingShowing ? PointerDirection.Left : PointerDirection.Right
+                            }
                        />
                    </Container>
                    {!isMobile && <Container marginTop="8px">{this._renderStartOnboarding()}</Container>}
--- a/packages/website/ts/components/token_balances.tsx
+++ b/packages/website/ts/components/token_balances.tsx
@@ -24,7 +24,7 @@ import { SendButton } from 'ts/components/send_button';
 import { HelpTooltip } from 'ts/components/ui/help_tooltip';
 import { LifeCycleRaisedButton } from 'ts/components/ui/lifecycle_raised_button';
 import { TokenIcon } from 'ts/components/ui/token_icon';
-import { AllowanceToggle } from 'ts/containers/inputs/allowance_toggle';
+import { AllowanceStateToggle } from 'ts/containers/inputs/allowance_state_toggle';
 import { trackedTokenStorage } from 'ts/local_storage/tracked_token_storage';
 import { Dispatcher } from 'ts/redux/dispatcher';
 import {
@@ -372,14 +372,15 @@ export class TokenBalances extends React.Component<TokenBalancesProps, TokenBala
                    )}
                </TableRowColumn>
                <TableRowColumn>
-                    <AllowanceToggle
-                        blockchain={this.props.blockchain}
-                        token={token}
-                        tokenState={tokenState}
-                        onErrorOccurred={this._onErrorOccurred.bind(this)}
-                        isDisabled={!tokenState.isLoaded}
-                        refetchTokenStateAsync={this._refetchTokenStateAsync.bind(this, token.address)}
-                    />
+                    <div className="flex justify-center">
+                        <AllowanceStateToggle
+                            blockchain={this.props.blockchain}
+                            token={token}
+                            tokenState={tokenState}
+                            onErrorOccurred={this._onErrorOccurred.bind(this)}
+                            refetchTokenStateAsync={this._refetchTokenStateAsync.bind(this, token.address)}
+                        />
+                    </div>
                </TableRowColumn>
                {utils.isTestNetwork(this.props.networkId) && (
                    <TableRowColumn style={{ paddingLeft: actionPaddingX, paddingRight: actionPaddingX }}>
--- a/packages/website/ts/components/ui/allowance_state_view.tsx
+++ b/packages/website/ts/components/ui/allowance_state_view.tsx
@@ -0,0 +1,51 @@
+import { colors } from '@0xproject/react-shared';
+import * as React from 'react';
+import { Container } from 'ts/components/ui/container';
+import { Spinner } from 'ts/components/ui/spinner';
+
+export enum AllowanceState {
+    Locked,
+    Unlocked,
+    Loading,
+}
+
+export interface AllowanceStateViewProps {
+    allowanceState: AllowanceState;
+}
+
+export const AllowanceStateView: React.StatelessComponent<AllowanceStateViewProps> = ({ allowanceState }) => {
+    switch (allowanceState) {
+        case AllowanceState.Locked:
+            return renderLock();
+        case AllowanceState.Unlocked:
+            return renderCheck();
+        case AllowanceState.Loading:
+            return (
+                <Container position="relative" top="3px" left="5px">
+                    <Spinner size={18} strokeSize={2} />
+                </Container>
+            );
+        default:
+            return null;
+    }
+};
+
+const renderCheck = (color: string = colors.lightGreen) => (
+    <svg width="17" height="17" viewBox="0 0 17 17" fill="none" xmlns="http://www.w3.org/2000/svg">
+        <circle cx="8.5" cy="8.5" r="8.5" fill={color} />
+        <path
+            d="M2.5 4.5L1.79289 5.20711L2.5 5.91421L3.20711 5.20711L2.5 4.5ZM-0.707107 2.70711L1.79289 5.20711L3.20711 3.79289L0.707107 1.29289L-0.707107 2.70711ZM3.20711 5.20711L7.70711 0.707107L6.29289 -0.707107L1.79289 3.79289L3.20711 5.20711Z"
+            transform="translate(5 6.5)"
+            fill="white"
+        />
+    </svg>
+);
+
+const renderLock = () => (
+    <svg width="12" height="15" viewBox="0 0 12 15" fill="none" xmlns="http://www.w3.org/2000/svg">
+        <path
+            d="M6 0C3.51604 0 1.48688 2.0495 1.48688 4.55837V5.86581C0.664723 5.86581 -3.33647e-08 6.53719 -3.33647e-08 7.36759V13.3217C-3.33647e-08 14.1521 0.664723 14.8235 1.48688 14.8235H10.5131C11.3353 14.8235 12 14.1521 12 13.3217V7.36759C12 6.53719 11.3353 5.86581 10.5131 5.86581V4.55837C10.5131 2.0495 8.48396 0 6 0ZM8.93878 5.86581H3.06122V4.55837C3.06122 2.9329 4.37318 1.59013 6 1.59013C7.62682 1.59013 8.93878 2.9329 8.93878 4.55837V5.86581Z"
+            fill="black"
+        />
+    </svg>
+);
--- a/packages/website/ts/components/ui/container.tsx
+++ b/packages/website/ts/components/ui/container.tsx
@@ -32,8 +32,10 @@ export interface ContainerProps {
    bottom?: string;
    zIndex?: number;
    Tag?: ContainerTag;
+    cursor?: string;
    id?: string;
    onClick?: (event: React.MouseEvent<HTMLElement>) => void;
+    overflowX?: 'scroll' | 'hidden' | 'auto' | 'visible';
 }

