Merge pull request #2657 from 0xProject/fix/ep/meta-transactions

EP: MetaTransactions fixes

contracts/exchange/test/dispatcher.ts

@@ -290,7 +290,7 @@ describe('AssetProxyDispatcher', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHash,
                 encodedAssetData,
-                nestedError.toString(),
+                nestedError.encode(),
             );
             const tx = assetProxyDispatcher
                 .dispatchTransferFrom(orderHash, encodedAssetData, makerAddress, takerAddress, amount)
@@ -313,7 +313,7 @@ describe('AssetProxyDispatcher', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 transferIndexAsBytes32,
                 assetDataB,
-                nestedError.toString(),
+                nestedError.encode(),
             );
             const tx = assetProxyDispatcher
                 .simulateDispatchTransferFromCalls(

contracts/exchange/test/signature_validator.ts

@@ -300,7 +300,7 @@ blockchainTests.resets('MixinSignatureValidator', env => {
                 hashHex,
                 validatorWallet.address,
                 signatureHex,
-                new StringRevertError(validatorWalletRevertReason).toString(),
+                new StringRevertError(validatorWalletRevertReason).encode(),
             );
             const tx = validateAsync(hashHex, validatorWallet.address, signatureHex, ValidatorWalletAction.Revert);
             return expect(tx).to.revertWith(expectedError);
@@ -562,7 +562,7 @@ blockchainTests.resets('MixinSignatureValidator', env => {
                 validatorWallet.address,
                 data,
                 signatureHex,
-                new StringRevertError(validatorWalletRevertReason).toString(),
+                new StringRevertError(validatorWalletRevertReason).encode(),
             );
             const tx = validateAsync(signedOrder, signatureHex, ValidatorWalletAction.Revert);
             return expect(tx).to.revertWith(expectedError);
@@ -693,7 +693,7 @@ blockchainTests.resets('MixinSignatureValidator', env => {
                 validatorWallet.address,
                 data,
                 signatureHex,
-                new StringRevertError(validatorWalletRevertReason).toString(),
+                new StringRevertError(validatorWalletRevertReason).encode(),
             );
             const tx = validateAsync(signedOrder, signatureHex, ValidatorWalletAction.Revert);
             return expect(tx).to.revertWith(expectedError);
@@ -916,7 +916,7 @@ blockchainTests.resets('MixinSignatureValidator', env => {
                 validatorWallet.address,
                 data,
                 signatureHex,
-                new StringRevertError(validatorWalletRevertReason).toString(),
+                new StringRevertError(validatorWalletRevertReason).encode(),
             );
             const tx = validateAsync(signedTransaction, signatureHex, ValidatorWalletAction.Revert);
             return expect(tx).to.revertWith(expectedError);
@@ -1041,7 +1041,7 @@ blockchainTests.resets('MixinSignatureValidator', env => {
                 validatorWallet.address,
                 data,
                 signatureHex,
-                new StringRevertError(validatorWalletRevertReason).toString(),
+                new StringRevertError(validatorWalletRevertReason).encode(),
             );
             const tx = validateAsync(signedTransaction, signatureHex, ValidatorWalletAction.Revert);
             return expect(tx).to.revertWith(expectedError);

contracts/exchange/test/transactions_unit_tests.ts

@@ -101,7 +101,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const executableError = new StringRevertError('EXECUTABLE_FAILED');
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 transactionHash,
-                executableError.toString(),
+                executableError.encode(),
             );
 
             // Call the `batchExecuteTransactions()` function and ensure that it reverts with the expected revert error.
@@ -123,7 +123,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const executableError = new StringRevertError('EXECUTABLE_FAILED');
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 transactionHash,
-                executableError.toString(),
+                executableError.encode(),
             );
 
             // Call the `batchExecuteTransactions()` function and ensure that it reverts with the expected revert error.
@@ -145,7 +145,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const executableError = new StringRevertError('EXECUTABLE_FAILED');
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 transactionHash,
-                executableError.toString(),
+                executableError.encode(),
             );
 
             // Call the `batchExecuteTransactions()` function and ensure that it reverts with the expected revert error.
@@ -280,7 +280,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const outerExecuteTransactionHash = transactionHashUtils.getTransactionHashHex(outerExecuteTransaction);
             const outerExpectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 outerExecuteTransactionHash,
-                innerExpectedError.toString(),
+                innerExpectedError.encode(),
             );
             const tx = transactionsContract
                 .batchExecuteTransactions([outerExecuteTransaction], [randomSignature()])
@@ -363,7 +363,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const errorData = new ExchangeRevertErrors.TransactionInvalidContextError(
                 innerTransactionHash,
                 accounts[0],
-            ).toString();
+            ).encode();
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(outerTransactionHash, errorData);
             const tx = transactionsContract
                 .executeTransaction(outerTransaction, validSignature)
@@ -385,7 +385,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const errorData = new ExchangeRevertErrors.TransactionInvalidContextError(
                 innerTransactionHash,
                 accounts[0],
-            ).toString();
+            ).encode();
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(outerTransactionHash, errorData);
             const tx = transactionsContract
                 .executeTransaction(outerTransaction, validSignature)
@@ -466,7 +466,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const executableError = new StringRevertError('EXECUTABLE_FAILED');
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 transactionHash,
-                executableError.toString(),
+                executableError.encode(),
             );
             const tx = transactionsContract
                 .executeTransaction(transaction, randomSignature())
@@ -486,7 +486,7 @@ blockchainTests.resets('Transaction Unit Tests', ({ provider, web3Wrapper, txDef
             const executableError = new StringRevertError('EXECUTABLE_FAILED');
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 transactionHash,
-                executableError.toString(),
+                executableError.encode(),
             );
             const tx = transactionsContract
                 .executeTransaction(transaction, validSignature)

contracts/integrations/CHANGELOG.json

@@ -5,6 +5,10 @@
             {
                 "note": "Update curveBridge tests",
                 "pr": 2633
+            },
+            {
+                "note": "Add EP RFQT + MTX tests",
+                "pr": 2692
             }
         ]
     },

contracts/integrations/package.json

@@ -101,6 +101,7 @@
         "@0x/contracts-multisig": "^4.1.7",
         "@0x/contracts-staking": "^2.0.14",
         "@0x/contracts-test-utils": "^5.3.4",
+        "@0x/contracts-zero-ex": "^0.2.0",
         "@0x/subproviders": "^6.1.1",
         "@0x/types": "^3.2.0",
         "@0x/typescript-typings": "^5.1.1",

contracts/integrations/test/exchange-proxy/mtx_test.ts

@@ -0,0 +1,426 @@
+import { ContractAddresses } from '@0x/contract-addresses';
+import { artifacts as erc20Artifacts, DummyERC20TokenContract } from '@0x/contracts-erc20';
+import { IExchangeContract } from '@0x/contracts-exchange';
+import { blockchainTests, constants, expect, getRandomPortion, verifyEventsFromLogs } from '@0x/contracts-test-utils';
+import {
+    artifacts as exchangeProxyArtifacts,
+    IZeroExContract,
+    LogMetadataTransformerContract,
+    signCallData,
+} from '@0x/contracts-zero-ex';
+import { migrateOnceAsync } from '@0x/migrations';
+import {
+    assetDataUtils,
+    encodeFillQuoteTransformerData,
+    encodePayTakerTransformerData,
+    ETH_TOKEN_ADDRESS,
+    FillQuoteTransformerSide,
+    findTransformerNonce,
+    signatureUtils,
+    SignedExchangeProxyMetaTransaction,
+} from '@0x/order-utils';
+import { AssetProxyId, Order, SignedOrder } from '@0x/types';
+import { BigNumber, hexUtils, ZeroExRevertErrors } from '@0x/utils';
+import * as ethjs from 'ethereumjs-util';
+
+const { MAX_UINT256, NULL_ADDRESS, NULL_BYTES, NULL_BYTES32, ZERO_AMOUNT } = constants;
+
+blockchainTests.resets('exchange proxy - meta-transactions', env => {
+    const quoteSignerKey = hexUtils.random();
+    const quoteSigner = hexUtils.toHex(ethjs.privateToAddress(ethjs.toBuffer(quoteSignerKey)));
+    let owner: string;
+    let relayer: string;
+    let maker: string;
+    let taker: string;
+    let flashWalletAddress: string;
+    let zeroEx: IZeroExContract;
+    let exchange: IExchangeContract;
+    let inputToken: DummyERC20TokenContract;
+    let outputToken: DummyERC20TokenContract;
+    let feeToken: DummyERC20TokenContract;
+    let addresses: ContractAddresses;
+    let protocolFee: BigNumber;
+    let metadataTransformer: LogMetadataTransformerContract;
+    const GAS_PRICE = new BigNumber('1e9');
+    const MAKER_BALANCE = new BigNumber('100e18');
+    const TAKER_BALANCE = new BigNumber('100e18');
+    const TAKER_FEE_BALANCE = new BigNumber('100e18');
+
+    before(async () => {
+        [, relayer, maker, taker] = await env.getAccountAddressesAsync();
+        addresses = await migrateOnceAsync(env.provider);
+        zeroEx = new IZeroExContract(addresses.exchangeProxy, env.provider, env.txDefaults, {
+            LogMetadataTransformer: LogMetadataTransformerContract.ABI(),
+            DummyERC20Token: DummyERC20TokenContract.ABI(),
+        });
+        exchange = new IExchangeContract(addresses.exchange, env.provider, env.txDefaults);
+        [inputToken, outputToken, feeToken] = await Promise.all(
+            [...new Array(3)].map(i =>
+                DummyERC20TokenContract.deployFrom0xArtifactAsync(
+                    erc20Artifacts.DummyERC20Token,
+                    env.provider,
+                    env.txDefaults,
+                    {},
+                    `DummyToken-${i}`,
+                    `TOK${i}`,
+                    new BigNumber(18),
+                    BigNumber.max(MAKER_BALANCE, TAKER_BALANCE),
+                ),
+            ),
+        );
+        // LogMetadataTransformer is not deployed in migrations.
+        metadataTransformer = await LogMetadataTransformerContract.deployFrom0xArtifactAsync(
+            exchangeProxyArtifacts.LogMetadataTransformer,
+            env.provider,
+            {
+                ...env.txDefaults,
+                from: addresses.exchangeProxyTransformerDeployer,
+            },
+            {},
+        );
+        owner = await zeroEx.owner().callAsync();
+        protocolFee = await exchange.protocolFeeMultiplier().callAsync();
+        flashWalletAddress = await zeroEx.getTransformWallet().callAsync();
+        const erc20Proxy = await exchange.getAssetProxy(AssetProxyId.ERC20).callAsync();
+        const allowanceTarget = await zeroEx.getAllowanceTarget().callAsync();
+        await outputToken.mint(MAKER_BALANCE).awaitTransactionSuccessAsync({ from: maker });
+        await inputToken.mint(TAKER_BALANCE).awaitTransactionSuccessAsync({ from: taker });
+        await feeToken.mint(TAKER_FEE_BALANCE).awaitTransactionSuccessAsync({ from: taker });
+        await outputToken.approve(erc20Proxy, MAX_UINT256).awaitTransactionSuccessAsync({ from: maker });
+        await inputToken.approve(allowanceTarget, MAX_UINT256).awaitTransactionSuccessAsync({ from: taker });
+        await feeToken.approve(allowanceTarget, MAX_UINT256).awaitTransactionSuccessAsync({ from: taker });
+        await zeroEx.setQuoteSigner(quoteSigner).awaitTransactionSuccessAsync({ from: owner });
+    });
+
+    interface Transformation {
+        deploymentNonce: number;
+        data: string;
+    }
+
+    interface SwapInfo {
+        inputTokenAddress: string;
+        outputTokenAddress: string;
+        inputTokenAmount: BigNumber;
+        minOutputTokenAmount: BigNumber;
+        transformations: Transformation[];
+        orders: SignedOrder[];
+    }
+
+    async function generateSwapAsync(orderFields: Partial<Order> = {}, isRfqt: boolean = false): Promise<SwapInfo> {
+        const order = await signatureUtils.ecSignTypedDataOrderAsync(
+            env.provider,
+            {
+                chainId: 1337,
+                exchangeAddress: exchange.address,
+                expirationTimeSeconds: new BigNumber(Date.now()),
+                salt: new BigNumber(hexUtils.random()),
+                feeRecipientAddress: NULL_ADDRESS,
+                senderAddress: NULL_ADDRESS,
+                takerAddress: isRfqt ? flashWalletAddress : NULL_ADDRESS,
+                makerAddress: maker,
+                makerAssetData: assetDataUtils.encodeERC20AssetData(outputToken.address),
+                takerAssetData: assetDataUtils.encodeERC20AssetData(inputToken.address),
+                makerFeeAssetData: NULL_BYTES,
+                takerFeeAssetData: NULL_BYTES,
+                takerAssetAmount: getRandomPortion(TAKER_BALANCE),
+                makerAssetAmount: getRandomPortion(MAKER_BALANCE),
+                makerFee: ZERO_AMOUNT,
+                takerFee: ZERO_AMOUNT,
+                ...orderFields,
+            },
+            maker,
+        );
+        const transformations = [
+            {
+                deploymentNonce: findTransformerNonce(
+                    addresses.transformers.fillQuoteTransformer,
+                    addresses.exchangeProxyTransformerDeployer,
+                ),
+                data: encodeFillQuoteTransformerData({
+                    orders: [order],
+                    signatures: [order.signature],
+                    buyToken: outputToken.address,
+                    sellToken: inputToken.address,
+                    fillAmount: order.takerAssetAmount,
+                    maxOrderFillAmounts: [],
+                    refundReceiver: hexUtils.leftPad(2, 20), // Send refund to sender.
+                    rfqtTakerAddress: isRfqt ? taker : NULL_ADDRESS,
+                    side: FillQuoteTransformerSide.Sell,
+                }),
+            },
+            {
+                deploymentNonce: findTransformerNonce(
+                    addresses.transformers.payTakerTransformer,
+                    addresses.exchangeProxyTransformerDeployer,
+                ),
+                data: encodePayTakerTransformerData({
+                    tokens: [inputToken.address, outputToken.address, ETH_TOKEN_ADDRESS],
+                    amounts: [MAX_UINT256, MAX_UINT256, MAX_UINT256],
+                }),
+            },
+            {
+                deploymentNonce: findTransformerNonce(
+                    metadataTransformer.address,
+                    addresses.exchangeProxyTransformerDeployer,
+                ),
+                data: NULL_BYTES,
+            },
+        ];
+        return {
+            transformations,
+            orders: [order],
+            inputTokenAddress: inputToken.address,
+            outputTokenAddress: outputToken.address,
+            inputTokenAmount: order.takerAssetAmount,
+            minOutputTokenAmount: order.makerAssetAmount,
+        };
+    }
+
+    function getSwapData(swap: SwapInfo): string {
+        return zeroEx
+            .transformERC20(
+                swap.inputTokenAddress,
+                swap.outputTokenAddress,
+                swap.inputTokenAmount,
+                swap.minOutputTokenAmount,
+                swap.transformations,
+            )
+            .getABIEncodedTransactionData();
+    }
+
+    function getSignedSwapData(swap: SwapInfo, signerKey?: string): string {
+        return signCallData(
+            zeroEx
+                .transformERC20(
+                    swap.inputTokenAddress,
+                    swap.outputTokenAddress,
+                    swap.inputTokenAmount,
+                    swap.minOutputTokenAmount,
+                    swap.transformations,
+                )
+                .getABIEncodedTransactionData(),
+            signerKey ? signerKey : quoteSignerKey,
+        );
+    }
+
+    async function createMetaTransactionAsync(
+        data: string,
+        value: BigNumber,
+        fee?: BigNumber | number,
+    ): Promise<SignedExchangeProxyMetaTransaction> {
+        return signatureUtils.ecSignTypedDataExchangeProxyMetaTransactionAsync(
+            env.provider,
+            {
+                value,
+                signer: taker,
+                sender: relayer,
+                minGasPrice: GAS_PRICE,
+                maxGasPrice: GAS_PRICE,
+                expirationTimeSeconds: new BigNumber(Math.floor(Date.now() / 1000) + 60),
+                salt: new BigNumber(hexUtils.random()),
+                callData: data,
+                feeToken: feeToken.address,
+                feeAmount: fee !== undefined ? new BigNumber(fee) : getRandomPortion(TAKER_FEE_BALANCE),
+                domain: {
+                    chainId: 1,
+                    name: 'ZeroEx',
+                    version: '1.0.0',
+                    verifyingContract: zeroEx.address,
+                },
+            },
+            taker,
+        );
+    }
+
+    it('can call `transformERC20()` with signed calldata and no relayer fee', async () => {
+        const swap = await generateSwapAsync();
+        const callDataHash = hexUtils.hash(getSwapData(swap));
+        const signedSwapData = getSignedSwapData(swap);
+        const _protocolFee = protocolFee.times(GAS_PRICE).times(swap.orders.length + 1); // Pay a little more fee than needed.
+        const mtx = await createMetaTransactionAsync(signedSwapData, _protocolFee, 0);
+        const relayerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(relayer);
+        const receipt = await zeroEx
+            .executeMetaTransaction(mtx, mtx.signature)
+            .awaitTransactionSuccessAsync({ from: relayer, value: mtx.value, gasPrice: GAS_PRICE });
+        const relayerEthRefund = relayerEthBalanceBefore
+            .minus(await env.web3Wrapper.getBalanceInWeiAsync(relayer))
+            .minus(GAS_PRICE.times(receipt.gasUsed));
+        // Ensure the relayer got back the unused protocol fees.
+        expect(relayerEthRefund).to.bignumber.eq(protocolFee.times(GAS_PRICE));
+        // Ensure the relayer got paid no mtx fees.
+        expect(await feeToken.balanceOf(relayer).callAsync()).to.bignumber.eq(0);
+        // Ensure the taker got output tokens.
+        expect(await outputToken.balanceOf(taker).callAsync()).to.bignumber.eq(swap.minOutputTokenAmount);
+        // Ensure the maker got input tokens.
+        expect(await inputToken.balanceOf(maker).callAsync()).to.bignumber.eq(swap.inputTokenAmount);
+        // Check events.
+        verifyEventsFromLogs(
+            receipt.logs,
+            [
+                {
+                    taker,
+                    callDataHash,
+                    sender: zeroEx.address,
+                    data: NULL_BYTES,
+                },
+            ],
+            'TransformerMetadata',
+        );
+    });
+
+    it('can call `transformERC20()` with signed calldata and a relayer fee', async () => {
+        const swap = await generateSwapAsync();
+        const callDataHash = hexUtils.hash(getSwapData(swap));
+        const signedSwapData = getSignedSwapData(swap);
+        const _protocolFee = protocolFee.times(GAS_PRICE).times(swap.orders.length + 1); // Pay a little more fee than needed.
+        const mtx = await createMetaTransactionAsync(signedSwapData, _protocolFee);
+        const relayerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(relayer);
+        const receipt = await zeroEx
+            .executeMetaTransaction(mtx, mtx.signature)
+            .awaitTransactionSuccessAsync({ from: relayer, value: mtx.value, gasPrice: GAS_PRICE });
+        const relayerEthRefund = relayerEthBalanceBefore
+            .minus(await env.web3Wrapper.getBalanceInWeiAsync(relayer))
+            .minus(GAS_PRICE.times(receipt.gasUsed));
+        // Ensure the relayer got back the unused protocol fees.
+        expect(relayerEthRefund).to.bignumber.eq(protocolFee.times(GAS_PRICE));
+        // Ensure the relayer got paid mtx fees.
+        expect(await feeToken.balanceOf(relayer).callAsync()).to.bignumber.eq(mtx.feeAmount);
+        // Ensure the taker got output tokens.
+        expect(await outputToken.balanceOf(taker).callAsync()).to.bignumber.eq(swap.minOutputTokenAmount);
+        // Ensure the maker got input tokens.
+        expect(await inputToken.balanceOf(maker).callAsync()).to.bignumber.eq(swap.inputTokenAmount);
+        // Check events.
+        verifyEventsFromLogs(
+            receipt.logs,
+            [
+                {
+                    taker,
+                    callDataHash,
+                    sender: zeroEx.address,
+                    data: NULL_BYTES,
+                },
+            ],
+            'TransformerMetadata',
+        );
+    });
+
+    it('can call `transformERC20()` with wrongly signed calldata and a relayer fee', async () => {
+        const swap = await generateSwapAsync();
+        const signedSwapData = getSignedSwapData(swap, hexUtils.random());
+        const _protocolFee = protocolFee.times(GAS_PRICE).times(swap.orders.length + 1); // Pay a little more fee than needed.
+        const mtx = await createMetaTransactionAsync(signedSwapData, _protocolFee);
+        const relayerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(relayer);
+        const receipt = await zeroEx
+            .executeMetaTransaction(mtx, mtx.signature)
+            .awaitTransactionSuccessAsync({ from: relayer, value: mtx.value, gasPrice: GAS_PRICE });
+        const relayerEthRefund = relayerEthBalanceBefore
+            .minus(await env.web3Wrapper.getBalanceInWeiAsync(relayer))
+            .minus(GAS_PRICE.times(receipt.gasUsed));
+        // Ensure the relayer got back the unused protocol fees.
+        expect(relayerEthRefund).to.bignumber.eq(protocolFee.times(GAS_PRICE));
+        // Ensure the relayer got paid mtx fees.
+        expect(await feeToken.balanceOf(relayer).callAsync()).to.bignumber.eq(mtx.feeAmount);
+        // Ensure the taker got output tokens.
+        expect(await outputToken.balanceOf(taker).callAsync()).to.bignumber.eq(swap.minOutputTokenAmount);
+        // Ensure the maker got input tokens.
+        expect(await inputToken.balanceOf(maker).callAsync()).to.bignumber.eq(swap.inputTokenAmount);
+        // Check events.
+        verifyEventsFromLogs(
+            receipt.logs,
+            [
+                {
+                    taker,
+                    // Only signed calldata should have a nonzero hash.
+                    callDataHash: NULL_BYTES32,
+                    sender: zeroEx.address,
+                    data: NULL_BYTES,
+                },
+            ],
+            'TransformerMetadata',
+        );
+    });
+
+    it('`transformERC20()` can fill RFQT order if calldata is signed', async () => {
+        const swap = await generateSwapAsync({}, true);
+        const callDataHash = hexUtils.hash(getSwapData(swap));
+        const signedSwapData = getSignedSwapData(swap);
+        const _protocolFee = protocolFee.times(GAS_PRICE).times(swap.orders.length + 1); // Pay a little more fee than needed.
+        const mtx = await createMetaTransactionAsync(signedSwapData, _protocolFee, 0);
+        const relayerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(relayer);
+        const receipt = await zeroEx
+            .executeMetaTransaction(mtx, mtx.signature)
+            .awaitTransactionSuccessAsync({ from: relayer, value: mtx.value, gasPrice: GAS_PRICE });
+        const relayerEthRefund = relayerEthBalanceBefore
+            .minus(await env.web3Wrapper.getBalanceInWeiAsync(relayer))
+            .minus(GAS_PRICE.times(receipt.gasUsed));
+        // Ensure the relayer got back the unused protocol fees.
+        expect(relayerEthRefund).to.bignumber.eq(protocolFee.times(GAS_PRICE));
+        // Ensure the relayer got paid no mtx fees.
+        expect(await feeToken.balanceOf(relayer).callAsync()).to.bignumber.eq(0);
+        // Ensure the taker got output tokens.
+        expect(await outputToken.balanceOf(taker).callAsync()).to.bignumber.eq(swap.minOutputTokenAmount);
+        // Ensure the maker got input tokens.
+        expect(await inputToken.balanceOf(maker).callAsync()).to.bignumber.eq(swap.inputTokenAmount);
+        // Check events.
+        verifyEventsFromLogs(
+            receipt.logs,
+            [
+                {
+                    taker,
+                    callDataHash,
+                    sender: zeroEx.address,
+                    data: NULL_BYTES,
+                },
+            ],
+            'TransformerMetadata',
+        );
+    });
+
+    it('`transformERC20()` can fill RFQT order if calldata is not signed but no quote signer configured', async () => {
+        const swap = await generateSwapAsync({}, true);
+        const callData = getSwapData(swap);
+        const callDataHash = hexUtils.hash(callData);
+        const _protocolFee = protocolFee.times(GAS_PRICE).times(swap.orders.length + 1); // Pay a little more fee than needed.
+        const mtx = await createMetaTransactionAsync(callData, _protocolFee, 0);
+        const relayerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(relayer);
+        await zeroEx.setQuoteSigner(NULL_ADDRESS).awaitTransactionSuccessAsync({ from: owner });
+        const receipt = await zeroEx
+            .executeMetaTransaction(mtx, mtx.signature)
+            .awaitTransactionSuccessAsync({ from: relayer, value: mtx.value, gasPrice: GAS_PRICE });
+        const relayerEthRefund = relayerEthBalanceBefore
+            .minus(await env.web3Wrapper.getBalanceInWeiAsync(relayer))
+            .minus(GAS_PRICE.times(receipt.gasUsed));
+        // Ensure the relayer got back the unused protocol fees.
+        expect(relayerEthRefund).to.bignumber.eq(protocolFee.times(GAS_PRICE));
+        // Ensure the relayer got paid no mtx fees.
+        expect(await feeToken.balanceOf(relayer).callAsync()).to.bignumber.eq(0);
+        // Ensure the taker got output tokens.
+        expect(await outputToken.balanceOf(taker).callAsync()).to.bignumber.eq(swap.minOutputTokenAmount);
+        // Ensure the maker got input tokens.
+        expect(await inputToken.balanceOf(maker).callAsync()).to.bignumber.eq(swap.inputTokenAmount);
+        // Check events.
+        verifyEventsFromLogs(
+            receipt.logs,
+            [
+                {
+                    taker,
+                    callDataHash,
+                    sender: zeroEx.address,
+                    data: NULL_BYTES,
+                },
+            ],
+            'TransformerMetadata',
+        );
+    });
+
+    it('`transformERC20()` cannot fill RFQT order if calldata is not signed', async () => {
+        const swap = await generateSwapAsync({}, true);
+        const callData = getSwapData(swap);
+        const _protocolFee = protocolFee.times(GAS_PRICE).times(swap.orders.length + 1); // Pay a little more fee than needed.
+        const mtx = await createMetaTransactionAsync(callData, _protocolFee, 0);
+        const tx = zeroEx
+            .executeMetaTransaction(mtx, mtx.signature)
+            .awaitTransactionSuccessAsync({ from: relayer, value: mtx.value, gasPrice: GAS_PRICE });
+        return expect(tx).to.revertWith(new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError());
+    });
+});

contracts/integrations/test/exchange/core_test.ts

@@ -558,7 +558,7 @@ blockchainTests.resets('Exchange core', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashHex,
                 signedOrder.makerAssetData,
-                new StringRevertError(RevertReason.TransferFailed).toString(),
+                new StringRevertError(RevertReason.TransferFailed).encode(),
             );
             const tx = exchange
                 .fillOrder(signedOrder, takerAssetFillAmount, signedOrder.signature)
@@ -587,7 +587,7 @@ blockchainTests.resets('Exchange core', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashHex,
                 signedOrder.takerAssetData,
-                new StringRevertError(RevertReason.TransferFailed).toString(),
+                new StringRevertError(RevertReason.TransferFailed).encode(),
             );
             const tx = exchange
                 .fillOrder(signedOrder, takerAssetFillAmount, signedOrder.signature)
@@ -616,7 +616,7 @@ blockchainTests.resets('Exchange core', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashHex,
                 signedOrder.makerAssetData,
-                new StringRevertError(RevertReason.InvalidAmount).toString(),
+                new StringRevertError(RevertReason.InvalidAmount).encode(),
             );
             const tx = exchange
                 .fillOrder(signedOrder, takerAssetFillAmount, signedOrder.signature)
@@ -645,7 +645,7 @@ blockchainTests.resets('Exchange core', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashHex,
                 signedOrder.takerAssetData,
-                new StringRevertError(RevertReason.InvalidAmount).toString(),
+                new StringRevertError(RevertReason.InvalidAmount).encode(),
             );
             const tx = exchange
                 .fillOrder(signedOrder, takerAssetFillAmount, signedOrder.signature)
@@ -980,7 +980,7 @@ blockchainTests.resets('Exchange core', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashHex,
                 assetData,
-                new StringRevertError(RevertReason.TargetNotEven).toString(),
+                new StringRevertError(RevertReason.TargetNotEven).encode(),
             );
             const tx = exchange
                 .fillOrder(signedOrder, signedOrder.takerAssetAmount, signedOrder.signature)
@@ -1015,7 +1015,7 @@ blockchainTests.resets('Exchange core', () => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashHex,
                 assetData,
-                new StringRevertError(RevertReason.TargetNotEven).toString(),
+                new StringRevertError(RevertReason.TargetNotEven).encode(),
             );
             const tx = exchange
                 .fillOrder(signedOrder, signedOrder.takerAssetAmount, signedOrder.signature)

contracts/integrations/test/exchange/fill_dydx_order_test.ts

@@ -278,7 +278,7 @@ blockchainTests.resets('Exchange fills dydx orders', env => {
             } catch (e) {
                 assetProxyError = decodeThrownErrorAsRevertError(e).values.errorData;
             }
-            expect(assetProxyError).to.deep.equal(new StringRevertError(expectedAssetProxyError.toString()));
+            expect(assetProxyError).to.deep.equal(new StringRevertError(expectedAssetProxyError.encode()));
         });
     });
 });

contracts/integrations/test/exchange/transaction_protocol_fee_test.ts

@@ -121,7 +121,7 @@ blockchainTests.resets('Transaction <> protocol fee integration tests', env => {
             maker.address,
             wethless.address,
             '0x',
-        ).toString();
+        ).encode();
         return new ExchangeRevertErrors.TransactionExecutionError(
             transactionHashUtils.getTransactionHashHex(failedTransaction),
             nestedError,
@@ -252,7 +252,7 @@ blockchainTests.resets('Transaction <> protocol fee integration tests', env => {
                     .awaitTransactionSuccessAsync({ from: alice.address, value: REFUND_AMOUNT });
                 const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                     transactionHashUtils.getTransactionHashHex(recursiveTransaction),
-                    protocolFeeError(order, transaction).toString(),
+                    protocolFeeError(order, transaction).encode(),
                 );
                 return expect(tx).to.revertWith(expectedError);
             });

contracts/integrations/test/exchange/transaction_test.ts

@@ -280,7 +280,7 @@ blockchainTests.resets('Transaction integration tests', env => {
                     const noReentrancyError = new ExchangeRevertErrors.TransactionInvalidContextError(
                         transactionHashHex,
                         transaction.signerAddress,
-                    ).toString();
+                    ).encode();
                     const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                         recursiveTransactionHashHex,
                         noReentrancyError,
@@ -330,7 +330,7 @@ blockchainTests.resets('Transaction integration tests', env => {
                             orderHashUtils.getOrderHashHex(order),
                             order.makerAddress,
                             order.signature,
-                        ).toString();
+                        ).encode();
                         const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                             transactionHashHex,
                             nestedError,
@@ -353,7 +353,7 @@ blockchainTests.resets('Transaction integration tests', env => {
                     ExchangeRevertErrors.ExchangeContextErrorCodes.InvalidMaker,
                     orderHashUtils.getOrderHashHex(order),
                     takers[0].address,
-                ).toString();
+                ).encode();
                 const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                     transactionHashHex,
                     nestedError,
@@ -403,7 +403,7 @@ blockchainTests.resets('Transaction integration tests', env => {
                     ExchangeRevertErrors.ExchangeContextErrorCodes.InvalidMaker,
                     orderHashUtils.getOrderHashHex(orders[0]),
                     takers[0].address,
-                ).toString();
+                ).encode();
                 const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                     transactionHashHex,
                     nestedError,
@@ -771,7 +771,7 @@ blockchainTests.resets('Transaction integration tests', env => {
             const nestedError = new ExchangeRevertErrors.OrderStatusError(
                 orderHashUtils.getOrderHashHex(order),
                 OrderStatus.Cancelled,
-            ).toString();
+            ).encode();
             const expectedError = new ExchangeRevertErrors.TransactionExecutionError(
                 transactionHashUtils.getTransactionHashHex(transaction2),
                 nestedError,

contracts/integrations/test/stop-limit/chainlink_stop_limit_test.ts

@@ -123,7 +123,7 @@ blockchainTests.resets('Chainlink stop-limit order tests', env => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashUtils.getOrderHashHex(order),
                 order.makerAssetData,
-                new StringRevertError('ChainlinkStopLimit/OUT_OF_PRICE_RANGE').toString(),
+                new StringRevertError('ChainlinkStopLimit/OUT_OF_PRICE_RANGE').encode(),
             );
             return expect(tx).to.revertWith(expectedError);
         });
@@ -133,7 +133,7 @@ blockchainTests.resets('Chainlink stop-limit order tests', env => {
             const expectedError = new ExchangeRevertErrors.AssetProxyTransferError(
                 orderHashUtils.getOrderHashHex(order),
                 order.makerAssetData,
-                new StringRevertError('ChainlinkStopLimit/OUT_OF_PRICE_RANGE').toString(),
+                new StringRevertError('ChainlinkStopLimit/OUT_OF_PRICE_RANGE').encode(),
             );
             return expect(tx).to.revertWith(expectedError);
         });

contracts/zero-ex/CHANGELOG.json

@@ -1,4 +1,57 @@
 [
+    {
+        "version": "0.3.0",
+        "changes": [
+            {
+                "note": "Internal audit fixes",
+                "pr": 2657
+            },
+            {
+                "note": "Add refund mechanism to meta-transactions",
+                "pr": 2657
+            },
+            {
+                "note": "Pass sender address to transformers",
+                "pr": 2657
+            },
+            {
+                "note": "Refund unused protocol fees to `refundReceiver` in FQT",
+                "pr": 2657
+            },
+            {
+                "note": "Fix `TransformerDeployer.kill()` calling the wrong `die()` interface.",
+                "pr": 2624
+            },
+            {
+                "note": "Address CD post-audit feedback",
+                "pr": 2657
+            },
+            {
+                "note": "Add `LogMetadataTransformer`",
+                "pr": 2657
+            },
+            {
+                "note": "Rename all feature contracts to have `Feature` suffix",
+                "pr": 2657
+            },
+            {
+                "note": "Return `IZeroExContract` in `fullMigrateAsync()`",
+                "pr": 2657
+            },
+            {
+                "note": "Add taker address enforcement to RFQT orders in FQT",
+                "pr": 2692
+            },
+            {
+                "note": "All calldata is valid if quote signer is unset in `TransformERC20`",
+                "pr": 2692
+            },
+            {
+                "note": "Add updated Kyber and Mooniswap rollup to FQT",
+                "pr": 2692
+            }
+        ]
+    },
     {
         "version": "0.2.0",
         "changes": [

contracts/zero-ex/contracts/src/IZeroEx.sol

@@ -19,22 +19,22 @@
 pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
-import "./features/IOwnable.sol";
+import "./features/IOwnableFeature.sol";
-import "./features/ISimpleFunctionRegistry.sol";
+import "./features/ISimpleFunctionRegistryFeature.sol";
-import "./features/ITokenSpender.sol";
+import "./features/ITokenSpenderFeature.sol";
-import "./features/ISignatureValidator.sol";
+import "./features/ISignatureValidatorFeature.sol";
-import "./features/ITransformERC20.sol";
+import "./features/ITransformERC20Feature.sol";
-import "./features/IMetaTransactions.sol";
+import "./features/IMetaTransactionsFeature.sol";
 
 
 /// @dev Interface for a fully featured Exchange Proxy.
 interface IZeroEx is
-    IOwnable,
+    IOwnableFeature,
-    ISimpleFunctionRegistry,
+    ISimpleFunctionRegistryFeature,
-    ITokenSpender,
+    ITokenSpenderFeature,
-    ISignatureValidator,
+    ISignatureValidatorFeature,
-    ITransformERC20,
+    ITransformERC20Feature,
-    IMetaTransactions
+    IMetaTransactionsFeature
 {
     // solhint-disable state-visibility
 

contracts/zero-ex/contracts/src/ZeroEx.sol

@@ -21,7 +21,7 @@ pragma experimental ABIEncoderV2;
 
 import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
 import "./migrations/LibBootstrap.sol";
-import "./features/Bootstrap.sol";
+import "./features/BootstrapFeature.sol";
 import "./storage/LibProxyStorage.sol";
 import "./errors/LibProxyRichErrors.sol";
 
@@ -32,14 +32,14 @@ contract ZeroEx {
     // solhint-disable separate-by-one-line-in-contract,indent,var-name-mixedcase
     using LibBytesV06 for bytes;
 
-    /// @dev Construct this contract and register the `Bootstrap` feature.
+    /// @dev Construct this contract and register the `BootstrapFeature` feature.
     ///      After constructing this contract, `bootstrap()` should be called
     ///      by `bootstrap()` to seed the initial feature set.
     /// @param bootstrapper Who can call `bootstrap()`.
     constructor(address bootstrapper) public {
         // Temporarily create and register the bootstrap feature.
         // It will deregister itself after `bootstrap()` has been called.
-        Bootstrap bootstrap = new Bootstrap(bootstrapper);
+        BootstrapFeature bootstrap = new BootstrapFeature(bootstrapper);
         LibProxyStorage.getStorage().impls[bootstrap.bootstrap.selector] =
             address(bootstrap);
     }

contracts/zero-ex/contracts/src/errors/LibCommonRichErrors.sol

@@ -34,13 +34,15 @@ library LibCommonRichErrors {
         );
     }
 
-    function IllegalReentrancyError()
+    function IllegalReentrancyError(bytes4 selector, uint256 reentrancyFlags)
         internal
         pure
         returns (bytes memory)
     {
         return abi.encodeWithSelector(
-            bytes4(keccak256("IllegalReentrancyError()"))
+            bytes4(keccak256("IllegalReentrancyError(bytes4,uint256)")),
+            selector,
+            reentrancyFlags
         );
     }
 }

contracts/zero-ex/contracts/src/external/TransformerDeployer.sol

@@ -24,7 +24,7 @@ import "@0x/contracts-utils/contracts/src/v06/AuthorizableV06.sol";
 
 /// @dev A contract with a `die()` function.
 interface IKillable {
-    function die() external;
+    function die(address payable ethRecipient) external;
 }
 
 /// @dev Deployer contract for ERC20 transformers.
@@ -48,9 +48,9 @@ contract TransformerDeployer is
     mapping (address => uint256) public toDeploymentNonce;
 
     /// @dev Create this contract and register authorities.
-    constructor(address[] memory authorities) public {
+    constructor(address[] memory initialAuthorities) public {
-        for (uint256 i = 0; i < authorities.length; ++i) {
+        for (uint256 i = 0; i < initialAuthorities.length; ++i) {
-            _addAuthorizedAddress(authorities[i]);
+            _addAuthorizedAddress(initialAuthorities[i]);
         }
     }
 
@@ -67,16 +67,19 @@ contract TransformerDeployer is
         assembly {
             deployedAddress := create(callvalue(), add(bytecode, 32), mload(bytecode))
         }
+        require(deployedAddress != address(0), 'TransformerDeployer/DEPLOY_FAILED');
         toDeploymentNonce[deployedAddress] = deploymentNonce;
         emit Deployed(deployedAddress, deploymentNonce, msg.sender);
     }
 