 export const Container: React.StatelessComponent<ContainerProps> = props => {
--- a/packages/website/ts/components/ui/pointer.tsx
+++ b/packages/website/ts/components/ui/pointer.tsx
@@ -2,7 +2,12 @@ import { colors } from '@0xproject/react-shared';
 import * as React from 'react';
 import { styled } from 'ts/style/theme';

-export type PointerDirection = 'top' | 'right' | 'bottom' | 'left';
+export enum PointerDirection {
+    Top = 'top',
+    Right = 'right',
+    Bottom = 'bottom',
+    Left = 'left',
+}

 export interface PointerProps {
    className?: string;
--- a/packages/website/ts/components/ui/spinner.tsx
+++ b/packages/website/ts/components/ui/spinner.tsx
@@ -0,0 +1,54 @@
+import { colors } from '@0xproject/react-shared';
+import * as React from 'react';
+import { styled } from 'ts/style/theme';
+
+import { dash, rotate } from 'ts/style/keyframes';
+
+interface SpinnerSvgProps {
+    color: string;
+    size: number;
+    viewBox?: string;
+}
+
+const SpinnerSvg: React.StatelessComponent<SpinnerSvgProps> = props => <svg {...props} />;
+
+const StyledSpinner = styled(SpinnerSvg)`
+    animation: ${rotate} 3s linear infinite;
+    margin: ${props => `-${props.size / 2}px 0 0 -${props.size / 2}px`};
+    margin-top: ${props => `-${props.size / 2}px`};
+    margin-left: ${props => `-${props.size / 2}px`};
+    margin-bottom: 0px;
+    margin-right: 0px;
+    size: ${props => `${props.size}px`};
+    height: ${props => `${props.size}px`};
+
+    & .path {
+        stroke: ${props => props.color};
+        stroke-linecap: round;
+        animation: ${dash} 2.5s ease-in-out infinite;
+    }
+`;
+
+export interface SpinnerProps {
+    size?: number;
+    strokeSize?: number;
+    color?: string;
+}
+
+export const Spinner: React.StatelessComponent<SpinnerProps> = ({ size, strokeSize, color }) => {
+    const c = size / 2;
+    const r = c - strokeSize;
+    return (
+        <StyledSpinner color={color} size={size} viewBox={`0 0 ${size} ${size}`}>
+            <circle className="path" cx={c} cy={c} r={r} fill="none" strokeWidth={strokeSize} />
+        </StyledSpinner>
+    );
+};
+
+Spinner.defaultProps = {
+    size: 50,
+    color: colors.mediumBlue,
+    strokeSize: 4,
+};
+
+Spinner.displayName = 'Spinner';
--- a/packages/website/ts/components/ui/text.tsx
+++ b/packages/website/ts/components/ui/text.tsx
@@ -19,6 +19,7 @@ export interface TextProps {
    textDecorationLine?: string;
    onClick?: (event: React.MouseEvent<HTMLElement>) => void;
    hoverColor?: string;
+    noWrap?: boolean;
 }