     /// @dev Call `die()` on a contract. Only callable by an authority.
-    function kill(IKillable target)
+    /// @param target The target contract to call `die()` on.
+    /// @param ethRecipient The Recipient of any ETH locked in `target`.
+    function kill(IKillable target, address payable ethRecipient)
         public
         onlyAuthorized
     {
-        target.die();
+        target.die(ethRecipient);
         emit Killed(address(target), msg.sender);
     }
 }

contracts/zero-ex/contracts/src/features/BootstrapFeature.sol

@@ -22,12 +22,12 @@ pragma experimental ABIEncoderV2;
 import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
 import "../migrations/LibBootstrap.sol";
 import "../storage/LibProxyStorage.sol";
-import "./IBootstrap.sol";
+import "./IBootstrapFeature.sol";
 
 
 /// @dev Detachable `bootstrap()` feature.
-contract Bootstrap is
+contract BootstrapFeature is
-    IBootstrap
+    IBootstrapFeature
 {
     // solhint-disable state-visibility,indent
     /// @dev The ZeroEx contract.
@@ -69,7 +69,7 @@ contract Bootstrap is
         // Deregister.
         LibProxyStorage.getStorage().impls[this.bootstrap.selector] = address(0);
         // Self-destruct.
-        Bootstrap(_implementation).die();
+        BootstrapFeature(_implementation).die();
         // Call the bootstrapper.
         LibBootstrap.delegatecallBootstrapFunction(target, callData);
     }
@@ -77,6 +77,7 @@ contract Bootstrap is
     /// @dev Self-destructs this contract.
     ///      Can only be called by the deployer.
     function die() external {
+        assert(address(this) == _implementation);
         if (msg.sender != _deployer) {
             LibProxyRichErrors.InvalidDieCallerError(msg.sender, _deployer).rrevert();
         }

contracts/zero-ex/contracts/src/features/IBootstrapFeature.sol

@@ -21,7 +21,7 @@ pragma experimental ABIEncoderV2;
 
 
 /// @dev Detachable `bootstrap()` feature.
-interface IBootstrap {
+interface IBootstrapFeature {
 
     /// @dev Bootstrap the initial feature set of this contract by delegatecalling
     ///      into `target`. Before exiting the `bootstrap()` function will

contracts/zero-ex/contracts/src/features/IMetaTransactionsFeature.sol

@@ -23,7 +23,7 @@ import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
 
 
 /// @dev Meta-transactions feature.
-interface IMetaTransactions {
+interface IMetaTransactionsFeature {
 
     /// @dev Describes an exchange proxy meta transaction.
     struct MetaTransactionData {

contracts/zero-ex/contracts/src/features/IOwnableFeature.sol

@@ -24,7 +24,7 @@ import "@0x/contracts-utils/contracts/src/v06/interfaces/IOwnableV06.sol";
 
 // solhint-disable no-empty-blocks
 /// @dev Owner management and migration features.
-interface IOwnable is
+interface IOwnableFeature is
     IOwnableV06
 {
     /// @dev Emitted when `migrate()` is called.

contracts/zero-ex/contracts/src/features/ISignatureValidatorFeature.sol

@@ -21,7 +21,7 @@ pragma experimental ABIEncoderV2;
 
 
 /// @dev Feature for validating signatures.
-interface ISignatureValidator {
+interface ISignatureValidatorFeature {
 
    /// @dev Allowed signature types.
     enum SignatureType {

contracts/zero-ex/contracts/src/features/ISimpleFunctionRegistryFeature.sol

@@ -21,7 +21,7 @@ pragma experimental ABIEncoderV2;
 
 
 /// @dev Basic registry management features.
-interface ISimpleFunctionRegistry {
+interface ISimpleFunctionRegistryFeature {
 
     /// @dev A function implementation was updated via `extend()` or `rollback()`.
     /// @param selector The function selector.

contracts/zero-ex/contracts/src/features/ITokenSpenderFeature.sol

@@ -23,7 +23,7 @@ import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
 
 
 /// @dev Feature that allows spending token allowances.
-interface ITokenSpender {
+interface ITokenSpenderFeature {
 
     /// @dev Transfers ERC20 tokens from `owner` to `to`.
     ///      Only callable from within.

contracts/zero-ex/contracts/src/features/ITransformERC20Feature.sol

@@ -25,7 +25,7 @@ import "../external/IFlashWallet.sol";
 
 
 /// @dev Feature to composably transform between ERC20 tokens.
-interface ITransformERC20 {
+interface ITransformERC20Feature {
 
     /// @dev Defines a transformation to run in `transformERC20()`.
     struct Transformation {

contracts/zero-ex/contracts/src/features/MetaTransactionsFeature.sol

@@ -21,24 +21,27 @@ pragma experimental ABIEncoderV2;
 
 import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
 import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
+import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
 import "../errors/LibMetaTransactionsRichErrors.sol";
 import "../fixins/FixinCommon.sol";
+import "../fixins/FixinReentrancyGuard.sol";
 import "../fixins/FixinEIP712.sol";
 import "../migrations/LibMigrate.sol";
 import "../storage/LibMetaTransactionsStorage.sol";
 import "./libs/LibSignedCallData.sol";
-import "./IMetaTransactions.sol";
+import "./IMetaTransactionsFeature.sol";
-import "./ITransformERC20.sol";
+import "./ITransformERC20Feature.sol";
-import "./ISignatureValidator.sol";
+import "./ISignatureValidatorFeature.sol";
-import "./ITokenSpender.sol";
+import "./ITokenSpenderFeature.sol";
 import "./IFeature.sol";
 
 
 /// @dev MetaTransactions feature.
-contract MetaTransactions is
+contract MetaTransactionsFeature is
     IFeature,
-    IMetaTransactions,
+    IMetaTransactionsFeature,
     FixinCommon,
+    FixinReentrancyGuard,
     FixinEIP712
 {
     using LibBytesV06 for bytes;
@@ -69,7 +72,7 @@ contract MetaTransactions is
         IERC20TokenV06 outputToken;
         uint256 inputTokenAmount;
         uint256 minOutputTokenAmount;
-        ITransformERC20.Transformation[] transformations;
+        ITransformERC20Feature.Transformation[] transformations;
     }
 
     /// @dev Name of this feature.
@@ -92,6 +95,16 @@ contract MetaTransactions is
         ")"
     );
 
+    /// @dev Refunds up to `msg.value` leftover ETH at the end of the call.
+    modifier refundsAttachedEth() {
+        _;
+        uint256 remainingBalance =
+            LibSafeMathV06.min256(msg.value, address(this).balance);
+        if (remainingBalance > 0) {
+            msg.sender.transfer(remainingBalance);
+        }
+    }
+
     constructor(address zeroExAddress)
         public
         FixinCommon()
@@ -127,9 +140,11 @@ contract MetaTransactions is
         public
         payable
         override
+        nonReentrant(REENTRANCY_MTX)
+        refundsAttachedEth
         returns (bytes memory returnResult)
     {
-        return _executeMetaTransactionPrivate(
+        returnResult = _executeMetaTransactionPrivate(
             msg.sender,
             mtx,
             signature
@@ -147,6 +162,8 @@ contract MetaTransactions is
         public
         payable
         override
+        nonReentrant(REENTRANCY_MTX)
+        refundsAttachedEth
         returns (bytes[] memory returnResults)
     {
         if (mtxs.length != signatures.length) {
@@ -254,29 +271,31 @@ contract MetaTransactions is
 
         _validateMetaTransaction(state);
 
-        // Mark the transaction executed.
+        // Mark the transaction executed by storing the block at which it was executed.
-        assert(block.number > 0);
+        // Currently the block number just indicates that the mtx was executed and
+        // serves no other purpose from within this contract.
         LibMetaTransactionsStorage.getStorage()
             .mtxHashToExecutedBlockNumber[state.hash] = block.number;
 
-        // Execute the call based on the selector.
-        state.selector = mtx.callData.readBytes4(0);
-        if (state.selector == ITransformERC20.transformERC20.selector) {
-            returnResult = _executeTransformERC20Call(state);
-        } else {
-            LibMetaTransactionsRichErrors
-                .MetaTransactionUnsupportedFunctionError(state.hash, state.selector)
-                .rrevert();
-        }
         // Pay the fee to the sender.
         if (mtx.feeAmount > 0) {
-            ITokenSpender(address(this))._spendERC20Tokens(
+            ITokenSpenderFeature(address(this))._spendERC20Tokens(
                 mtx.feeToken,
                 mtx.signer, // From the signer.
                 sender, // To the sender.
                 mtx.feeAmount
             );
         }
+
+        // Execute the call based on the selector.
+        state.selector = mtx.callData.readBytes4(0);
+        if (state.selector == ITransformERC20Feature.transformERC20.selector) {
+            returnResult = _executeTransformERC20Call(state);
+        } else {
+            LibMetaTransactionsRichErrors
+                .MetaTransactionUnsupportedFunctionError(state.hash, state.selector)
+                .rrevert();
+        }
         emit MetaTransactionExecuted(
             state.hash,
             state.selector,
@@ -330,7 +349,7 @@ contract MetaTransactions is
         }
         // Must be signed by signer.
         try
-            ISignatureValidator(address(this))
+            ISignatureValidatorFeature(address(this))
                 .validateHashSignature(state.hash, state.mtx.signer, state.signature)
         {}
         catch (bytes memory err) {
@@ -353,9 +372,9 @@ contract MetaTransactions is
         }
     }
 
-    /// @dev Execute a `ITransformERC20.transformERC20()` meta-transaction call
+    /// @dev Execute a `ITransformERC20Feature.transformERC20()` meta-transaction call
     ///      by decoding the call args and translating the call to the internal
-    ///      `ITransformERC20._transformERC20()` variant, where we can override
+    ///      `ITransformERC20Feature._transformERC20()` variant, where we can override
     ///      the taker address.
     function _executeTransformERC20Call(ExecuteState memory state)
         private
@@ -367,7 +386,7 @@ contract MetaTransactions is
         // since decoding a single struct arg consumes far less stack space than
         // decoding multiple struct args.
 
-        // Where the encoding for multiple args (with the seleector ommitted)
+        // Where the encoding for multiple args (with the selector ommitted)
         // would typically look like:
         // | argument                 |  offset |
         // |--------------------------|---------|
@@ -394,7 +413,7 @@ contract MetaTransactions is
             bytes memory encodedStructArgs = new bytes(state.mtx.callData.length - 4 + 32);
             // Copy the args data from the original, after the new struct offset prefix.
             bytes memory fromCallData = state.mtx.callData;
-            assert(fromCallData.length >= 4);
+            assert(fromCallData.length >= 160);
             uint256 fromMem;
             uint256 toMem;
             assembly {
@@ -407,19 +426,19 @@ contract MetaTransactions is
                 toMem := add(encodedStructArgs, 64)
             }
             LibBytesV06.memCopy(toMem, fromMem, fromCallData.length - 4);
-            // Decode call args for `ITransformERC20.transformERC20()` as a struct.
+            // Decode call args for `ITransformERC20Feature.transformERC20()` as a struct.
             args = abi.decode(encodedStructArgs, (ExternalTransformERC20Args));
         }
         // Parse the signature and hash out of the calldata so `_transformERC20()`
         // can authenticate it.
         (bytes32 callDataHash, bytes memory callDataSignature) =
             LibSignedCallData.parseCallData(state.mtx.callData);
-        // Call `ITransformERC20._transformERC20()` (internal variant).
+        // Call `ITransformERC20Feature._transformERC20()` (internal variant).
         return _callSelf(
             state.hash,
             abi.encodeWithSelector(
-                ITransformERC20._transformERC20.selector,
+                ITransformERC20Feature._transformERC20.selector,
-                ITransformERC20.TransformERC20Args({
+                ITransformERC20Feature.TransformERC20Args({
                     taker: state.mtx.signer, // taker is mtx signer
                     inputToken: args.inputToken,
                     outputToken: args.outputToken,

contracts/zero-ex/contracts/src/features/OwnableFeature.sol

@@ -26,14 +26,14 @@ import "../storage/LibOwnableStorage.sol";
 import "../migrations/LibBootstrap.sol";
 import "../migrations/LibMigrate.sol";
 import "./IFeature.sol";
-import "./IOwnable.sol";
+import "./IOwnableFeature.sol";
-import "./SimpleFunctionRegistry.sol";
+import "./SimpleFunctionRegistryFeature.sol";
 
 
 /// @dev Owner management features.
-contract Ownable is
+contract OwnableFeature is
     IFeature,
-    IOwnable,
+    IOwnableFeature,
     FixinCommon
 {
 
@@ -44,10 +44,6 @@ contract Ownable is
 
     using LibRichErrorsV06 for bytes;
 
-    constructor() public FixinCommon() {
-        // solhint-disable-next-line no-empty-blocks
-    }
-
     /// @dev Initializes this feature. The intial owner will be set to this (ZeroEx)
     ///      to allow the bootstrappers to call `extend()`. Ownership should be
     ///      transferred to the real owner by the bootstrapper after
@@ -58,9 +54,9 @@ contract Ownable is
         LibOwnableStorage.getStorage().owner = address(this);
 
         // Register feature functions.
-        SimpleFunctionRegistry(address(this))._extendSelf(this.transferOwnership.selector, _implementation);
+        SimpleFunctionRegistryFeature(address(this))._extendSelf(this.transferOwnership.selector, _implementation);
-        SimpleFunctionRegistry(address(this))._extendSelf(this.owner.selector, _implementation);
+        SimpleFunctionRegistryFeature(address(this))._extendSelf(this.owner.selector, _implementation);
-        SimpleFunctionRegistry(address(this))._extendSelf(this.migrate.selector, _implementation);
+        SimpleFunctionRegistryFeature(address(this))._extendSelf(this.migrate.selector, _implementation);
         return LibBootstrap.BOOTSTRAP_SUCCESS;
     }
 

contracts/zero-ex/contracts/src/features/SignatureValidatorFeature.sol

@@ -24,28 +24,31 @@ import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
 import "../errors/LibSignatureRichErrors.sol";
 import "../fixins/FixinCommon.sol";
 import "../migrations/LibMigrate.sol";
-import "./ISignatureValidator.sol";
+import "./ISignatureValidatorFeature.sol";
 import "./IFeature.sol";
 
 
 /// @dev Feature for validating signatures.
-contract SignatureValidator is
+contract SignatureValidatorFeature is
     IFeature,
-    ISignatureValidator,
+    ISignatureValidatorFeature,
     FixinCommon
 {
     using LibBytesV06 for bytes;
     using LibRichErrorsV06 for bytes;
 
+    /// @dev Exclusive upper limit on ECDSA signatures 'R' values.
+    ///      The valid range is given by fig (282) of the yellow paper.
+    uint256 private constant ECDSA_SIGNATURE_R_LIMIT =
+        uint256(0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141);
+    /// @dev Exclusive upper limit on ECDSA signatures 'S' values.
+    ///      The valid range is given by fig (283) of the yellow paper.
+    uint256 private constant ECDSA_SIGNATURE_S_LIMIT = ECDSA_SIGNATURE_R_LIMIT / 2 + 1;
     /// @dev Name of this feature.
     string public constant override FEATURE_NAME = "SignatureValidator";
     /// @dev Version of this feature.
     uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 0, 0);
 
-    constructor() public FixinCommon() {
-        // solhint-disable-next-line no-empty-blocks
-    }
-
     /// @dev Initialize and register this feature.
     ///      Should be delegatecalled by `Migrate.migrate()`.
     /// @return success `LibMigrate.SUCCESS` on success.
@@ -160,12 +163,14 @@ contract SignatureValidator is
             uint8 v = uint8(signature[0]);
             bytes32 r = signature.readBytes32(1);
             bytes32 s = signature.readBytes32(33);
+            if (uint256(r) < ECDSA_SIGNATURE_R_LIMIT && uint256(s) < ECDSA_SIGNATURE_S_LIMIT) {
                 recovered = ecrecover(
                     hash,
                     v,
                     r,
                     s
                 );
+            }
         } else if (signatureType == SignatureType.EthSign) {
             // Signed using `eth_sign`
             if (signature.length != 66) {
@@ -179,6 +184,7 @@ contract SignatureValidator is
             uint8 v = uint8(signature[0]);
             bytes32 r = signature.readBytes32(1);
             bytes32 s = signature.readBytes32(33);
+            if (uint256(r) < ECDSA_SIGNATURE_R_LIMIT && uint256(s) < ECDSA_SIGNATURE_S_LIMIT) {
                 recovered = ecrecover(
                     keccak256(abi.encodePacked(
                         "\x19Ethereum Signed Message:\n32",
@@ -188,6 +194,7 @@ contract SignatureValidator is
                     r,
                     s
                 );
+            }
         } else {
             // This should never happen.
             revert('SignatureValidator/ILLEGAL_CODE_PATH');

contracts/zero-ex/contracts/src/features/SimpleFunctionRegistryFeature.sol

@@ -26,13 +26,13 @@ import "../storage/LibSimpleFunctionRegistryStorage.sol";
 import "../errors/LibSimpleFunctionRegistryRichErrors.sol";
 import "../migrations/LibBootstrap.sol";
 import "./IFeature.sol";
-import "./ISimpleFunctionRegistry.sol";
+import "./ISimpleFunctionRegistryFeature.sol";
 
 
 /// @dev Basic registry management features.
-contract SimpleFunctionRegistry is
+contract SimpleFunctionRegistryFeature is
     IFeature,
-    ISimpleFunctionRegistry,
+    ISimpleFunctionRegistryFeature,
     FixinCommon
 {
     /// @dev Name of this feature.
@@ -42,10 +42,6 @@ contract SimpleFunctionRegistry is
 
     using LibRichErrorsV06 for bytes;
 
-    constructor() public FixinCommon() {
-        // solhint-disable-next-line no-empty-blocks
-    }
-
     /// @dev Initializes this feature, registering its own functions.
     /// @return success Magic bytes if successful.
     function bootstrap()

contracts/zero-ex/contracts/src/features/TokenSpenderFeature.sol

@@ -28,15 +28,14 @@ import "../fixins/FixinCommon.sol";
 import "../migrations/LibMigrate.sol";
 import "../external/IAllowanceTarget.sol";
 import "../storage/LibTokenSpenderStorage.sol";
-import "./ITokenSpender.sol";
+import "./ITokenSpenderFeature.sol";
 import "./IFeature.sol";
-import "./ISimpleFunctionRegistry.sol";
 
 
 /// @dev Feature that allows spending token allowances.
-contract TokenSpender is
+contract TokenSpenderFeature is
     IFeature,
-    ITokenSpender,
+    ITokenSpenderFeature,
     FixinCommon
 {
     // solhint-disable
@@ -48,10 +47,6 @@ contract TokenSpender is
 
     using LibRichErrorsV06 for bytes;
 
-    constructor() public FixinCommon() {
-        // solhint-disable-next-line no-empty-blocks
-    }
-
     /// @dev Initialize and register this feature. Should be delegatecalled
     ///      into during a `Migrate.migrate()`.
     /// @param allowanceTarget An `allowanceTarget` instance, configured to have

contracts/zero-ex/contracts/src/features/TransformERC20Feature.sol

@@ -32,17 +32,16 @@ import "../storage/LibTransformERC20Storage.sol";
 import "../transformers/IERC20Transformer.sol";
 import "../transformers/LibERC20Transformer.sol";
 import "./libs/LibSignedCallData.sol";
-import "./ITransformERC20.sol";
+import "./ITransformERC20Feature.sol";
-import "./ITokenSpender.sol";
+import "./ITokenSpenderFeature.sol";
 import "./IFeature.sol";
-import "./ISignatureValidator.sol";
+import "./ISignatureValidatorFeature.sol";
-import "./ISimpleFunctionRegistry.sol";
 
 
 /// @dev Feature to composably transform between ERC20 tokens.
-contract TransformERC20 is
+contract TransformERC20Feature is
     IFeature,
-    ITransformERC20,
+    ITransformERC20Feature,
     FixinCommon
 {
     using LibSafeMathV06 for uint256;
@@ -61,10 +60,6 @@ contract TransformERC20 is
     /// @dev Version of this feature.
     uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 2, 0);
 
-    constructor() public FixinCommon() {
-        // solhint-disable-next-line no-empty-blocks
-    }
-
     /// @dev Initialize and register this feature.
     ///      Should be delegatecalled by `Migrate.migrate()`.
     /// @param transformerDeployer The trusted deployer for transformers.
@@ -81,7 +76,10 @@ contract TransformERC20 is
         _registerFeatureFunction(this.getQuoteSigner.selector);
         _registerFeatureFunction(this.transformERC20.selector);
         _registerFeatureFunction(this._transformERC20.selector);
+        if (this.getTransformWallet() == IFlashWallet(address(0))) {
+            // Create the transform wallet if it doesn't exist.
             this.createTransformWallet();
+        }
         LibTransformERC20Storage.getStorage().transformerDeployer = transformerDeployer;
         return LibMigrate.MIGRATE_SUCCESS;
     }
@@ -213,7 +211,7 @@ contract TransformERC20 is
         // If the input token amount is -1, transform the taker's entire
         // spendable balance.
         if (args.inputTokenAmount == uint256(-1)) {
-            args.inputTokenAmount = ITokenSpender(address(this))
+            args.inputTokenAmount = ITokenSpenderFeature(address(this))
                 .getSpendableERC20BalanceOf(args.inputToken, args.taker);
         }
 
@@ -257,16 +255,15 @@ contract TransformERC20 is
         // Compute how much output token has been transferred to the taker.
         state.takerOutputTokenBalanceAfter =
             LibERC20Transformer.getTokenBalanceOf(args.outputToken, args.taker);
-        if (state.takerOutputTokenBalanceAfter > state.takerOutputTokenBalanceBefore) {
+        if (state.takerOutputTokenBalanceAfter < state.takerOutputTokenBalanceBefore) {
-            outputTokenAmount = state.takerOutputTokenBalanceAfter.safeSub(
-                state.takerOutputTokenBalanceBefore
-            );
-        } else if (state.takerOutputTokenBalanceAfter < state.takerOutputTokenBalanceBefore) {
             LibTransformERC20RichErrors.NegativeTransformERC20OutputError(
                 address(args.outputToken),
                 state.takerOutputTokenBalanceBefore - state.takerOutputTokenBalanceAfter
             ).rrevert();
         }
+        outputTokenAmount = state.takerOutputTokenBalanceAfter.safeSub(
+            state.takerOutputTokenBalanceBefore
+        );
         // Ensure enough output token has been sent to the taker.
         if (outputTokenAmount < args.minOutputTokenAmount) {
             LibTransformERC20RichErrors.IncompleteTransformERC20Error(
@@ -318,7 +315,7 @@ contract TransformERC20 is
         // Transfer input tokens.
         if (!LibERC20Transformer.isTokenETH(inputToken)) {
             // Token is not ETH, so pull ERC20 tokens.
-            ITokenSpender(address(this))._spendERC20Tokens(
+            ITokenSpenderFeature(address(this))._spendERC20Tokens(
                 inputToken,
                 from,
                 to,
@@ -360,9 +357,12 @@ contract TransformERC20 is
             // Call data.
             abi.encodeWithSelector(
                 IERC20Transformer.transform.selector,
-                callDataHash,
+                IERC20Transformer.TransformContext({
-                taker,
+                    callDataHash: callDataHash,
-                transformation.data
+                    sender: msg.sender,
+                    taker: taker,
+                    data: transformation.data
+                })
             )
         );
         // Ensure the transformer returned the magic bytes.
@@ -389,13 +389,19 @@ contract TransformERC20 is
         view
         returns (bytes32 validCallDataHash)
     {
+        address quoteSigner = getQuoteSigner();
+        if (quoteSigner == address(0)) {
+            // If no quote signer is configured, then all calldata hashes are
+            // valid.
+            return callDataHash;
+        }
         if (signature.length == 0) {
             return bytes32(0);
         }
 
-        if (ISignatureValidator(address(this)).isValidHashSignature(
+        if (ISignatureValidatorFeature(address(this)).isValidHashSignature(
             callDataHash,
-            getQuoteSigner(),
+            quoteSigner,
             signature
         )) {
             return callDataHash;

contracts/zero-ex/contracts/src/fixins/FixinCommon.sol

@@ -22,8 +22,8 @@ pragma experimental ABIEncoderV2;
 import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
 import "../errors/LibCommonRichErrors.sol";
 import "../errors/LibOwnableRichErrors.sol";
-import "../features/IOwnable.sol";
+import "../features/IOwnableFeature.sol";
-import "../features/ISimpleFunctionRegistry.sol";
+import "../features/ISimpleFunctionRegistryFeature.sol";
 
 
 /// @dev Common feature utilities.
@@ -45,7 +45,7 @@ abstract contract FixinCommon {
     /// @dev The caller of this function must be the owner.
     modifier onlyOwner() virtual {
         {
-            address owner = IOwnable(address(this)).owner();
+            address owner = IOwnableFeature(address(this)).owner();
             if (msg.sender != owner) {
                 LibOwnableRichErrors.OnlyOwnerError(
                     msg.sender,
@@ -68,7 +68,7 @@ abstract contract FixinCommon {
     function _registerFeatureFunction(bytes4 selector)
         internal
     {
-        ISimpleFunctionRegistry(address(this)).extend(selector, _implementation);
+        ISimpleFunctionRegistryFeature(address(this)).extend(selector, _implementation);
     }
 
     /// @dev Encode a feature version as a `uint256`.

contracts/zero-ex/contracts/src/fixins/FixinEIP712.sol

@@ -22,7 +22,6 @@ pragma experimental ABIEncoderV2;
 import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
 import "../errors/LibCommonRichErrors.sol";
 import "../errors/LibOwnableRichErrors.sol";
-import "../features/IOwnable.sol";
 
 
 /// @dev EIP712 helpers for features.

contracts/zero-ex/contracts/src/fixins/FixinReentrancyGuard.sol

@@ -0,0 +1,60 @@
+/*
+
+  Copyright 2020 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 ^0.6.5;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
+import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
+import "../errors/LibCommonRichErrors.sol";
+import "../storage/LibReentrancyGuardStorage.sol";
+
+
+/// @dev Common feature utilities.
+abstract contract FixinReentrancyGuard {
+
+    using LibRichErrorsV06 for bytes;
+    using LibBytesV06 for bytes;
+
+    // Combinable reentrancy flags.
+    /// @dev Reentrancy guard flag for meta-transaction functions.
+    uint256 constant internal REENTRANCY_MTX = 0x1;
+
+    /// @dev Cannot reenter a function with the same reentrancy guard flags.
+    modifier nonReentrant(uint256 reentrancyFlags) virtual {
+        LibReentrancyGuardStorage.Storage storage stor =
+            LibReentrancyGuardStorage.getStorage();
+        {
+            uint256 currentFlags = stor.reentrancyFlags;
+            // Revert if any bits in `reentrancyFlags` has already been set.
+            if ((currentFlags & reentrancyFlags) != 0) {
+                LibCommonRichErrors.IllegalReentrancyError(
+                    msg.data.readBytes4(0),
+                    reentrancyFlags
+                ).rrevert();
+            }
+            // Update reentrancy flags.
+            stor.reentrancyFlags = currentFlags | reentrancyFlags;
+        }
+
+        _;
+
+        // Clear reentrancy flags.
+        stor.reentrancyFlags = stor.reentrancyFlags & (~reentrancyFlags);
+    }
+}

contracts/zero-ex/contracts/src/migrations/FullMigration.sol

@@ -20,11 +20,11 @@ pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
 import "../ZeroEx.sol";
-import "../features/IOwnable.sol";
+import "../features/IOwnableFeature.sol";
-import "../features/TokenSpender.sol";
+import "../features/TokenSpenderFeature.sol";
-import "../features/TransformERC20.sol";
+import "../features/TransformERC20Feature.sol";
-import "../features/SignatureValidator.sol";
+import "../features/SignatureValidatorFeature.sol";
-import "../features/MetaTransactions.sol";
+import "../features/MetaTransactionsFeature.sol";
 import "../external/AllowanceTarget.sol";
 import "./InitialMigration.sol";
 
@@ -36,12 +36,12 @@ contract FullMigration {
 
     /// @dev Features to add the the proxy contract.
     struct Features {
-        SimpleFunctionRegistry registry;
+        SimpleFunctionRegistryFeature registry;
-        Ownable ownable;
+        OwnableFeature ownable;
-        TokenSpender tokenSpender;
+        TokenSpenderFeature tokenSpender;
-        TransformERC20 transformERC20;
+        TransformERC20Feature transformERC20;
-        SignatureValidator signatureValidator;
+        SignatureValidatorFeature signatureValidator;
-        MetaTransactions metaTransactions;
+        MetaTransactionsFeature metaTransactions;
     }
 
     /// @dev Parameters needed to initialize features.
@@ -109,7 +109,7 @@ contract FullMigration {
         _addFeatures(zeroEx, owner, features, migrateOpts);
 
         // Transfer ownership to the real owner.
-        IOwnable(address(zeroEx)).transferOwnership(owner);
+        IOwnableFeature(address(zeroEx)).transferOwnership(owner);
 
         // Self-destruct.
         this.die(owner);
@@ -142,8 +142,8 @@ contract FullMigration {
     )
         private
     {
-        IOwnable ownable = IOwnable(address(zeroEx));
+        IOwnableFeature ownable = IOwnableFeature(address(zeroEx));
-        // TokenSpender
+        // TokenSpenderFeature
         {
             // Create the allowance target.
             AllowanceTarget allowanceTarget = new AllowanceTarget();
@@ -155,42 +155,42 @@ contract FullMigration {
             ownable.migrate(
                 address(features.tokenSpender),
                 abi.encodeWithSelector(
-                    TokenSpender.migrate.selector,
+                    TokenSpenderFeature.migrate.selector,
                     allowanceTarget
                 ),
                 address(this)
             );
         }
-        // TransformERC20
+        // TransformERC20Feature
         {
             // Register the feature.
             ownable.migrate(
                 address(features.transformERC20),
                 abi.encodeWithSelector(
-                    TransformERC20.migrate.selector,
+                    TransformERC20Feature.migrate.selector,
                     migrateOpts.transformerDeployer
                 ),
                 address(this)
             );
         }
-        // SignatureValidator
+        // SignatureValidatorFeature
         {
             // Register the feature.
             ownable.migrate(
                 address(features.signatureValidator),
                 abi.encodeWithSelector(
-                    SignatureValidator.migrate.selector
+                    SignatureValidatorFeature.migrate.selector
                 ),
                 address(this)
             );
         }
-        // MetaTransactions
+        // MetaTransactionsFeature
         {
             // Register the feature.
             ownable.migrate(
                 address(features.metaTransactions),
                 abi.encodeWithSelector(
-                    MetaTransactions.migrate.selector
+                    MetaTransactionsFeature.migrate.selector
                 ),
                 address(this)
             );

contracts/zero-ex/contracts/src/migrations/InitialMigration.sol

@@ -20,9 +20,9 @@ pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
 import "../ZeroEx.sol";
-import "../features/IBootstrap.sol";
+import "../features/IBootstrapFeature.sol";
-import "../features/SimpleFunctionRegistry.sol";
+import "../features/SimpleFunctionRegistryFeature.sol";
-import "../features/Ownable.sol";
+import "../features/OwnableFeature.sol";
 import "./LibBootstrap.sol";
 
 
@@ -31,8 +31,8 @@ contract InitialMigration {
 
     /// @dev Features to bootstrap into the the proxy contract.
     struct BootstrapFeatures {
-        SimpleFunctionRegistry registry;
+        SimpleFunctionRegistryFeature registry;
-        Ownable ownable;
+        OwnableFeature ownable;
     }
 
     /// @dev The allowed caller of `initializeZeroEx()`. In production, this would be
@@ -70,7 +70,7 @@ contract InitialMigration {
         require(msg.sender == initializeCaller, "InitialMigration/INVALID_SENDER");
 
         // Bootstrap the initial feature set.
-        IBootstrap(address(zeroEx)).bootstrap(
+        IBootstrapFeature(address(zeroEx)).bootstrap(
             address(this),
             abi.encodeWithSelector(this.bootstrap.selector, owner, features)
         );
@@ -99,26 +99,26 @@ contract InitialMigration {
         LibBootstrap.delegatecallBootstrapFunction(
             address(features.registry),
             abi.encodeWithSelector(
-                SimpleFunctionRegistry.bootstrap.selector
+                SimpleFunctionRegistryFeature.bootstrap.selector
             )
         );
 
-        // Initialize Ownable.
+        // Initialize OwnableFeature.
         LibBootstrap.delegatecallBootstrapFunction(
             address(features.ownable),
             abi.encodeWithSelector(
-                Ownable.bootstrap.selector
+                OwnableFeature.bootstrap.selector
             )
         );
 
-        // De-register `SimpleFunctionRegistry._extendSelf`.
+        // De-register `SimpleFunctionRegistryFeature._extendSelf`.
-        SimpleFunctionRegistry(address(this)).rollback(
+        SimpleFunctionRegistryFeature(address(this)).rollback(
-            SimpleFunctionRegistry._extendSelf.selector,
+            SimpleFunctionRegistryFeature._extendSelf.selector,
             address(0)
         );
 
         // Transfer ownership to the real owner.
-        Ownable(address(this)).transferOwnership(owner);
+        OwnableFeature(address(this)).transferOwnership(owner);
 
         success = LibBootstrap.BOOTSTRAP_SUCCESS;
     }

contracts/zero-ex/contracts/src/storage/LibReentrancyGuardStorage.sol

@@ -0,0 +1,46 @@
+/*
+
+  Copyright 2020 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 ^0.6.5;
+pragma experimental ABIEncoderV2;
+
+import "./LibStorage.sol";
+import "../external/IFlashWallet.sol";
+
+
+/// @dev Storage helpers for the `FixinReentrancyGuard` mixin.
+library LibReentrancyGuardStorage {
+
+    /// @dev Storage bucket for this feature.
+    struct Storage {
+        // Reentrancy flags set whenever a non-reentrant function is entered
+        // and cleared when it is exited.
+        uint256 reentrancyFlags;
+    }
+
+    /// @dev Get the storage bucket for this contract.
+    function getStorage() internal pure returns (Storage storage stor) {
+        uint256 storageSlot = LibStorage.getStorageSlot(
+            LibStorage.StorageId.ReentrancyGuard
+        );
+        // Dip into assembly to change the slot pointed to by the local
+        // variable `stor`.
+        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
+        assembly { stor_slot := storageSlot }
+    }
+}

contracts/zero-ex/contracts/src/storage/LibStorage.sol

@@ -35,7 +35,8 @@ library LibStorage {
         Ownable,
         TokenSpender,
         TransformERC20,
-        MetaTransactions
+        MetaTransactions,
+        ReentrancyGuard
     }
 
     /// @dev Get the storage slot given a storage ID. We assign unique, well-spaced

contracts/zero-ex/contracts/src/transformers/AffiliateFeeTransformer.sol

@@ -32,7 +32,6 @@ import "./LibERC20Transformer.sol";
 contract AffiliateFeeTransformer is
     Transformer
 {
-    // solhint-disable no-empty-blocks
     using LibRichErrorsV06 for bytes;
     using LibSafeMathV06 for uint256;
     using LibERC20Transformer for IERC20TokenV06;
@@ -51,25 +50,15 @@ contract AffiliateFeeTransformer is
 
     uint256 private constant MAX_UINT256 = uint256(-1);
 
-    /// @dev Create this contract.
-    constructor()
-        public
-        Transformer()
-    {}
-
     /// @dev Transfers tokens to recipients.
-    /// @param data ABI-encoded `TokenFee[]`, indicating which tokens to transfer.
+    /// @param context Context information.
     /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32, // callDataHash,
-        address payable, // taker,
-        bytes calldata data
-    )
         external
         override
         returns (bytes4 success)
     {
-        TokenFee[] memory fees = abi.decode(data, (TokenFee[]));
+        TokenFee[] memory fees = abi.decode(context.data, (TokenFee[]));
 
         // Transfer tokens to recipients.
         for (uint256 i = 0; i < fees.length; ++i) {

contracts/zero-ex/contracts/src/transformers/FillQuoteTransformer.sol

@@ -27,7 +27,7 @@ import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
 import "@0x/contracts-utils/contracts/src/v06/LibMathV06.sol";
 import "../errors/LibTransformERC20RichErrors.sol";
 import "../vendor/v3/IExchange.sol";
-import "../bridges/IBridgeAdapter.sol";
+import "./bridges/IBridgeAdapter.sol";
 import "./Transformer.sol";
 import "./LibERC20Transformer.sol";
 
@@ -50,7 +50,7 @@ contract FillQuoteTransformer is
 
     /// @dev Transform data to ABI-encode and pass into `transform()`.
     struct TransformData {
-        // Whether we aer performing a market sell or buy.
+        // Whether we are performing a market sell or buy.
         Side side;
         // The token being sold.
         // This should be an actual token, not the ETH pseudo-token.
@@ -71,6 +71,15 @@ contract FillQuoteTransformer is
         // For sells, this may be `uint256(-1)` to sell the entire balance of
         // `sellToken`.
         uint256 fillAmount;
+        // Who to transfer unused protocol fees to.
+        // May be a valid address or one of:
+        // `address(0)`: Stay in flash wallet.
+        // `address(1)`: Send to the taker.
+        // `address(2)`: Send to the sender (caller of `transformERC20()`).
+        address payable refundReceiver;
+        // Required taker address for RFQT orders.
+        // Null means any taker can fill it.
+        address rfqtTakerAddress;
     }
 
     /// @dev Results of a call to `_fillOrder()`.
@@ -90,6 +99,7 @@ contract FillQuoteTransformer is
         uint256 soldAmount;
         uint256 protocolFee;
         uint256 takerTokenBalanceRemaining;
+        bool isRfqtAllowed;
     }
 
     /// @dev Emitted when a trade is skipped due to a lack of funds
@@ -108,6 +118,12 @@ contract FillQuoteTransformer is
     bytes4 private constant ERC20_BRIDGE_PROXY_ID = 0xdc1600f3;
     /// @dev Maximum uint256 value.
     uint256 private constant MAX_UINT256 = uint256(-1);
+    /// @dev If `refundReceiver` is set to this address, unpsent
+    ///      protocol fees will be sent to the taker.
+    address private constant REFUND_RECEIVER_TAKER = address(1);
+    /// @dev If `refundReceiver` is set to this address, unpsent
+    ///      protocol fees will be sent to the sender.
+    address private constant REFUND_RECEIVER_SENDER = address(2);
 
     /// @dev The Exchange contract.
     IExchange public immutable exchange;
@@ -130,31 +146,27 @@ contract FillQuoteTransformer is
     /// @dev Sell this contract's entire balance of of `sellToken` in exchange
     ///      for `buyToken` by filling `orders`. Protocol fees should be attached
     ///      to this call. `buyToken` and excess ETH will be transferred back to the caller.
-    /// @param data_ ABI-encoded `TransformData`.
+    /// @param context Context information.
     /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32, // callDataHash,
-        address payable, // taker,
-        bytes calldata data_
-    )
         external
         override
         returns (bytes4 success)
     {
-        TransformData memory data = abi.decode(data_, (TransformData));
+        TransformData memory data = abi.decode(context.data, (TransformData));
         FillState memory state;
 