 const PlainText: React.StatelessComponent<TextProps> = ({ children, className, onClick, Tag }) => (
@@ -39,6 +40,7 @@ export const Text = styled(PlainText)`
    ${props => (props.minHeight ? `min-height: ${props.minHeight}` : '')};
    ${props => (props.onClick ? 'cursor: pointer' : '')};
    transition: color 0.5s ease;
+    ${props => (props.noWrap ? 'white-space: nowrap' : '')};
    &:hover {
        ${props => (props.onClick ? `color: ${props.hoverColor || darken(0.3, props.fontColor)}` : '')};
    }
@@ -53,6 +55,7 @@ Text.defaultProps = {
    lineHeight: '1.5em',
    textDecorationLine: 'none',
    Tag: 'div',
+    noWrap: false,
 };

 Text.displayName = 'Text';
--- a/packages/website/ts/components/wallet/wallet.tsx
+++ b/packages/website/ts/components/wallet/wallet.tsx
@@ -14,6 +14,7 @@ import { DropDown, DropdownMouseEvent } from 'ts/components/ui/drop_down';
 import { IconButton } from 'ts/components/ui/icon_button';
 import { Identicon } from 'ts/components/ui/identicon';
 import { Island } from 'ts/components/ui/island';
+import { PointerDirection } from 'ts/components/ui/pointer';
 import {
    CopyAddressSimpleMenuItem,
    DifferentWalletSimpleMenuItem,
@@ -28,7 +29,7 @@ import { NullTokenRow } from 'ts/components/wallet/null_token_row';
 import { PlaceHolder } from 'ts/components/wallet/placeholder';
 import { StandardIconRow } from 'ts/components/wallet/standard_icon_row';
 import { WrapEtherItem } from 'ts/components/wallet/wrap_ether_item';
-import { AllowanceToggle } from 'ts/containers/inputs/allowance_toggle';
+import { AllowanceStateToggle } from 'ts/containers/inputs/allowance_state_toggle';
 import { Dispatcher } from 'ts/redux/dispatcher';
 import { colors } from 'ts/style/colors';
 import {
@@ -67,6 +68,7 @@ export interface WalletProps {
    onRemoveToken: () => void;
    refetchTokenStateAsync: (tokenAddress: string) => Promise<void>;
    style: React.CSSProperties;
+    toggleTooltipDirection?: PointerDirection;
 }

 interface WalletState {
@@ -74,14 +76,14 @@ interface WalletState {
    isHoveringSidebar: boolean;
 }

-interface AllowanceToggleConfig {
+interface AllowanceStateToggleConfig {
    token: Token;
    tokenState: TokenState;
 }

 interface AccessoryItemConfig {
    wrappedEtherDirection?: Side;
-    allowanceToggleConfig?: AllowanceToggleConfig;
+    allowanceStateToggleConfig?: AllowanceStateToggleConfig;
 }

 const ETHER_ICON_PATH = '/images/ether.png';
@@ -89,7 +91,8 @@ const ICON_DIMENSION = 28;
 const BODY_ITEM_KEY = 'BODY';
 const HEADER_ITEM_KEY = 'HEADER';
 const ETHER_ITEM_KEY = 'ETHER';
-const NO_ALLOWANCE_TOGGLE_SPACE_WIDTH = 56;
+const WRAP_ROW_ALLOWANCE_TOGGLE_WIDTH = 67;
+const ALLOWANCE_TOGGLE_WIDTH = 56;
 const PLACEHOLDER_COLOR = colors.grey300;
 const LOADING_ROWS_COUNT = 6;

@@ -338,7 +341,7 @@ export class Wallet extends React.Component<WalletProps, WalletState> {
        );
        const accessoryItemConfig: AccessoryItemConfig = {
            wrappedEtherDirection,
-            allowanceToggleConfig: {
+            allowanceStateToggleConfig: {
                token,
                tokenState,
            },
@@ -393,13 +396,15 @@ export class Wallet extends React.Component<WalletProps, WalletState> {
    }
    private _renderAccessoryItems(config: AccessoryItemConfig): React.ReactElement<{}> {
        const shouldShowWrappedEtherAction = !_.isUndefined(config.wrappedEtherDirection);
-        const shouldShowToggle = !_.isUndefined(config.allowanceToggleConfig);
+        const shouldShowToggle = !_.isUndefined(config.allowanceStateToggleConfig);
        // if we don't have a toggle, we still want some space to the right of the "wrap" button so that it aligns with
        // the "unwrap" button in the row below
-        const toggle = shouldShowToggle ? (
-            this._renderAllowanceToggle(config.allowanceToggleConfig)
-        ) : (
-            <div style={{ width: NO_ALLOWANCE_TOGGLE_SPACE_WIDTH }} />
+        const isWrapEtherRow = shouldShowWrappedEtherAction && config.wrappedEtherDirection === Side.Deposit;
+        const width = isWrapEtherRow ? WRAP_ROW_ALLOWANCE_TOGGLE_WIDTH : ALLOWANCE_TOGGLE_WIDTH;
+        const toggle = (
+            <Container className="flex justify-center" width={width}>
+                {shouldShowToggle && this._renderAllowanceToggle(config.allowanceStateToggleConfig)}
+            </Container>
        );
        return (
            <div className="flex items-center">
@@ -410,14 +415,14 @@ export class Wallet extends React.Component<WalletProps, WalletState> {
            </div>
        );
    }
-    private _renderAllowanceToggle(config: AllowanceToggleConfig): React.ReactNode {
+    private _renderAllowanceToggle(config: AllowanceStateToggleConfig): React.ReactNode {
        // TODO: Error handling
        return (
-            <AllowanceToggle
+            <AllowanceStateToggle
                blockchain={this.props.blockchain}
                token={config.token}
                tokenState={config.tokenState}
-                isDisabled={!config.tokenState.isLoaded}
+                tooltipDirection={this.props.toggleTooltipDirection}
                refetchTokenStateAsync={async () => this.props.refetchTokenStateAsync(config.token.address)}
            />
        );
--- a/packages/website/ts/containers/inputs/allowance_state_toggle.ts
+++ b/packages/website/ts/containers/inputs/allowance_state_toggle.ts
@@ -2,19 +2,20 @@ import * as React from 'react';
 import { connect } from 'react-redux';
 import { Dispatch } from 'redux';
 import { Blockchain } from 'ts/blockchain';
+import { PointerDirection } from 'ts/components/ui/pointer';
 import { State } from 'ts/redux/reducer';
 import { BalanceErrs, Token, TokenState } from 'ts/types';

-import { AllowanceToggle as AllowanceToggleComponent } from 'ts/components/inputs/allowance_toggle';
+import { AllowanceStateToggle as AllowanceStateToggleComponent } from 'ts/components/inputs/allowance_state_toggle';
 import { Dispatcher } from 'ts/redux/dispatcher';