         // Validate data fields.
         if (data.sellToken.isTokenETH() || data.buyToken.isTokenETH()) {
             LibTransformERC20RichErrors.InvalidTransformDataError(
                 LibTransformERC20RichErrors.InvalidTransformDataErrorCode.INVALID_TOKENS,
-                data_
+                context.data
             ).rrevert();
         }
         if (data.orders.length != data.signatures.length) {
             LibTransformERC20RichErrors.InvalidTransformDataError(
                 LibTransformERC20RichErrors.InvalidTransformDataErrorCode.INVALID_ARRAY_LENGTH,
-                data_
+                context.data
             ).rrevert();
         }
 
@@ -170,9 +182,14 @@ contract FillQuoteTransformer is
         // Approve the ERC20 proxy to spend `sellToken`.
         data.sellToken.approveIfBelow(erc20Proxy, data.fillAmount);
 
-        // Fill the orders.
         state.protocolFee = exchange.protocolFeeMultiplier().safeMul(tx.gasprice);
         state.ethRemaining = address(this).balance;
+        // RFQT orders can only be filled if we have a valid calldata hash
+        // (calldata was signed), and the actual taker matches the RFQT taker (if set).
+        state.isRfqtAllowed = context.callDataHash != bytes32(0)
+            && (data.rfqtTakerAddress == address(0) || context.taker == data.rfqtTakerAddress);
+
+        // Fill the orders.
         for (uint256 i = 0; i < data.orders.length; ++i) {
             // Check if we've hit our targets.
             if (data.side == Side.Sell) {
@@ -248,6 +265,17 @@ contract FillQuoteTransformer is
                     ).rrevert();
             }
         }
+
+        // Refund unspent protocol fees.
+        if (state.ethRemaining > 0 && data.refundReceiver != address(0)) {
+            if (data.refundReceiver == REFUND_RECEIVER_TAKER) {
+                context.taker.transfer(state.ethRemaining);
+            } else if (data.refundReceiver == REFUND_RECEIVER_SENDER) {
+                context.sender.transfer(state.ethRemaining);
+            } else {
+                data.refundReceiver.transfer(state.ethRemaining);
+            }
+        }
         return LibERC20Transformer.TRANSFORMER_SUCCESS;
     }
 
@@ -415,6 +443,11 @@ contract FillQuoteTransformer is
             }
             return results;
         } else {
+            // If the order taker address is set to this contract's address then
+            // this is an RFQT order, and we will only fill it if allowed to.
+            if (order.takerAddress == address(this) && !state.isRfqtAllowed) {
+                return results; // Empty results.
+            }
             // Emit an event if we do not have sufficient ETH to cover the protocol fee.
             if (state.ethRemaining < state.protocolFee) {
                 emit ProtocolFeeUnfunded(state.ethRemaining, state.protocolFee);

contracts/zero-ex/contracts/src/transformers/IERC20Transformer.sol

@@ -25,17 +25,25 @@ import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
 /// @dev A transformation callback used in `TransformERC20.transformERC20()`.
 interface IERC20Transformer {
 
+    /// @dev Context information to pass into `transform()` by `TransformERC20.transformERC20()`.
+    struct TransformContext {
+        // The hash of the `TransformERC20.transformERC20()` calldata.
+        // Will be null if the calldata is not signed.
+        bytes32 callDataHash;
+        // The caller of `TransformERC20.transformERC20()`.
+        address payable sender;
+        // taker The taker address, which may be distinct from `sender` in the case
+        // meta-transactions.
+        address payable taker;
+        // Arbitrary data to pass to the transformer.
+        bytes data;
+    }
+
     /// @dev Called from `TransformERC20.transformERC20()`. This will be
     ///      delegatecalled in the context of the FlashWallet instance being used.
-    /// @param callDataHash The hash of the `TransformERC20.transformERC20()` calldata.
+    /// @param context Context information.
-    /// @param taker The taker address (caller of `TransformERC20.transformERC20()`).
-    /// @param data Arbitrary data to pass to the transformer.
     /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32 callDataHash,
-        address payable taker,
-        bytes calldata data
-    )
         external
         returns (bytes4 success);
 }

contracts/zero-ex/contracts/src/transformers/LogMetadataTransformer.sol

@@ -0,0 +1,46 @@
+/*
+
+  Copyright 2020 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 ^0.6.5;
+pragma experimental ABIEncoderV2;
+
+import "./Transformer.sol";
+import "./LibERC20Transformer.sol";
+
+
+/// @dev A transformer that just emits an event with an arbitrary byte payload.
+contract LogMetadataTransformer is
+    Transformer
+{
+    event TransformerMetadata(bytes32 callDataHash, address sender, address taker, bytes data);
+
+    /// @dev Maximum uint256 value.
+    uint256 private constant MAX_UINT256 = uint256(-1);
+
+    /// @dev Emits an event.
+    /// @param context Context information.
+    /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
+    function transform(TransformContext calldata context)
+        external
+        override
+        returns (bytes4 success)
+    {
+        emit TransformerMetadata(context.callDataHash, context.sender, context.taker, context.data);
+        return LibERC20Transformer.TRANSFORMER_SUCCESS;
+    }
+}

contracts/zero-ex/contracts/src/transformers/PayTakerTransformer.sol

@@ -56,19 +56,14 @@ contract PayTakerTransformer is
     {}
 
     /// @dev Forwards tokens to the taker.
-    /// @param taker The taker address (caller of `TransformERC20.transformERC20()`).
+    /// @param context Context information.
-    /// @param data_ ABI-encoded `TransformData`, indicating which tokens to transfer.
     /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32, // callDataHash,
-        address payable taker,
-        bytes calldata data_
-    )
         external
         override
         returns (bytes4 success)
     {
-        TransformData memory data = abi.decode(data_, (TransformData));
+        TransformData memory data = abi.decode(context.data, (TransformData));
 
         // Transfer tokens directly to the taker.
         for (uint256 i = 0; i < data.tokens.length; ++i) {
@@ -79,7 +74,7 @@ contract PayTakerTransformer is
                 amount = data.tokens[i].getTokenBalanceOf(address(this));
             }
             if (amount != 0) {
-                data.tokens[i].transformerTransfer(taker, amount);
+                data.tokens[i].transformerTransfer(context.taker, amount);
             }
         }
         return LibERC20Transformer.TRANSFORMER_SUCCESS;

contracts/zero-ex/contracts/src/transformers/WethTransformer.sol

@@ -59,22 +59,18 @@ contract WethTransformer is
     }
 
     /// @dev Wraps and unwraps WETH.
-    /// @param data_ ABI-encoded `TransformData`, indicating which token to wrap/umwrap.
+    /// @param context Context information.
     /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32, // callDataHash,
-        address payable, // taker,
-        bytes calldata data_
-    )
         external
         override
         returns (bytes4 success)
     {
-        TransformData memory data = abi.decode(data_, (TransformData));
+        TransformData memory data = abi.decode(context.data, (TransformData));
         if (!data.token.isTokenETH() && data.token != weth) {
             LibTransformERC20RichErrors.InvalidTransformDataError(
                 LibTransformERC20RichErrors.InvalidTransformDataErrorCode.INVALID_TOKENS,
-                data_
+                context.data
             ).rrevert();
         }
 

contracts/zero-ex/contracts/src/transformers/bridges/BridgeAdapter.sol

@@ -23,6 +23,7 @@ import "./mixins/MixinAdapterAddresses.sol";
 import "./mixins/MixinBalancer.sol";
 import "./mixins/MixinCurve.sol";
 import "./mixins/MixinKyber.sol";
+import "./mixins/MixinMooniswap.sol";
 import "./mixins/MixinMStable.sol";
 import "./mixins/MixinOasis.sol";
 import "./mixins/MixinUniswap.sol";
@@ -34,6 +35,7 @@ contract BridgeAdapter is
     MixinBalancer,
     MixinCurve,
     MixinKyber,
+    MixinMooniswap,
     MixinMStable,
     MixinOasis,
     MixinUniswap,
@@ -44,6 +46,7 @@ contract BridgeAdapter is
     address private immutable BALANCER_BRIDGE_ADDRESS;
     address private immutable CURVE_BRIDGE_ADDRESS;
     address private immutable KYBER_BRIDGE_ADDRESS;
+    address private immutable MOONISWAP_BRIDGE_ADDRESS;
     address private immutable MSTABLE_BRIDGE_ADDRESS;
     address private immutable OASIS_BRIDGE_ADDRESS;
     address private immutable UNISWAP_BRIDGE_ADDRESS;
@@ -57,8 +60,8 @@ contract BridgeAdapter is
     /// @param from The bridge address, indicating the underlying source of the fill.
     /// @param to The `to` address, currrently `address(this)`
     event ERC20BridgeTransfer(
-        address inputToken,
+        IERC20TokenV06 inputToken,
-        address outputToken,
+        IERC20TokenV06 outputToken,
         uint256 inputTokenAmount,
         uint256 outputTokenAmount,
         address from,
@@ -70,6 +73,7 @@ contract BridgeAdapter is
         MixinBalancer()
         MixinCurve()
         MixinKyber(addresses)
+        MixinMooniswap(addresses)
         MixinMStable(addresses)
         MixinOasis(addresses)
         MixinUniswap(addresses)
@@ -79,6 +83,7 @@ contract BridgeAdapter is
         BALANCER_BRIDGE_ADDRESS = addresses.balancerBridge;
         CURVE_BRIDGE_ADDRESS = addresses.curveBridge;
         KYBER_BRIDGE_ADDRESS = addresses.kyberBridge;
+        MOONISWAP_BRIDGE_ADDRESS = addresses.mooniswapBridge;
         MSTABLE_BRIDGE_ADDRESS = addresses.mStableBridge;
         OASIS_BRIDGE_ADDRESS = addresses.oasisBridge;
         UNISWAP_BRIDGE_ADDRESS = addresses.uniswapBridge;
@@ -87,19 +92,19 @@ contract BridgeAdapter is
 
     function trade(
         bytes calldata makerAssetData,
-        address fromTokenAddress,
+        IERC20TokenV06 sellToken,
         uint256 sellAmount
     )
         external
         returns (uint256 boughtAmount)
     {
         (
-            address toTokenAddress,
+            IERC20TokenV06 buyToken,
             address bridgeAddress,
             bytes memory bridgeData
         ) = abi.decode(
             makerAssetData[4:],
-            (address, address, bytes)
+            (IERC20TokenV06, address, bytes)
         );
         require(
             bridgeAddress != address(this) && bridgeAddress != address(0),
@@ -108,65 +113,71 @@ contract BridgeAdapter is
 
         if (bridgeAddress == CURVE_BRIDGE_ADDRESS) {
             boughtAmount = _tradeCurve(
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else if (bridgeAddress == UNISWAP_V2_BRIDGE_ADDRESS) {
             boughtAmount = _tradeUniswapV2(
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else if (bridgeAddress == UNISWAP_BRIDGE_ADDRESS) {
             boughtAmount = _tradeUniswap(
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else if (bridgeAddress == BALANCER_BRIDGE_ADDRESS) {
             boughtAmount = _tradeBalancer(
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else if (bridgeAddress == KYBER_BRIDGE_ADDRESS) {
             boughtAmount = _tradeKyber(
-                toTokenAddress,
+                buyToken,
+                sellAmount,
+                bridgeData
+            );
+        } else if (bridgeAddress == MOONISWAP_BRIDGE_ADDRESS) {
+            boughtAmount = _tradeMooniswap(
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else if (bridgeAddress == MSTABLE_BRIDGE_ADDRESS) {
             boughtAmount = _tradeMStable(
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else if (bridgeAddress == OASIS_BRIDGE_ADDRESS) {
             boughtAmount = _tradeOasis(
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
         } else {
             boughtAmount = _tradeZeroExBridge(
                 bridgeAddress,
-                fromTokenAddress,
+                sellToken,
-                toTokenAddress,
+                buyToken,
                 sellAmount,
                 bridgeData
             );
+            // Do not emit an event. The bridge contract should emit one itself.
+            return boughtAmount;
         }
 
         emit ERC20BridgeTransfer(
-            fromTokenAddress,
+            sellToken,
-            toTokenAddress,
+            buyToken,
             sellAmount,
             boughtAmount,
             bridgeAddress,
             address(this)
         );
-
-        return boughtAmount;
     }
 }

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinAdapterAddresses.sol

@@ -26,6 +26,7 @@ contract MixinAdapterAddresses
         address balancerBridge;
         address curveBridge;
         address kyberBridge;
+        address mooniswapBridge;
         address mStableBridge;
         address oasisBridge;
         address uniswapBridge;

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinBalancer.sol

@@ -32,9 +32,9 @@ interface IBalancerPool {
     /// @return spotPriceAfter The new marginal spot price of the given
     ///         token pair for this pool.
     function swapExactAmountIn(
-        address tokenIn,
+        IERC20TokenV06 tokenIn,
         uint tokenAmountIn,
-        address tokenOut,
+        IERC20TokenV06 tokenOut,
         uint minAmountOut,
         uint maxPrice
     ) external returns (uint tokenAmountOut, uint spotPriceAfter);
@@ -45,7 +45,7 @@ contract MixinBalancer {
     using LibERC20TokenV06 for IERC20TokenV06;
 
     function _tradeBalancer(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
@@ -53,19 +53,19 @@ contract MixinBalancer {
         returns (uint256 boughtAmount)
     {
         // Decode the bridge data.
-        (address fromTokenAddress, address poolAddress) = abi.decode(
+        (IERC20TokenV06 sellToken, IBalancerPool pool) = abi.decode(
             bridgeData,
-            (address, address)
+            (IERC20TokenV06, IBalancerPool)
         );
-        IERC20TokenV06(fromTokenAddress).approveIfBelow(
+        sellToken.approveIfBelow(
-            poolAddress,
+            address(pool),
             sellAmount
         );
-        // Sell all of this contract's `fromTokenAddress` token balance.
+        // Sell all of this contract's `sellToken` token balance.
-        (boughtAmount,) = IBalancerPool(poolAddress).swapExactAmountIn(
+        (boughtAmount,) = pool.swapExactAmountIn(
-            fromTokenAddress, // tokenIn
+            sellToken,  // tokenIn
             sellAmount, // tokenAmountIn
-            toTokenAddress,   // tokenOut
+            buyToken,   // tokenOut
             1,          // minAmountOut
             uint256(-1) // maxPrice
         );

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinCurve.sol

@@ -34,13 +34,13 @@ contract MixinCurve {
     struct CurveBridgeData {
         address curveAddress;
         bytes4 exchangeFunctionSelector;
-        address fromTokenAddress;
+        IERC20TokenV06 sellToken;
         int128 fromCoinIdx;
         int128 toCoinIdx;
     }
 
     function _tradeCurve(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
@@ -49,8 +49,8 @@ contract MixinCurve {
     {
         // Decode the bridge data to get the Curve metadata.
         CurveBridgeData memory data = abi.decode(bridgeData, (CurveBridgeData));
-        IERC20TokenV06(data.fromTokenAddress).approveIfBelow(data.curveAddress, sellAmount);
+        data.sellToken.approveIfBelow(data.curveAddress, sellAmount);
-        uint256 beforeBalance = IERC20TokenV06(toTokenAddress).balanceOf(address(this));
+        uint256 beforeBalance = buyToken.balanceOf(address(this));
         (bool success, bytes memory resultData) =
             data.curveAddress.call(abi.encodeWithSelector(
                 data.exchangeFunctionSelector,
@@ -64,7 +64,6 @@ contract MixinCurve {
         if (!success) {
             resultData.rrevert();
         }
-
+        return buyToken.balanceOf(address(this)).safeSub(beforeBalance);
-        return IERC20TokenV06(toTokenAddress).balanceOf(address(this)).safeSub(beforeBalance);
     }
 }

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinKyber.sol

@@ -26,24 +26,27 @@ import "./MixinAdapterAddresses.sol";
 
 interface IKyberNetworkProxy {
 
-    /// @dev Sells `sellTokenAddress` tokens for `buyTokenAddress` tokens.
+    /// @dev Sells `sellTokenAddress` tokens for `buyTokenAddress` tokens
-    /// @param sellTokenAddress Token to sell.
+    /// using a hint for the reserve.
+    /// @param sellToken Token to sell.
     /// @param sellAmount Amount of tokens to sell.
-    /// @param buyTokenAddress Token to buy.
+    /// @param buyToken Token to buy.
     /// @param recipientAddress Address to send bought tokens to.
     /// @param maxBuyTokenAmount A limit on the amount of tokens to buy.
     /// @param minConversionRate The minimal conversion rate. If actual rate
     ///        is lower, trade is canceled.
     /// @param walletId The wallet ID to send part of the fees
+    /// @param hint The hint for the selective inclusion (or exclusion) of reserves
     /// @return boughtAmount Amount of tokens bought.
-    function trade(
+    function tradeWithHint(
-        address sellTokenAddress,
+        IERC20TokenV06 sellToken,
         uint256 sellAmount,
-        address buyTokenAddress,
+        IERC20TokenV06 buyToken,
         address payable recipientAddress,
         uint256 maxBuyTokenAmount,
         uint256 minConversionRate,
-        address walletId
+        address payable walletId,
+        bytes calldata hint
     )
         external
         payable
@@ -53,7 +56,6 @@ interface IKyberNetworkProxy {
 contract MixinKyber is
     MixinAdapterAddresses
 {
-
     using LibERC20TokenV06 for IERC20TokenV06;
 
     /// @dev Address indicating the trade is using ETH
@@ -71,41 +73,39 @@ contract MixinKyber is
     }
 
     function _tradeKyber(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
         internal
         returns (uint256 boughtAmount)
     {
-        // Decode the bridge data to get the `fromTokenAddress`.
+        (IERC20TokenV06 sellToken, bytes memory hint) =
-        address fromTokenAddress = abi.decode(bridgeData, (address));
+            abi.decode(bridgeData, (IERC20TokenV06, bytes));
-        uint256 payableAmount;
 
-        if (fromTokenAddress != address(WETH)) {
+        uint256 payableAmount = 0;
+        if (sellToken != WETH) {
             // If the input token is not WETH, grant an allowance to the exchange
             // to spend them.
-            IERC20TokenV06(fromTokenAddress).approveIfBelow(
+            sellToken.approveIfBelow(
                 address(KYBER_NETWORK_PROXY),
                 sellAmount
             );
         } else {
             // If the input token is WETH, unwrap it and attach it to the call.
-            fromTokenAddress = KYBER_ETH_ADDRESS;
             payableAmount = sellAmount;
             WETH.withdraw(payableAmount);
         }
-        bool isToTokenWeth = toTokenAddress == address(WETH);
 
         // Try to sell all of this contract's input token balance through
         // `KyberNetworkProxy.trade()`.
-        boughtAmount = KYBER_NETWORK_PROXY.trade{ value: payableAmount }(
+        boughtAmount = KYBER_NETWORK_PROXY.tradeWithHint{ value: payableAmount }(
             // Input token.
-            fromTokenAddress,
+            sellToken == WETH ? IERC20TokenV06(KYBER_ETH_ADDRESS) : sellToken,
             // Sell amount.
             sellAmount,
             // Output token.
-            isToTokenWeth ? KYBER_ETH_ADDRESS : toTokenAddress,
+            buyToken == WETH ? IERC20TokenV06(KYBER_ETH_ADDRESS) : buyToken,
             // Transfer to this contract
             address(uint160(address(this))),
             // Buy as much as possible.
@@ -113,9 +113,11 @@ contract MixinKyber is
             // Lowest minimum conversion rate
             1,
             // No affiliate address.
-            address(0)
+            address(0),
+            hint
         );
-        if (isToTokenWeth) {
+        // If receving ETH, wrap it to WETH.
+        if (buyToken == WETH) {
             WETH.deposit{ value: boughtAmount }();
         }
         return boughtAmount;