-interface AllowanceToggleProps {
+interface AllowanceStateToggleProps {
    blockchain: Blockchain;
    onErrorOccurred?: (errType: BalanceErrs) => void;
    token: Token;
    tokenState: TokenState;
-    isDisabled?: boolean;
    refetchTokenStateAsync: () => Promise<void>;
+    tooltipDirection?: PointerDirection;
 }

 interface ConnectedState {
@@ -26,7 +27,7 @@ interface ConnectedDispatch {
    dispatcher: Dispatcher;
 }

-const mapStateToProps = (state: State, _ownProps: AllowanceToggleProps): ConnectedState => ({
+const mapStateToProps = (state: State, _ownProps: AllowanceStateToggleProps): ConnectedState => ({
    networkId: state.networkId,
    userAddress: state.userAddress,
 });
@@ -35,7 +36,7 @@ const mapDispatchTopProps = (dispatch: Dispatch<State>): ConnectedDispatch => ({
    dispatcher: new Dispatcher(dispatch),
 });

-export const AllowanceToggle: React.ComponentClass<AllowanceToggleProps> = connect(
+export const AllowanceStateToggle: React.ComponentClass<AllowanceStateToggleProps> = connect(
    mapStateToProps,
    mapDispatchTopProps,
-)(AllowanceToggleComponent);
+)(AllowanceStateToggleComponent);
--- a/packages/website/ts/index.tsx
+++ b/packages/website/ts/index.tsx
@@ -4,6 +4,7 @@ import { render } from 'react-dom';
 import { Provider } from 'react-redux';
 import { BrowserRouter as Router, Redirect, Route, Switch } from 'react-router-dom';
 import * as injectTapEventPlugin from 'react-tap-event-plugin';
+import { MetaTags } from 'ts/components/meta_tags';
 import { About } from 'ts/containers/about';
 import { FAQ } from 'ts/containers/faq';
 import { Jobs } from 'ts/containers/jobs';
@@ -65,73 +66,85 @@ const LazyEthereumTypesDocumentation = createLazyComponent('Documentation', asyn
    System.import<any>(/* webpackChunkName: "ethereumTypesDocs" */ 'ts/containers/ethereum_types_documentation'),
 );

-render(
-    <Router>
-        <div>
-            <MuiThemeProvider muiTheme={muiTheme}>
-                <Provider store={store}>
-                    <div>
-                        <Switch>
-                            <Route exact={true} path="/" component={Landing as any} />
-                            <Redirect from="/otc" to={`${WebsitePaths.Portal}`} />
-                            <Route path={WebsitePaths.Careers} component={Jobs as any} />
-                            <Route path={WebsitePaths.Portal} component={LazyPortal} />
-                            <Route path={WebsitePaths.FAQ} component={FAQ as any} />
-                            <Route path={WebsitePaths.About} component={About as any} />
-                            <Route path={WebsitePaths.Wiki} component={Wiki as any} />
-                            <Route path={`${WebsitePaths.ZeroExJs}/:version?`} component={LazyZeroExJSDocumentation} />
-                            <Route path={`${WebsitePaths.Connect}/:version?`} component={LazyConnectDocumentation} />
-                            <Route
-                                path={`${WebsitePaths.SolCompiler}/:version?`}
-                                component={LazySolCompilerDocumentation}
-                            />
-                            <Route path={`${WebsitePaths.SolCov}/:version?`} component={LazySolCovDocumentation} />
-                            <Route
-                                path={`${WebsitePaths.JSONSchemas}/:version?`}
-                                component={LazyJSONSchemasDocumentation}
-                            />
-                            <Route
-                                path={`${WebsitePaths.Subproviders}/:version?`}
-                                component={LazySubprovidersDocumentation}
-                            />
-                            <Route
-                                path={`${WebsitePaths.OrderUtils}/:version?`}
-                                component={LazyOrderUtilsDocumentation}
-                            />
-                            <Route
-                                path={`${WebsitePaths.Web3Wrapper}/:version?`}
-                                component={LazyWeb3WrapperDocumentation}
-                            />
-                            <Route
-                                path={`${WebsitePaths.SmartContracts}/:version?`}
-                                component={LazySmartContractsDocumentation}
-                            />
-                            <Route
-                                path={`${WebsitePaths.EthereumTypes}/:version?`}
-                                component={LazyEthereumTypesDocumentation}
-                            />
+const DOCUMENT_TITLE = '0x: The Protocol for Trading Tokens';
+const DOCUMENT_DESCRIPTION = 'An Open Protocol For Decentralized Exchange On The Ethereum Blockchain';

-                            {/* Legacy endpoints */}
-                            <Route
-                                path={`${WebsiteLegacyPaths.ZeroExJs}/:version?`}
-                                component={LazyZeroExJSDocumentation}
-                            />
-                            <Route
-                                path={`${WebsiteLegacyPaths.Web3Wrapper}/:version?`}
-                                component={LazyWeb3WrapperDocumentation}
-                            />
-                            <Route
-                                path={`${WebsiteLegacyPaths.Deployer}/:version?`}
-                                component={LazySolCompilerDocumentation}
-                            />
-                            <Route path={WebsiteLegacyPaths.Jobs} component={Jobs as any} />
-                            <Route path={`${WebsitePaths.Docs}`} component={LazyZeroExJSDocumentation} />
-                            <Route component={NotFound as any} />
-                        </Switch>
-                    </div>
-                </Provider>
-            </MuiThemeProvider>
-        </div>
-    </Router>,
+render(
+    <div>
+        <MetaTags title={DOCUMENT_TITLE} description={DOCUMENT_DESCRIPTION} />
+        <Router>
+            <div>
+                <MuiThemeProvider muiTheme={muiTheme}>
+                    <Provider store={store}>
+                        <div>
+                            <Switch>
+                                <Route exact={true} path="/" component={Landing as any} />
+                                <Redirect from="/otc" to={`${WebsitePaths.Portal}`} />
+                                <Route path={WebsitePaths.Careers} component={Jobs as any} />
+                                <Route path={WebsitePaths.Portal} component={LazyPortal} />
+                                <Route path={WebsitePaths.FAQ} component={FAQ as any} />
+                                <Route path={WebsitePaths.About} component={About as any} />
+                                <Route path={WebsitePaths.Wiki} component={Wiki as any} />
+                                <Route
+                                    path={`${WebsitePaths.ZeroExJs}/:version?`}
+                                    component={LazyZeroExJSDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.Connect}/:version?`}
+                                    component={LazyConnectDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.SolCompiler}/:version?`}
+                                    component={LazySolCompilerDocumentation}
+                                />
+                                <Route path={`${WebsitePaths.SolCov}/:version?`} component={LazySolCovDocumentation} />
+                                <Route
+                                    path={`${WebsitePaths.JSONSchemas}/:version?`}
+                                    component={LazyJSONSchemasDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.Subproviders}/:version?`}
+                                    component={LazySubprovidersDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.OrderUtils}/:version?`}
+                                    component={LazyOrderUtilsDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.Web3Wrapper}/:version?`}
+                                    component={LazyWeb3WrapperDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.SmartContracts}/:version?`}
+                                    component={LazySmartContractsDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsitePaths.EthereumTypes}/:version?`}
+                                    component={LazyEthereumTypesDocumentation}
+                                />
+
+                                {/* Legacy endpoints */}
+                                <Route
+                                    path={`${WebsiteLegacyPaths.ZeroExJs}/:version?`}
+                                    component={LazyZeroExJSDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsiteLegacyPaths.Web3Wrapper}/:version?`}
+                                    component={LazyWeb3WrapperDocumentation}
+                                />
+                                <Route
+                                    path={`${WebsiteLegacyPaths.Deployer}/:version?`}
+                                    component={LazySolCompilerDocumentation}
+                                />
+                                <Route path={WebsiteLegacyPaths.Jobs} component={Jobs as any} />
+                                <Route path={`${WebsitePaths.Docs}`} component={LazyZeroExJSDocumentation} />
+                                <Route component={NotFound as any} />
+                            </Switch>
+                        </div>
+                    </Provider>
+                </MuiThemeProvider>
+            </div>
+        </Router>
+    </div>,
    document.getElementById('app'),
 );
--- a/packages/website/ts/pages/jobs/jobs.tsx
+++ b/packages/website/ts/pages/jobs/jobs.tsx
@@ -4,7 +4,9 @@ import * as React from 'react';
 import * as DocumentTitle from 'react-document-title';