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinMStable.sol

@@ -27,19 +27,18 @@ import "./MixinAdapterAddresses.sol";
 interface IMStable {
 
     function swap(
-        address _input,
+        IERC20TokenV06 sellToken,
-        address _output,
+        IERC20TokenV06 buyToken,
-        uint256 _quantity,
+        uint256 sellAmount,
-        address _recipient
+        address recipient
     )
         external
-        returns (uint256 output);
+        returns (uint256 boughtAmount);
 }
 
 contract MixinMStable is
     MixinAdapterAddresses
 {
-
     using LibERC20TokenV06 for IERC20TokenV06;
 
     /// @dev Mainnet address of the mStable mUSD contract.
@@ -52,21 +51,21 @@ contract MixinMStable is
     }
 
     function _tradeMStable(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
         internal
         returns (uint256 boughtAmount)
     {
-        // Decode the bridge data to get the `fromTokenAddress`.
+        // Decode the bridge data to get the `sellToken`.
-        (address fromTokenAddress) = abi.decode(bridgeData, (address));
+        (IERC20TokenV06 sellToken) = abi.decode(bridgeData, (IERC20TokenV06));
-        // Grant an allowance to the exchange to spend `fromTokenAddress` token.
+        // Grant an allowance to the exchange to spend `sellToken` token.
-        IERC20TokenV06(fromTokenAddress).approveIfBelow(address(MSTABLE), sellAmount);
+        sellToken.approveIfBelow(address(MSTABLE), sellAmount);
 
         boughtAmount = MSTABLE.swap(
-            fromTokenAddress,
+            sellToken,
-            toTokenAddress,
+            buyToken,
             sellAmount,
             address(this)
         );

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinMooniswap.sol

@@ -0,0 +1,97 @@
+
+/*
+
+  Copyright 2020 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 ^0.6.5;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
+import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
+import "@0x/contracts-erc20/contracts/src/v06/IEtherTokenV06.sol";
+import "./MixinAdapterAddresses.sol";
+
+
+/// @dev Moooniswap pool interface.
+interface IMooniswapPool {
+
+    function swap(
+        IERC20TokenV06 sellToken,
+        IERC20TokenV06 buyToken,
+        uint256 sellAmount,
+        uint256 minBoughtAmount,
+        address referrer
+    )
+        external
+        payable
+        returns (uint256 boughtAmount);
+}
+
+/// @dev BridgeAdapter mixin for mooniswap.
+contract MixinMooniswap is
+    MixinAdapterAddresses
+{
+    using LibERC20TokenV06 for IERC20TokenV06;
+    using LibERC20TokenV06 for IEtherTokenV06;
+
+    /// @dev WETH token.
+    IEtherTokenV06 private immutable WETH;
+
+    constructor(AdapterAddresses memory addresses)
+        public
+    {
+        WETH = IEtherTokenV06(addresses.weth);
+    }
+
+    function _tradeMooniswap(
+        IERC20TokenV06 buyToken,
+        uint256 sellAmount,
+        bytes memory bridgeData
+    )
+        internal
+        returns (uint256 boughtAmount)
+    {
+        (IERC20TokenV06 sellToken, IMooniswapPool pool) =
+            abi.decode(bridgeData, (IERC20TokenV06, IMooniswapPool));
+
+        // Convert WETH to ETH.
+        uint256 ethValue = 0;
+        if (sellToken == WETH) {
+            WETH.withdraw(sellAmount);
+            ethValue = sellAmount;
+        } else {
+            // Grant the pool an allowance.
+            sellToken.approveIfBelow(
+                address(pool),
+                sellAmount
+            );
+        }
+
+        boughtAmount = pool.swap{value: ethValue}(
+            sellToken == WETH ? IERC20TokenV06(0) : sellToken,
+            buyToken == WETH ? IERC20TokenV06(0) : buyToken,
+            sellAmount,
+            1,
+            address(0)
+        );
+
+        // Wrap ETH to WETH.
+        if (buyToken == WETH) {
+            WETH.deposit{value:boughtAmount}();
+        }
+    }
+}

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinOasis.sol

@@ -25,26 +25,25 @@ import "./MixinAdapterAddresses.sol";
 
 interface IOasis {
 
-    /// @dev Sell `sellAmount` of `fromToken` token and receive `toToken` token.
+    /// @dev Sell `sellAmount` of `sellToken` token and receive `buyToken` token.
-    /// @param fromToken The token being sold.
+    /// @param sellToken The token being sold.
-    /// @param sellAmount The amount of `fromToken` token being sold.
+    /// @param sellAmount The amount of `sellToken` token being sold.
-    /// @param toToken The token being bought.
+    /// @param buyToken The token being bought.
-    /// @param minFillAmount Minimum amount of `toToken` token to buy.
+    /// @param minBoughtAmount Minimum amount of `buyToken` token to buy.
-    /// @return fillAmount Amount of `toToken` bought.
+    /// @return boughtAmount Amount of `buyToken` bought.
     function sellAllAmount(
-        address fromToken,
+        IERC20TokenV06 sellToken,
         uint256 sellAmount,
-        address toToken,
+        IERC20TokenV06 buyToken,
-        uint256 minFillAmount
+        uint256 minBoughtAmount
     )
         external
-        returns (uint256 fillAmount);
+        returns (uint256 boughtAmount);
 }
 
 contract MixinOasis is
     MixinAdapterAddresses
 {
-
     using LibERC20TokenV06 for IERC20TokenV06;
 
     /// @dev Mainnet address of the Oasis `MatchingMarket` contract.
@@ -57,25 +56,25 @@ contract MixinOasis is
     }
 
     function _tradeOasis(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
         internal
         returns (uint256 boughtAmount)
     {
-        // Decode the bridge data to get the `fromTokenAddress`.
+        // Decode the bridge data to get the `sellToken`.
-        (address fromTokenAddress) = abi.decode(bridgeData, (address));
+        (IERC20TokenV06 sellToken) = abi.decode(bridgeData, (IERC20TokenV06));
-        // Grant an allowance to the exchange to spend `fromTokenAddress` token.
+        // Grant an allowance to the exchange to spend `sellToken` token.
-        IERC20TokenV06(fromTokenAddress).approveIfBelow(
+        sellToken.approveIfBelow(
             address(OASIS),
             sellAmount
         );
-        // Try to sell all of this contract's `fromTokenAddress` token balance.
+        // Try to sell all of this contract's `sellToken` token balance.
         boughtAmount = OASIS.sellAllAmount(
-            fromTokenAddress,
+            sellToken,
             sellAmount,
-            toTokenAddress,
+            buyToken,
             // min fill amount
             1
         );

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinUniswap.sol

@@ -27,11 +27,11 @@ import "./MixinAdapterAddresses.sol";
 interface IUniswapExchangeFactory {
 
     /// @dev Get the exchange for a token.
-    /// @param tokenAddress The address of the token contract.
+    /// @param token The token contract.
-    function getExchange(address tokenAddress)
+    function getExchange(IERC20TokenV06 token)
         external
         view
-        returns (address);
+        returns (IUniswapExchange exchange);
 }
 
 interface IUniswapExchange {
@@ -71,7 +71,7 @@ interface IUniswapExchange {
     /// @param minEthBought The minimum amount of intermediate ETH to buy.
     /// @param deadline Time when this order expires.
     /// @param recipient Who to transfer the tokens to.
-    /// @param toTokenAddress The token being bought.
+    /// @param buyToken The token being bought.
     /// @return tokensBought Amount of tokens bought.
     function tokenToTokenTransferInput(
         uint256 tokensSold,
@@ -79,7 +79,7 @@ interface IUniswapExchange {
         uint256 minEthBought,
         uint256 deadline,
         address recipient,
-        address toTokenAddress
+        IERC20TokenV06 buyToken
     )
         external
         returns (uint256 tokensBought);
@@ -89,14 +89,14 @@ interface IUniswapExchange {
     /// @param minTokensBought The minimum number of tokens to buy.
     /// @param minEthBought The minimum amount of intermediate ETH to buy.
     /// @param deadline Time when this order expires.
-    /// @param toTokenAddress The token being bought.
+    /// @param buyToken The token being bought.
     /// @return tokensBought Amount of tokens bought.
     function tokenToTokenSwapInput(
         uint256 tokensSold,
         uint256 minTokensBought,
         uint256 minEthBought,
         uint256 deadline,
-        address toTokenAddress
+        IERC20TokenV06 buyToken
     )
         external
         returns (uint256 tokensBought);
@@ -105,7 +105,6 @@ interface IUniswapExchange {
 contract MixinUniswap is
     MixinAdapterAddresses
 {
-
     using LibERC20TokenV06 for IERC20TokenV06;
 
     /// @dev Mainnet address of the WETH contract.
@@ -121,27 +120,27 @@ contract MixinUniswap is
     }
 
     function _tradeUniswap(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
         internal
         returns (uint256 boughtAmount)
     {
-        // Decode the bridge data to get the `fromTokenAddress`.
+        // Decode the bridge data to get the `sellToken`.
-        (address fromTokenAddress) = abi.decode(bridgeData, (address));
+        (IERC20TokenV06 sellToken) = abi.decode(bridgeData, (IERC20TokenV06));
 
         // Get the exchange for the token pair.
         IUniswapExchange exchange = _getUniswapExchangeForTokenPair(
-            fromTokenAddress,
+            sellToken,
-            toTokenAddress
+            buyToken
         );
 
         // Convert from WETH to a token.
-        if (fromTokenAddress == address(WETH)) {
+        if (sellToken == WETH) {
             // Unwrap the WETH.
             WETH.withdraw(sellAmount);
-            // Buy as much of `toTokenAddress` token with ETH as possible
+            // Buy as much of `buyToken` token with ETH as possible
             boughtAmount = exchange.ethToTokenTransferInput{ value: sellAmount }(
                 // Minimum buy amount.
                 1,
@@ -152,13 +151,13 @@ contract MixinUniswap is
             );
 
         // Convert from a token to WETH.
-        } else if (toTokenAddress == address(WETH)) {
+        } else if (buyToken == WETH) {
             // Grant the exchange an allowance.
-            IERC20TokenV06(fromTokenAddress).approveIfBelow(
+            sellToken.approveIfBelow(
                 address(exchange),
                 sellAmount
             );
-            // Buy as much ETH with `fromTokenAddress` token as possible.
+            // Buy as much ETH with `sellToken` token as possible.
             boughtAmount = exchange.tokenToEthSwapInput(
                 // Sell all tokens we hold.
                 sellAmount,
@@ -172,11 +171,11 @@ contract MixinUniswap is
         // Convert from one token to another.
         } else {
             // Grant the exchange an allowance.
-            IERC20TokenV06(fromTokenAddress).approveIfBelow(
+            sellToken.approveIfBelow(
                 address(exchange),
                 sellAmount
             );
-            // Buy as much `toTokenAddress` token with `fromTokenAddress` token
+            // Buy as much `buyToken` token with `sellToken` token
             boughtAmount = exchange.tokenToTokenSwapInput(
                 // Sell all tokens we hold.
                 sellAmount,
@@ -186,8 +185,8 @@ contract MixinUniswap is
                 1,
                 // Expires after this block.
                 block.timestamp,
-                // Convert to `toTokenAddress`.
+                // Convert to `buyToken`.
-                toTokenAddress
+                buyToken
             );
         }
 
@@ -197,24 +196,21 @@ contract MixinUniswap is
     /// @dev Retrieves the uniswap exchange for a given token pair.
     ///      In the case of a WETH-token exchange, this will be the non-WETH token.
     ///      In th ecase of a token-token exchange, this will be the first token.
-    /// @param fromTokenAddress The address of the token we are converting from.
+    /// @param sellToken The address of the token we are converting from.
-    /// @param toTokenAddress The address of the token we are converting to.
+    /// @param buyToken The address of the token we are converting to.
     /// @return exchange The uniswap exchange.
     function _getUniswapExchangeForTokenPair(
-        address fromTokenAddress,
+        IERC20TokenV06 sellToken,
-        address toTokenAddress
+        IERC20TokenV06 buyToken
     )
         private
         view
         returns (IUniswapExchange exchange)
     {
-        address exchangeTokenAddress = fromTokenAddress;
         // Whichever isn't WETH is the exchange token.
-        if (fromTokenAddress == address(WETH)) {
+        exchange = sellToken == WETH
-            exchangeTokenAddress = toTokenAddress;
+            ? UNISWAP_EXCHANGE_FACTORY.getExchange(buyToken)
-        }
+            : UNISWAP_EXCHANGE_FACTORY.getExchange(sellToken);
-        exchange = IUniswapExchange(UNISWAP_EXCHANGE_FACTORY.getExchange(exchangeTokenAddress));
         require(address(exchange) != address(0), "NO_UNISWAP_EXCHANGE_FOR_TOKEN");
-        return exchange;
     }
 }

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinUniswapV2.sol

@@ -50,7 +50,6 @@ interface IUniswapV2Router02 {
 contract MixinUniswapV2 is
     MixinAdapterAddresses
 {
-
     using LibERC20TokenV06 for IERC20TokenV06;
 
     /// @dev Mainnet address of the `UniswapV2Router02` contract.
@@ -63,21 +62,23 @@ contract MixinUniswapV2 is
     }
 
     function _tradeUniswapV2(
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
         internal
-        returns (uint256)
+        returns (uint256 boughtAmount)
     {
-        // Decode the bridge data to get the `fromTokenAddress`.
         // solhint-disable indent
         address[] memory path = abi.decode(bridgeData, (address[]));
         // solhint-enable indent
 
         require(path.length >= 2, "UniswapV2Bridge/PATH_LENGTH_MUST_BE_AT_LEAST_TWO");
-        require(path[path.length - 1] == toTokenAddress, "UniswapV2Bridge/LAST_ELEMENT_OF_PATH_MUST_MATCH_OUTPUT_TOKEN");
+        require(
-        // Grant the Uniswap router an allowance.
+            path[path.length - 1] == address(buyToken),
+            "UniswapV2Bridge/LAST_ELEMENT_OF_PATH_MUST_MATCH_OUTPUT_TOKEN"
+        );
+        // Grant the Uniswap router an allowance to sell the first token.
         IERC20TokenV06(path[0]).approveIfBelow(
             address(UNISWAP_V2_ROUTER),
             sellAmount
@@ -88,7 +89,7 @@ contract MixinUniswapV2 is
             sellAmount,
              // Minimum buy amount.
             1,
-            // Convert `fromTokenAddress` to `toTokenAddress`.
+            // Convert to `buyToken` along this path.
             path,
             // Recipient is `this`.
             address(this),

contracts/zero-ex/contracts/src/transformers/bridges/mixins/MixinZeroExBridge.sol

@@ -24,15 +24,15 @@ import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
 
 interface IERC20Bridge {
 
-    /// @dev Transfers `amount` of the ERC20 `tokenAddress` from `from` to `to`.
+    /// @dev Transfers `amount` of the ERC20 `buyToken` from `from` to `to`.
-    /// @param tokenAddress The address of the ERC20 token to transfer.
+    /// @param buyToken The address of the ERC20 token to transfer.
     /// @param from Address to transfer asset from.
     /// @param to Address to transfer asset to.
     /// @param amount Amount of asset to transfer.
     /// @param bridgeData Arbitrary asset data needed by the bridge contract.
     /// @return success The magic bytes `0xdc1600f3` if successful.
     function bridgeTransferFrom(
-        address tokenAddress,
+        IERC20TokenV06 buyToken,
         address from,
         address to,
         uint256 amount,
@@ -49,28 +49,27 @@ contract MixinZeroExBridge {
 
     function _tradeZeroExBridge(
         address bridgeAddress,
-        address fromTokenAddress,
+        IERC20TokenV06 sellToken,
-        address toTokenAddress,
+        IERC20TokenV06 buyToken,
         uint256 sellAmount,
         bytes memory bridgeData
     )
         internal
         returns (uint256 boughtAmount)
     {
-        uint256 balanceBefore = IERC20TokenV06(toTokenAddress).balanceOf(address(this));
+        uint256 balanceBefore = buyToken.balanceOf(address(this));
         // Trade the good old fashioned way
-        IERC20TokenV06(fromTokenAddress).compatTransfer(
+        sellToken.compatTransfer(
             bridgeAddress,
             sellAmount
         );
         IERC20Bridge(bridgeAddress).bridgeTransferFrom(
-            toTokenAddress,
+            buyToken,
-            bridgeAddress,
+            address(bridgeAddress),
             address(this),
             1, // amount to transfer back from the bridge
             bridgeData
         );
-
+        boughtAmount = buyToken.balanceOf(address(this)).safeSub(balanceBefore);
-        boughtAmount = IERC20TokenV06(toTokenAddress).balanceOf(address(this)).safeSub(balanceBefore);
     }
 }

contracts/zero-ex/contracts/test/TestFillQuoteTransformerHost.sol

@@ -31,6 +31,8 @@ contract TestFillQuoteTransformerHost is
         IERC20Transformer transformer,
         TestMintableERC20Token inputToken,
         uint256 inputTokenAmount,
+        address payable sender,
+        address payable taker,
         bytes calldata data
     )
         external
@@ -40,6 +42,14 @@ contract TestFillQuoteTransformerHost is
             inputToken.mint(address(this), inputTokenAmount);
         }
         // Have to make this call externally because transformers aren't payable.
-        this.rawExecuteTransform(transformer, bytes32(0), msg.sender, data);
+        this.rawExecuteTransform(
+            transformer,
+            IERC20Transformer.TransformContext({
+                callDataHash: bytes32(0),
+                sender: sender,
+                taker: taker,
+                data: data
+            })
+        );
     }
 }

contracts/zero-ex/contracts/test/TestFullMigration.sol

@@ -20,7 +20,6 @@ pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
 import "../src/ZeroEx.sol";
-import "../src/features/IBootstrap.sol";
 import "../src/migrations/FullMigration.sol";
 
 

contracts/zero-ex/contracts/test/TestInitialMigration.sol

@@ -20,7 +20,7 @@ pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
 import "../src/ZeroEx.sol";
-import "../src/features/IBootstrap.sol";
+import "../src/features/IBootstrapFeature.sol";
 import "../src/migrations/InitialMigration.sol";
 
 
@@ -34,7 +34,7 @@ contract TestInitialMigration is
     constructor(address deployer) public InitialMigration(deployer) {}
 
     function callBootstrap(ZeroEx zeroEx) external {
-        IBootstrap(address(zeroEx)).bootstrap(address(this), new bytes(0));
+        IBootstrapFeature(address(zeroEx)).bootstrap(address(this), new bytes(0));
     }
 
     function bootstrap(address owner, BootstrapFeatures memory features)
@@ -45,7 +45,7 @@ contract TestInitialMigration is
         success = InitialMigration.bootstrap(owner, features);
         // Snoop the bootstrap feature contract.
         bootstrapFeature = ZeroEx(address(uint160(address(this))))
-            .getFunctionImplementation(IBootstrap.bootstrap.selector);
+            .getFunctionImplementation(IBootstrapFeature.bootstrap.selector);
     }
 
     function die(address payable ethRecipient) public override {

contracts/zero-ex/contracts/test/TestMetaTransactionsTransformERC20Feature.sol

@@ -19,11 +19,12 @@
 pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
-import "../src/features/TransformERC20.sol";
+import "../src/features/TransformERC20Feature.sol";
+import "../src/features/IMetaTransactionsFeature.sol";
 
 
 contract TestMetaTransactionsTransformERC20Feature is
-    TransformERC20
+    TransformERC20Feature
 {
     event TransformERC20Called(
         address sender,
@@ -48,6 +49,49 @@ contract TestMetaTransactionsTransformERC20Feature is
             revert('FAIL');
         }
 
+        if (msg.value == 777) {
+            // Try to reenter `executeMetaTransaction()`
+            IMetaTransactionsFeature(address(this)).executeMetaTransaction(
+                IMetaTransactionsFeature.MetaTransactionData({
+                    signer: address(0),
+                    sender: address(0),
+                    minGasPrice: 0,
+                    maxGasPrice: 0,
+                    expirationTimeSeconds: 0,
+                    salt: 0,
+                    callData: "",
+                    value: 0,
+                    feeToken: IERC20TokenV06(0),
+                    feeAmount: 0
+                }),
+                ""
+            );
+        }
+
+        if (msg.value == 888) {
+            // Try to reenter `batchExecuteMetaTransactions()`
+            IMetaTransactionsFeature.MetaTransactionData[] memory mtxs =
+                new IMetaTransactionsFeature.MetaTransactionData[](1);
+            bytes[] memory signatures = new bytes[](1);
+            mtxs[0] = IMetaTransactionsFeature.MetaTransactionData({
+                signer: address(0),
+                sender: address(0),
+                minGasPrice: 0,
+                maxGasPrice: 0,
+                expirationTimeSeconds: 0,
+                salt: 0,
+                callData: "",
+                value: 0,
+                feeToken: IERC20TokenV06(0),
+                feeAmount: 0
+            });
+            signatures[0] = "";
+            IMetaTransactionsFeature(address(this)).batchExecuteMetaTransactions(
+                mtxs,
+                signatures
+            );
+        }
+
         emit TransformERC20Called(
             msg.sender,
             msg.value,

contracts/zero-ex/contracts/test/TestMigrator.sol

@@ -20,7 +20,7 @@ pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
 import "../src/migrations/LibMigrate.sol";
-import "../src/features/IOwnable.sol";
+import "../src/features/IOwnableFeature.sol";
 
 
 contract TestMigrator {
@@ -32,7 +32,7 @@ contract TestMigrator {
     function succeedingMigrate() external returns (bytes4 success) {
         emit TestMigrateCalled(
             msg.data,
-            IOwnable(address(this)).owner()
+            IOwnableFeature(address(this)).owner()
         );
         return LibMigrate.MIGRATE_SUCCESS;
     }
@@ -40,7 +40,7 @@ contract TestMigrator {
     function failingMigrate() external returns (bytes4 success) {
         emit TestMigrateCalled(
             msg.data,
-            IOwnable(address(this)).owner()
+            IOwnableFeature(address(this)).owner()
         );
         return 0xdeadbeef;
     }

contracts/zero-ex/contracts/test/TestMintTokenERC20Transformer.sol

@@ -40,28 +40,26 @@ contract TestMintTokenERC20Transformer is
         address context,
         address caller,
         bytes32 callDataHash,
+        address sender,
         address taker,
         bytes data,
         uint256 inputTokenBalance,
         uint256 ethBalance
     );
 
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32 callDataHash,
-        address payable taker,
-        bytes calldata data_
-    )
         external
         override
         returns (bytes4 success)
     {
-        TransformData memory data = abi.decode(data_, (TransformData));
+        TransformData memory data = abi.decode(context.data, (TransformData));
         emit MintTransform(
             address(this),
             msg.sender,
-            callDataHash,
+            context.callDataHash,
-            taker,
+            context.sender,
-            data_,
+            context.taker,
+            context.data,
             data.inputToken.balanceOf(address(this)),
             address(this).balance
         );
@@ -69,14 +67,14 @@ contract TestMintTokenERC20Transformer is
         data.inputToken.transfer(address(0), data.burnAmount);
         // Mint output tokens.
         if (LibERC20Transformer.isTokenETH(IERC20TokenV06(address(data.outputToken)))) {
-            taker.transfer(data.mintAmount);
+            context.taker.transfer(data.mintAmount);
         } else {
             data.outputToken.mint(
-                taker,
+                context.taker,
                 data.mintAmount
             );
             // Burn fees from output.
-            data.outputToken.burn(taker, data.feeAmount);
+            data.outputToken.burn(context.taker, data.feeAmount);
         }
         return LibERC20Transformer.TRANSFORMER_SUCCESS;
     }

contracts/zero-ex/contracts/test/TestTokenSpender.sol

@@ -19,10 +19,10 @@
 pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
-import "../src/features/TokenSpender.sol";
+import "../src/features/TokenSpenderFeature.sol";
 
 contract TestTokenSpender is
-    TokenSpender
+    TokenSpenderFeature
 {
     modifier onlySelf() override {
         _;

contracts/zero-ex/contracts/test/TestTransformERC20.sol

@@ -19,18 +19,12 @@
 pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
-import "../src/features/TransformERC20.sol";
+import "../src/features/TransformERC20Feature.sol";
 
 
 contract TestTransformERC20 is
-    TransformERC20
+    TransformERC20Feature
 {
-    // solhint-disable no-empty-blocks
-    constructor()
-        TransformERC20()
-        public
-    {}
-
     modifier onlySelf() override {
         _;
     }

contracts/zero-ex/contracts/test/TestTransformerBase.sol

@@ -20,17 +20,15 @@ pragma solidity ^0.6.5;
 pragma experimental ABIEncoderV2;
 
 import "../src/transformers/Transformer.sol";
+import "../src/transformers/IERC20Transformer.sol";
 import "../src/transformers/LibERC20Transformer.sol";
 
 
 contract TestTransformerBase is
+    IERC20Transformer,
     Transformer
 {
-    function transform(
+    function transform(TransformContext calldata context)
-        bytes32,
-        address payable,
-        bytes calldata
-    )
         external
         override
         returns (bytes4 success)

contracts/zero-ex/contracts/test/TestTransformerDeployerTransformer.sol

@@ -24,10 +24,15 @@ import "../src/transformers/LibERC20Transformer.sol";
 
 contract TestTransformerDeployerTransformer {
 
+    uint256 public constant CONSTRUCTOR_FAIL_VALUE = 3333;
     address payable public immutable deployer;
 
     constructor() public payable {
         deployer = msg.sender;
+        require(
+            msg.value != CONSTRUCTOR_FAIL_VALUE,
+            "TestTransformerDeployerTransformer/CONSTRUCTOR_FAIL"
+        );
     }
 
     modifier onlyDeployer() {
@@ -35,11 +40,11 @@ contract TestTransformerDeployerTransformer {
         _;
     }
 
-    function die()
+    function die(address payable ethRecipient)
         external
         onlyDeployer
     {
-        selfdestruct(deployer);
+        selfdestruct(ethRecipient);
     }
 
     function isDeployedByDeployer(uint32 nonce)

contracts/zero-ex/contracts/test/TestTransformerHost.sol

@@ -32,18 +32,14 @@ contract TestTransformerHost {
 
     function rawExecuteTransform(
         IERC20Transformer transformer,
-        bytes32 callDataHash,
+        IERC20Transformer.TransformContext calldata context
-        address taker,
-        bytes calldata data
     )
         external
     {
         (bool _success, bytes memory resultData) =
             address(transformer).delegatecall(abi.encodeWithSelector(
                 transformer.transform.selector,
-                callDataHash,
+                context
-                taker,
-                data
             ));
         if (!_success) {
             resultData.rrevert();

contracts/zero-ex/contracts/test/TestWethTransformerHost.sol

@@ -48,6 +48,14 @@ contract TestWethTransformerHost is
             _weth.deposit{value: wethAmount}();
         }
         // Have to make this call externally because transformers aren't payable.
-        this.rawExecuteTransform(transformer, bytes32(0), msg.sender, data);
+        this.rawExecuteTransform(
+            transformer,
+            IERC20Transformer.TransformContext({
+                callDataHash: bytes32(0),
+                sender: msg.sender,
+                taker: msg.sender,
+                data: data
+            })
+        );
     }
 }

contracts/zero-ex/package.json

@@ -39,9 +39,9 @@
         "publish:private": "yarn build && gitpkg publish"
     },
     "config": {
-        "publicInterfaceContracts": "IZeroEx,ZeroEx,FullMigration,InitialMigration,IFlashWallet,IAllowanceTarget,IERC20Transformer,IOwnable,ISimpleFunctionRegistry,ITokenSpender,ITransformERC20,FillQuoteTransformer,PayTakerTransformer,WethTransformer,Ownable,SimpleFunctionRegistry,TransformERC20,TokenSpender,AffiliateFeeTransformer,SignatureValidator,MetaTransactions,BridgeAdapter",
+        "publicInterfaceContracts": "IZeroEx,ZeroEx,FullMigration,InitialMigration,IFlashWallet,IAllowanceTarget,IERC20Transformer,IOwnableFeature,ISimpleFunctionRegistryFeature,ITokenSpenderFeature,ITransformERC20Feature,FillQuoteTransformer,PayTakerTransformer,WethTransformer,OwnableFeature,SimpleFunctionRegistryFeature,TransformERC20Feature,TokenSpenderFeature,AffiliateFeeTransformer,SignatureValidatorFeature,MetaTransactionsFeature,LogMetadataTransformer,BridgeAdapter",
         "abis:comment": "This list is auto-generated by contracts-gen. Don't edit manually.",
-        "abis": "./test/generated-artifacts/@(AffiliateFeeTransformer|AllowanceTarget|Bootstrap|BridgeAdapter|FillQuoteTransformer|FixinCommon|FixinEIP712|FlashWallet|FullMigration|IAllowanceTarget|IBootstrap|IBridgeAdapter|IERC20Bridge|IERC20Transformer|IExchange|IFeature|IFlashWallet|IGasToken|IMetaTransactions|IOwnable|ISignatureValidator|ISimpleFunctionRegistry|ITestSimpleFunctionRegistryFeature|ITokenSpender|ITransformERC20|IZeroEx|InitialMigration|LibBootstrap|LibCommonRichErrors|LibERC20Transformer|LibMetaTransactionsRichErrors|LibMetaTransactionsStorage|LibMigrate|LibOwnableRichErrors|LibOwnableStorage|LibProxyRichErrors|LibProxyStorage|LibSignatureRichErrors|LibSignedCallData|LibSimpleFunctionRegistryRichErrors|LibSimpleFunctionRegistryStorage|LibSpenderRichErrors|LibStorage|LibTokenSpenderStorage|LibTransformERC20RichErrors|LibTransformERC20Storage|LibWalletRichErrors|MetaTransactions|MixinAdapterAddresses|MixinBalancer|MixinCurve|MixinKyber|MixinMStable|MixinOasis|MixinUniswap|MixinUniswapV2|MixinZeroExBridge|Ownable|PayTakerTransformer|SignatureValidator|SimpleFunctionRegistry|TestCallTarget|TestDelegateCaller|TestFillQuoteTransformerBridge|TestFillQuoteTransformerExchange|TestFillQuoteTransformerHost|TestFullMigration|TestInitialMigration|TestMetaTransactionsTransformERC20Feature|TestMigrator|TestMintTokenERC20Transformer|TestMintableERC20Token|TestSimpleFunctionRegistryFeatureImpl1|TestSimpleFunctionRegistryFeatureImpl2|TestTokenSpender|TestTokenSpenderERC20Token|TestTransformERC20|TestTransformerBase|TestTransformerDeployerTransformer|TestTransformerHost|TestWeth|TestWethTransformerHost|TestZeroExFeature|TokenSpender|TransformERC20|Transformer|TransformerDeployer|WethTransformer|ZeroEx).json"
+        "abis": "./test/generated-artifacts/@(AffiliateFeeTransformer|AllowanceTarget|BootstrapFeature|BridgeAdapter|FillQuoteTransformer|FixinCommon|FixinEIP712|FixinReentrancyGuard|FlashWallet|FullMigration|IAllowanceTarget|IBootstrapFeature|IBridgeAdapter|IERC20Bridge|IERC20Transformer|IExchange|IFeature|IFlashWallet|IGasToken|IMetaTransactionsFeature|IOwnableFeature|ISignatureValidatorFeature|ISimpleFunctionRegistryFeature|ITestSimpleFunctionRegistryFeature|ITokenSpenderFeature|ITransformERC20Feature|IZeroEx|InitialMigration|LibBootstrap|LibCommonRichErrors|LibERC20Transformer|LibMetaTransactionsRichErrors|LibMetaTransactionsStorage|LibMigrate|LibOwnableRichErrors|LibOwnableStorage|LibProxyRichErrors|LibProxyStorage|LibReentrancyGuardStorage|LibSignatureRichErrors|LibSignedCallData|LibSimpleFunctionRegistryRichErrors|LibSimpleFunctionRegistryStorage|LibSpenderRichErrors|LibStorage|LibTokenSpenderStorage|LibTransformERC20RichErrors|LibTransformERC20Storage|LibWalletRichErrors|LogMetadataTransformer|MetaTransactionsFeature|MixinAdapterAddresses|MixinBalancer|MixinCurve|MixinKyber|MixinMStable|MixinMooniswap|MixinOasis|MixinUniswap|MixinUniswapV2|MixinZeroExBridge|OwnableFeature|PayTakerTransformer|SignatureValidatorFeature|SimpleFunctionRegistryFeature|TestCallTarget|TestDelegateCaller|TestFillQuoteTransformerBridge|TestFillQuoteTransformerExchange|TestFillQuoteTransformerHost|TestFullMigration|TestInitialMigration|TestMetaTransactionsTransformERC20Feature|TestMigrator|TestMintTokenERC20Transformer|TestMintableERC20Token|TestSimpleFunctionRegistryFeatureImpl1|TestSimpleFunctionRegistryFeatureImpl2|TestTokenSpender|TestTokenSpenderERC20Token|TestTransformERC20|TestTransformerBase|TestTransformerDeployerTransformer|TestTransformerHost|TestWeth|TestWethTransformerHost|TestZeroExFeature|TokenSpenderFeature|TransformERC20Feature|Transformer|TransformerDeployer|WethTransformer|ZeroEx).json"
     },
     "repository": {
         "type": "git",

contracts/zero-ex/src/artifacts.ts

@@ -13,18 +13,19 @@ import * as IAllowanceTarget from '../generated-artifacts/IAllowanceTarget.json'
 import * as IERC20Transformer from '../generated-artifacts/IERC20Transformer.json';
 import * as IFlashWallet from '../generated-artifacts/IFlashWallet.json';
 import * as InitialMigration from '../generated-artifacts/InitialMigration.json';
-import * as IOwnable from '../generated-artifacts/IOwnable.json';
+import * as IOwnableFeature from '../generated-artifacts/IOwnableFeature.json';
-import * as ISimpleFunctionRegistry from '../generated-artifacts/ISimpleFunctionRegistry.json';
+import * as ISimpleFunctionRegistryFeature from '../generated-artifacts/ISimpleFunctionRegistryFeature.json';
-import * as ITokenSpender from '../generated-artifacts/ITokenSpender.json';
+import * as ITokenSpenderFeature from '../generated-artifacts/ITokenSpenderFeature.json';
-import * as ITransformERC20 from '../generated-artifacts/ITransformERC20.json';
+import * as ITransformERC20Feature from '../generated-artifacts/ITransformERC20Feature.json';
 import * as IZeroEx from '../generated-artifacts/IZeroEx.json';
-import * as MetaTransactions from '../generated-artifacts/MetaTransactions.json';
+import * as LogMetadataTransformer from '../generated-artifacts/LogMetadataTransformer.json';
-import * as Ownable from '../generated-artifacts/Ownable.json';
+import * as MetaTransactionsFeature from '../generated-artifacts/MetaTransactionsFeature.json';
+import * as OwnableFeature from '../generated-artifacts/OwnableFeature.json';
 import * as PayTakerTransformer from '../generated-artifacts/PayTakerTransformer.json';
-import * as SignatureValidator from '../generated-artifacts/SignatureValidator.json';
+import * as SignatureValidatorFeature from '../generated-artifacts/SignatureValidatorFeature.json';
-import * as SimpleFunctionRegistry from '../generated-artifacts/SimpleFunctionRegistry.json';
+import * as SimpleFunctionRegistryFeature from '../generated-artifacts/SimpleFunctionRegistryFeature.json';
-import * as TokenSpender from '../generated-artifacts/TokenSpender.json';
+import * as TokenSpenderFeature from '../generated-artifacts/TokenSpenderFeature.json';
-import * as TransformERC20 from '../generated-artifacts/TransformERC20.json';
+import * as TransformERC20Feature from '../generated-artifacts/TransformERC20Feature.json';
 import * as WethTransformer from '../generated-artifacts/WethTransformer.json';
 import * as ZeroEx from '../generated-artifacts/ZeroEx.json';
 export const artifacts = {
@@ -35,19 +36,20 @@ export const artifacts = {
     IFlashWallet: IFlashWallet as ContractArtifact,
     IAllowanceTarget: IAllowanceTarget as ContractArtifact,
     IERC20Transformer: IERC20Transformer as ContractArtifact,
-    IOwnable: IOwnable as ContractArtifact,
+    IOwnableFeature: IOwnableFeature as ContractArtifact,
-    ISimpleFunctionRegistry: ISimpleFunctionRegistry as ContractArtifact,
+    ISimpleFunctionRegistryFeature: ISimpleFunctionRegistryFeature as ContractArtifact,
-    ITokenSpender: ITokenSpender as ContractArtifact,
+    ITokenSpenderFeature: ITokenSpenderFeature as ContractArtifact,
-    ITransformERC20: ITransformERC20 as ContractArtifact,
+    ITransformERC20Feature: ITransformERC20Feature as ContractArtifact,
     FillQuoteTransformer: FillQuoteTransformer as ContractArtifact,
     PayTakerTransformer: PayTakerTransformer as ContractArtifact,
     WethTransformer: WethTransformer as ContractArtifact,
-    Ownable: Ownable as ContractArtifact,
+    OwnableFeature: OwnableFeature as ContractArtifact,
-    SimpleFunctionRegistry: SimpleFunctionRegistry as ContractArtifact,
+    SimpleFunctionRegistryFeature: SimpleFunctionRegistryFeature as ContractArtifact,
-    TransformERC20: TransformERC20 as ContractArtifact,
+    TransformERC20Feature: TransformERC20Feature as ContractArtifact,
-    TokenSpender: TokenSpender as ContractArtifact,
+    TokenSpenderFeature: TokenSpenderFeature as ContractArtifact,
     AffiliateFeeTransformer: AffiliateFeeTransformer as ContractArtifact,
-    SignatureValidator: SignatureValidator as ContractArtifact,
+    SignatureValidatorFeature: SignatureValidatorFeature as ContractArtifact,
-    MetaTransactions: MetaTransactions as ContractArtifact,
+    MetaTransactionsFeature: MetaTransactionsFeature as ContractArtifact,
+    LogMetadataTransformer: LogMetadataTransformer as ContractArtifact,
     BridgeAdapter: BridgeAdapter as ContractArtifact,
 };

contracts/zero-ex/src/index.ts

@@ -36,13 +36,14 @@ export {
     AffiliateFeeTransformerContract,
     BridgeAdapterContract,
     FillQuoteTransformerContract,
-    IOwnableContract,
+    IOwnableFeatureContract,
-    IOwnableEvents,
+    IOwnableFeatureEvents,
-    ISimpleFunctionRegistryContract,
+    ISimpleFunctionRegistryFeatureContract,
-    ISimpleFunctionRegistryEvents,
+    ISimpleFunctionRegistryFeatureEvents,
-    ITokenSpenderContract,
+    ITokenSpenderFeatureContract,
-    ITransformERC20Contract,
+    ITransformERC20FeatureContract,
     IZeroExContract,
+    LogMetadataTransformerContract,
     PayTakerTransformerContract,
     WethTransformerContract,
     ZeroExContract,

contracts/zero-ex/src/migration.ts

@@ -6,12 +6,13 @@ import { artifacts } from './artifacts';
 import {
     FullMigrationContract,
     InitialMigrationContract,
-    MetaTransactionsContract,
+    IZeroExContract,
-    OwnableContract,
+    MetaTransactionsFeatureContract,
-    SignatureValidatorContract,
+    OwnableFeatureContract,
-    SimpleFunctionRegistryContract,
+    SignatureValidatorFeatureContract,
-    TokenSpenderContract,
+    SimpleFunctionRegistryFeatureContract,
-    TransformERC20Contract,
+    TokenSpenderFeatureContract,
+    TransformERC20FeatureContract,
     ZeroExContract,
 } from './wrappers';
 
@@ -36,16 +37,20 @@ export async function deployBootstrapFeaturesAsync(
     return {
         registry:
             features.registry ||
-            (await SimpleFunctionRegistryContract.deployFrom0xArtifactAsync(
+            (await SimpleFunctionRegistryFeatureContract.deployFrom0xArtifactAsync(
-                artifacts.SimpleFunctionRegistry,
+                artifacts.SimpleFunctionRegistryFeature,
                 provider,
                 txDefaults,
                 artifacts,
             )).address,
         ownable:
             features.ownable ||
-            (await OwnableContract.deployFrom0xArtifactAsync(artifacts.Ownable, provider, txDefaults, artifacts))
+            (await OwnableFeatureContract.deployFrom0xArtifactAsync(
-                .address,
+                artifacts.OwnableFeature,
+                provider,
+                txDefaults,
+                artifacts,
+            )).address,
     };
 }
 
@@ -107,32 +112,32 @@ export async function deployFullFeaturesAsync(
         ...(await deployBootstrapFeaturesAsync(provider, txDefaults)),
         tokenSpender:
             features.tokenSpender ||
-            (await TokenSpenderContract.deployFrom0xArtifactAsync(
+            (await TokenSpenderFeatureContract.deployFrom0xArtifactAsync(
-                artifacts.TokenSpender,
+                artifacts.TokenSpenderFeature,
                 provider,
                 txDefaults,
                 artifacts,
             )).address,
         transformERC20:
             features.transformERC20 ||
-            (await TransformERC20Contract.deployFrom0xArtifactAsync(
+            (await TransformERC20FeatureContract.deployFrom0xArtifactAsync(
-                artifacts.TransformERC20,
+                artifacts.TransformERC20Feature,
                 provider,
                 txDefaults,
                 artifacts,
             )).address,
         signatureValidator:
             features.signatureValidator ||
-            (await SignatureValidatorContract.deployFrom0xArtifactAsync(
+            (await SignatureValidatorFeatureContract.deployFrom0xArtifactAsync(
-                artifacts.SignatureValidator,
+                artifacts.SignatureValidatorFeature,
                 provider,
                 txDefaults,
                 artifacts,
             )).address,
         metaTransactions:
             features.metaTransactions ||
-            (await MetaTransactionsContract.deployFrom0xArtifactAsync(
+            (await MetaTransactionsFeatureContract.deployFrom0xArtifactAsync(
-                artifacts.MetaTransactions,
+                artifacts.MetaTransactionsFeature,
                 provider,
                 txDefaults,
                 artifacts,
@@ -150,7 +155,7 @@ export async function fullMigrateAsync(
     txDefaults: Partial<TxData>,
     features: Partial<FullFeatures> = {},
     opts: Partial<FullMigrationOpts> = {},
-): Promise<ZeroExContract> {
+): Promise<IZeroExContract> {
     const migrator = await FullMigrationContract.deployFrom0xArtifactAsync(
         artifacts.FullMigration,
         provider,
@@ -171,5 +176,5 @@ export async function fullMigrateAsync(
         ...opts,
     };
     await migrator.initializeZeroEx(owner, zeroEx.address, _features, _opts).awaitTransactionSuccessAsync();
-    return zeroEx;
+    return new IZeroExContract(zeroEx.address, provider, txDefaults);
 }

contracts/zero-ex/src/wrappers.ts

@@ -10,18 +10,19 @@ export * from '../generated-wrappers/full_migration';
 export * from '../generated-wrappers/i_allowance_target';
 export * from '../generated-wrappers/i_erc20_transformer';
 export * from '../generated-wrappers/i_flash_wallet';
-export * from '../generated-wrappers/i_ownable';
+export * from '../generated-wrappers/i_ownable_feature';
-export * from '../generated-wrappers/i_simple_function_registry';
+export * from '../generated-wrappers/i_simple_function_registry_feature';
-export * from '../generated-wrappers/i_token_spender';
+export * from '../generated-wrappers/i_token_spender_feature';
-export * from '../generated-wrappers/i_transform_erc20';
+export * from '../generated-wrappers/i_transform_erc20_feature';
 export * from '../generated-wrappers/i_zero_ex';
 export * from '../generated-wrappers/initial_migration';
-export * from '../generated-wrappers/meta_transactions';
+export * from '../generated-wrappers/log_metadata_transformer';
-export * from '../generated-wrappers/ownable';
+export * from '../generated-wrappers/meta_transactions_feature';
+export * from '../generated-wrappers/ownable_feature';
 export * from '../generated-wrappers/pay_taker_transformer';
-export * from '../generated-wrappers/signature_validator';
+export * from '../generated-wrappers/signature_validator_feature';
-export * from '../generated-wrappers/simple_function_registry';
+export * from '../generated-wrappers/simple_function_registry_feature';
-export * from '../generated-wrappers/token_spender';
+export * from '../generated-wrappers/token_spender_feature';
-export * from '../generated-wrappers/transform_erc20';
+export * from '../generated-wrappers/transform_erc20_feature';
 export * from '../generated-wrappers/weth_transformer';
 export * from '../generated-wrappers/zero_ex';

contracts/zero-ex/test/artifacts.ts

@@ -7,15 +7,16 @@ import { ContractArtifact } from 'ethereum-types';
 
 import * as AffiliateFeeTransformer from '../test/generated-artifacts/AffiliateFeeTransformer.json';
 import * as AllowanceTarget from '../test/generated-artifacts/AllowanceTarget.json';
-import * as Bootstrap from '../test/generated-artifacts/Bootstrap.json';
+import * as BootstrapFeature from '../test/generated-artifacts/BootstrapFeature.json';
 import * as BridgeAdapter from '../test/generated-artifacts/BridgeAdapter.json';
 import * as FillQuoteTransformer from '../test/generated-artifacts/FillQuoteTransformer.json';
 import * as FixinCommon from '../test/generated-artifacts/FixinCommon.json';
 import * as FixinEIP712 from '../test/generated-artifacts/FixinEIP712.json';
+import * as FixinReentrancyGuard from '../test/generated-artifacts/FixinReentrancyGuard.json';
 import * as FlashWallet from '../test/generated-artifacts/FlashWallet.json';
 import * as FullMigration from '../test/generated-artifacts/FullMigration.json';
 import * as IAllowanceTarget from '../test/generated-artifacts/IAllowanceTarget.json';
-import * as IBootstrap from '../test/generated-artifacts/IBootstrap.json';
+import * as IBootstrapFeature from '../test/generated-artifacts/IBootstrapFeature.json';
 import * as IBridgeAdapter from '../test/generated-artifacts/IBridgeAdapter.json';
 import * as IERC20Bridge from '../test/generated-artifacts/IERC20Bridge.json';
 import * as IERC20Transformer from '../test/generated-artifacts/IERC20Transformer.json';
@@ -23,14 +24,14 @@ import * as IExchange from '../test/generated-artifacts/IExchange.json';
 import * as IFeature from '../test/generated-artifacts/IFeature.json';
 import * as IFlashWallet from '../test/generated-artifacts/IFlashWallet.json';
 import * as IGasToken from '../test/generated-artifacts/IGasToken.json';
-import * as IMetaTransactions from '../test/generated-artifacts/IMetaTransactions.json';
+import * as IMetaTransactionsFeature from '../test/generated-artifacts/IMetaTransactionsFeature.json';
 import * as InitialMigration from '../test/generated-artifacts/InitialMigration.json';
-import * as IOwnable from '../test/generated-artifacts/IOwnable.json';
+import * as IOwnableFeature from '../test/generated-artifacts/IOwnableFeature.json';
-import * as ISignatureValidator from '../test/generated-artifacts/ISignatureValidator.json';
+import * as ISignatureValidatorFeature from '../test/generated-artifacts/ISignatureValidatorFeature.json';
-import * as ISimpleFunctionRegistry from '../test/generated-artifacts/ISimpleFunctionRegistry.json';
+import * as ISimpleFunctionRegistryFeature from '../test/generated-artifacts/ISimpleFunctionRegistryFeature.json';
 import * as ITestSimpleFunctionRegistryFeature from '../test/generated-artifacts/ITestSimpleFunctionRegistryFeature.json';
-import * as ITokenSpender from '../test/generated-artifacts/ITokenSpender.json';
+import * as ITokenSpenderFeature from '../test/generated-artifacts/ITokenSpenderFeature.json';
-import * as ITransformERC20 from '../test/generated-artifacts/ITransformERC20.json';
+import * as ITransformERC20Feature from '../test/generated-artifacts/ITransformERC20Feature.json';
 import * as IZeroEx from '../test/generated-artifacts/IZeroEx.json';
 import * as LibBootstrap from '../test/generated-artifacts/LibBootstrap.json';
 import * as LibCommonRichErrors from '../test/generated-artifacts/LibCommonRichErrors.json';
@@ -42,6 +43,7 @@ import * as LibOwnableRichErrors from '../test/generated-artifacts/LibOwnableRic
 import * as LibOwnableStorage from '../test/generated-artifacts/LibOwnableStorage.json';
 import * as LibProxyRichErrors from '../test/generated-artifacts/LibProxyRichErrors.json';
 import * as LibProxyStorage from '../test/generated-artifacts/LibProxyStorage.json';
+import * as LibReentrancyGuardStorage from '../test/generated-artifacts/LibReentrancyGuardStorage.json';
 import * as LibSignatureRichErrors from '../test/generated-artifacts/LibSignatureRichErrors.json';
 import * as LibSignedCallData from '../test/generated-artifacts/LibSignedCallData.json';
 import * as LibSimpleFunctionRegistryRichErrors from '../test/generated-artifacts/LibSimpleFunctionRegistryRichErrors.json';
@@ -52,20 +54,22 @@ import * as LibTokenSpenderStorage from '../test/generated-artifacts/LibTokenSpe
 import * as LibTransformERC20RichErrors from '../test/generated-artifacts/LibTransformERC20RichErrors.json';
 import * as LibTransformERC20Storage from '../test/generated-artifacts/LibTransformERC20Storage.json';
 import * as LibWalletRichErrors from '../test/generated-artifacts/LibWalletRichErrors.json';
-import * as MetaTransactions from '../test/generated-artifacts/MetaTransactions.json';
+import * as LogMetadataTransformer from '../test/generated-artifacts/LogMetadataTransformer.json';
+import * as MetaTransactionsFeature from '../test/generated-artifacts/MetaTransactionsFeature.json';
 import * as MixinAdapterAddresses from '../test/generated-artifacts/MixinAdapterAddresses.json';
 import * as MixinBalancer from '../test/generated-artifacts/MixinBalancer.json';
 import * as MixinCurve from '../test/generated-artifacts/MixinCurve.json';
 import * as MixinKyber from '../test/generated-artifacts/MixinKyber.json';
+import * as MixinMooniswap from '../test/generated-artifacts/MixinMooniswap.json';
 import * as MixinMStable from '../test/generated-artifacts/MixinMStable.json';
 import * as MixinOasis from '../test/generated-artifacts/MixinOasis.json';
 import * as MixinUniswap from '../test/generated-artifacts/MixinUniswap.json';
 import * as MixinUniswapV2 from '../test/generated-artifacts/MixinUniswapV2.json';
 import * as MixinZeroExBridge from '../test/generated-artifacts/MixinZeroExBridge.json';
-import * as Ownable from '../test/generated-artifacts/Ownable.json';
+import * as OwnableFeature from '../test/generated-artifacts/OwnableFeature.json';
 import * as PayTakerTransformer from '../test/generated-artifacts/PayTakerTransformer.json';
-import * as SignatureValidator from '../test/generated-artifacts/SignatureValidator.json';
+import * as SignatureValidatorFeature from '../test/generated-artifacts/SignatureValidatorFeature.json';
-import * as SimpleFunctionRegistry from '../test/generated-artifacts/SimpleFunctionRegistry.json';
+import * as SimpleFunctionRegistryFeature from '../test/generated-artifacts/SimpleFunctionRegistryFeature.json';
 import * as TestCallTarget from '../test/generated-artifacts/TestCallTarget.json';
 import * as TestDelegateCaller from '../test/generated-artifacts/TestDelegateCaller.json';
 import * as TestFillQuoteTransformerBridge from '../test/generated-artifacts/TestFillQuoteTransformerBridge.json';
@@ -88,26 +92,15 @@ import * as TestTransformerHost from '../test/generated-artifacts/TestTransforme
 import * as TestWeth from '../test/generated-artifacts/TestWeth.json';
 import * as TestWethTransformerHost from '../test/generated-artifacts/TestWethTransformerHost.json';
 import * as TestZeroExFeature from '../test/generated-artifacts/TestZeroExFeature.json';
-import * as TokenSpender from '../test/generated-artifacts/TokenSpender.json';
+import * as TokenSpenderFeature from '../test/generated-artifacts/TokenSpenderFeature.json';
 import * as Transformer from '../test/generated-artifacts/Transformer.json';
-import * as TransformERC20 from '../test/generated-artifacts/TransformERC20.json';
+import * as TransformERC20Feature from '../test/generated-artifacts/TransformERC20Feature.json';
 import * as TransformerDeployer from '../test/generated-artifacts/TransformerDeployer.json';
 import * as WethTransformer from '../test/generated-artifacts/WethTransformer.json';
 import * as ZeroEx from '../test/generated-artifacts/ZeroEx.json';
 export const artifacts = {
     IZeroEx: IZeroEx as ContractArtifact,
     ZeroEx: ZeroEx as ContractArtifact,
-    BridgeAdapter: BridgeAdapter as ContractArtifact,
-    IBridgeAdapter: IBridgeAdapter as ContractArtifact,
-    MixinAdapterAddresses: MixinAdapterAddresses as ContractArtifact,
-    MixinBalancer: MixinBalancer as ContractArtifact,
-    MixinCurve: MixinCurve as ContractArtifact,
-    MixinKyber: MixinKyber as ContractArtifact,
-    MixinMStable: MixinMStable as ContractArtifact,
-    MixinOasis: MixinOasis as ContractArtifact,
-    MixinUniswap: MixinUniswap as ContractArtifact,
-    MixinUniswapV2: MixinUniswapV2 as ContractArtifact,
-    MixinZeroExBridge: MixinZeroExBridge as ContractArtifact,
     LibCommonRichErrors: LibCommonRichErrors as ContractArtifact,
     LibMetaTransactionsRichErrors: LibMetaTransactionsRichErrors as ContractArtifact,
     LibOwnableRichErrors: LibOwnableRichErrors as ContractArtifact,
@@ -122,24 +115,25 @@ export const artifacts = {
     IAllowanceTarget: IAllowanceTarget as ContractArtifact,
     IFlashWallet: IFlashWallet as ContractArtifact,
     TransformerDeployer: TransformerDeployer as ContractArtifact,
-    Bootstrap: Bootstrap as ContractArtifact,
+    BootstrapFeature: BootstrapFeature as ContractArtifact,
-    IBootstrap: IBootstrap as ContractArtifact,
+    IBootstrapFeature: IBootstrapFeature as ContractArtifact,
     IFeature: IFeature as ContractArtifact,
-    IMetaTransactions: IMetaTransactions as ContractArtifact,
+    IMetaTransactionsFeature: IMetaTransactionsFeature as ContractArtifact,
-    IOwnable: IOwnable as ContractArtifact,
+    IOwnableFeature: IOwnableFeature as ContractArtifact,
-    ISignatureValidator: ISignatureValidator as ContractArtifact,
+    ISignatureValidatorFeature: ISignatureValidatorFeature as ContractArtifact,
-    ISimpleFunctionRegistry: ISimpleFunctionRegistry as ContractArtifact,
+    ISimpleFunctionRegistryFeature: ISimpleFunctionRegistryFeature as ContractArtifact,
-    ITokenSpender: ITokenSpender as ContractArtifact,
+    ITokenSpenderFeature: ITokenSpenderFeature as ContractArtifact,
-    ITransformERC20: ITransformERC20 as ContractArtifact,
+    ITransformERC20Feature: ITransformERC20Feature as ContractArtifact,
-    MetaTransactions: MetaTransactions as ContractArtifact,
+    MetaTransactionsFeature: MetaTransactionsFeature as ContractArtifact,
-    Ownable: Ownable as ContractArtifact,
+    OwnableFeature: OwnableFeature as ContractArtifact,
-    SignatureValidator: SignatureValidator as ContractArtifact,
+    SignatureValidatorFeature: SignatureValidatorFeature as ContractArtifact,
-    SimpleFunctionRegistry: SimpleFunctionRegistry as ContractArtifact,
+    SimpleFunctionRegistryFeature: SimpleFunctionRegistryFeature as ContractArtifact,
-    TokenSpender: TokenSpender as ContractArtifact,
+    TokenSpenderFeature: TokenSpenderFeature as ContractArtifact,
-    TransformERC20: TransformERC20 as ContractArtifact,
+    TransformERC20Feature: TransformERC20Feature as ContractArtifact,
     LibSignedCallData: LibSignedCallData as ContractArtifact,
     FixinCommon: FixinCommon as ContractArtifact,
     FixinEIP712: FixinEIP712 as ContractArtifact,
+    FixinReentrancyGuard: FixinReentrancyGuard as ContractArtifact,
     FullMigration: FullMigration as ContractArtifact,
     InitialMigration: InitialMigration as ContractArtifact,
     LibBootstrap: LibBootstrap as ContractArtifact,
@@ -147,6 +141,7 @@ export const artifacts = {
     LibMetaTransactionsStorage: LibMetaTransactionsStorage as ContractArtifact,
     LibOwnableStorage: LibOwnableStorage as ContractArtifact,
     LibProxyStorage: LibProxyStorage as ContractArtifact,
+    LibReentrancyGuardStorage: LibReentrancyGuardStorage as ContractArtifact,
     LibSimpleFunctionRegistryStorage: LibSimpleFunctionRegistryStorage as ContractArtifact,
     LibStorage: LibStorage as ContractArtifact,
     LibTokenSpenderStorage: LibTokenSpenderStorage as ContractArtifact,
@@ -155,9 +150,22 @@ export const artifacts = {
     FillQuoteTransformer: FillQuoteTransformer as ContractArtifact,
     IERC20Transformer: IERC20Transformer as ContractArtifact,
     LibERC20Transformer: LibERC20Transformer as ContractArtifact,
+    LogMetadataTransformer: LogMetadataTransformer as ContractArtifact,
     PayTakerTransformer: PayTakerTransformer as ContractArtifact,
     Transformer: Transformer as ContractArtifact,
     WethTransformer: WethTransformer as ContractArtifact,
+    BridgeAdapter: BridgeAdapter as ContractArtifact,
+    IBridgeAdapter: IBridgeAdapter as ContractArtifact,
+    MixinAdapterAddresses: MixinAdapterAddresses as ContractArtifact,
+    MixinBalancer: MixinBalancer as ContractArtifact,
+    MixinCurve: MixinCurve as ContractArtifact,
+    MixinKyber: MixinKyber as ContractArtifact,
+    MixinMStable: MixinMStable as ContractArtifact,
+    MixinMooniswap