 import { Footer } from 'ts/components/footer';
+import { MetaTags } from 'ts/components/meta_tags';
 import { TopBar } from 'ts/components/top_bar/top_bar';
+import { Container } from 'ts/components/ui/container';
 import { Benefits } from 'ts/pages/jobs/benefits';
 import { Join0x } from 'ts/pages/jobs/join_0x';
 import { Mission } from 'ts/pages/jobs/mission';
@@ -16,6 +18,8 @@ import { utils } from 'ts/utils/utils';

 const OPEN_POSITIONS_HASH = 'positions';
 const THROTTLE_TIMEOUT = 100;
+const DOCUMENT_TITLE = 'Careers at 0x';
+const DOCUMENT_DESCRIPTION = 'Join 0x in creating a tokenized world where all value can flow freely';

 export interface JobsProps {
    location: Location;
@@ -39,8 +43,9 @@ export class Jobs extends React.Component<JobsProps, JobsState> {
    }
    public render(): React.ReactNode {
        return (
-            <div>
-                <DocumentTitle title="Careers at 0x" />
+            <Container overflowX="hidden">
+                <MetaTags title={DOCUMENT_TITLE} description={DOCUMENT_DESCRIPTION} />
+                <DocumentTitle title={DOCUMENT_TITLE} />
                <TopBar
                    blockchainIsLoaded={false}
                    location={this.props.location}
@@ -52,7 +57,7 @@ export class Jobs extends React.Component<JobsProps, JobsState> {
                <Benefits screenWidth={this.props.screenWidth} />
                <OpenPositions hash={OPEN_POSITIONS_HASH} screenWidth={this.props.screenWidth} />
                <Footer translate={this.props.translate} dispatcher={this.props.dispatcher} />
-            </div>
+            </Container>
        );
    }
    private _onJoin0xCallToActionClick(): void {
--- a/packages/website/ts/pages/jobs/join_0x.tsx
+++ b/packages/website/ts/pages/jobs/join_0x.tsx
@@ -20,10 +20,10 @@ export const Join0x = (props: Join0xProps) => (
            className="mx-auto inline-block align-middle py4"
            style={{ lineHeight: '44px', textAlign: 'center', position: 'relative' }}
        >
-            <Container className="sm-hide xs-hide md-hide" position="absolute" left="100%" marginLeft="80px">
+            <Container className="sm-hide xs-hide" position="absolute" left="100%" marginLeft="80px">
                <Image src="images/jobs/hero-dots-right.svg" width="400px" />
            </Container>
-            <Container className="sm-hide xs-hide md-hide" position="absolute" right="100%" marginRight="80px">
+            <Container className="sm-hide xs-hide" position="absolute" right="100%" marginRight="80px">
                <Image src="images/jobs/hero-dots-left.svg" width="400px" />
            </Container>
            <div className="h2 sm-center sm-pt3" style={{ fontFamily: 'Roboto Mono' }}>
--- a/packages/website/ts/style/keyframes.ts
+++ b/packages/website/ts/style/keyframes.ts
@@ -0,0 +1,22 @@
+import { keyframes } from 'ts/style/theme';
+
+export const rotate = keyframes`
+    100% {
+      transform: rotate(360deg);
+    }
+`;
+
+export const dash = keyframes`
+    0% {
+        stroke-dasharray: 1, 150;
+        stroke-dashoffset: 0;
+    }
+    50% {
+        stroke-dasharray: 90, 150;
+        stroke-dashoffset: -35;
+    }
+    100% {
+        stroke-dasharray: 90, 150;
+        stroke-dashoffset: -124;
+    }
+`;
--- a/yarn.lock
+++ b/yarn.lock
@@ -1002,6 +1002,10 @@
  version "0.4.30"
  resolved "https://registry.yarnpkg.com/@types/istanbul/-/istanbul-0.4.30.tgz#073159320ab3296b2cfeb481f756a1f8f4c9c8e4"

+"@types/js-combinatorics@^0.5.29":
+  version "0.5.29"
+  resolved "https://registry.yarnpkg.com/@types/js-combinatorics/-/js-combinatorics-0.5.29.tgz#47a7819a0b6925b6dc4bd2c2278a7e6329b29387"
+
 "@types/jsonschema@^1.1.1":
  version "1.1.1"
  resolved "https://registry.yarnpkg.com/@types/jsonschema/-/jsonschema-1.1.1.tgz#08703dfe074010e8e829123111594af731f57b1a"
@@ -1146,6 +1150,12 @@
    "@types/node" "*"
    "@types/react" "*"

+"@types/react-helmet@^5.0.6":
+  version "5.0.6"
+  resolved "https://registry.yarnpkg.com/@types/react-helmet/-/react-helmet-5.0.6.tgz#49607cbb72e1bb7dcefa9174cb591434d3b6f0af"
+  dependencies:
+    "@types/react" "*"
+
 "@types/react-redux@^4.4.37":
  version "4.4.47"
  resolved "https://registry.yarnpkg.com/@types/react-redux/-/react-redux-4.4.47.tgz#12af1677116e08d413fe2620d0a85560c8a0536e"
@@ -7628,6 +7638,10 @@ js-base64@^2.1.9:
  version "2.4.3"
  resolved "https://registry.yarnpkg.com/js-base64/-/js-base64-2.4.3.tgz#2e545ec2b0f2957f41356510205214e98fad6582"

+js-combinatorics@^0.5.3:
+  version "0.5.3"
+  resolved "https://registry.yarnpkg.com/js-combinatorics/-/js-combinatorics-0.5.3.tgz#5da5a1c4632ec59fdf8d49dccfe59ef088122b15"
+
 js-scrypt@^0.2.0:
  version "0.2.0"
  resolved "https://registry.yarnpkg.com/js-scrypt/-/js-scrypt-0.2.0.tgz#7a62b701b4616e70ad0cde544627aabb99d7fe39"
@@ -10981,6 +10995,15 @@ react-event-listener@^0.4.5:
    prop-types "^15.5.4"
    warning "^3.0.0"

+react-helmet@^5.2.0:
+  version "5.2.0"
+  resolved "https://registry.yarnpkg.com/react-helmet/-/react-helmet-5.2.0.tgz#a81811df21313a6d55c5f058c4aeba5d6f3d97a7"
+  dependencies:
+    deep-equal "^1.0.1"
+    object-assign "^4.1.1"
+    prop-types "^15.5.4"
+    react-side-effect "^1.1.0"
+
 react-highlight@0xproject/react-highlight:
  version "0.10.0"
  resolved "https://codeload.github.com/0xproject/react-highlight/tar.gz/83bbb4a09801abd341e2b9041cd884885a4a2098"
@@ -11088,7 +11111,7 @@ react-scroll@^1.5.2:
    lodash.throttle "^4.1.1"
    prop-types "^15.5.8"

-react-side-effect@^1.0.2:
+react-side-effect@^1.0.2, react-side-effect@^1.1.0:
  version "1.1.5"
  resolved "https://registry.yarnpkg.com/react-side-effect/-/react-side-effect-1.1.5.tgz#f26059e50ed9c626d91d661b9f3c8bb38cd0ff2d"
  dependencies: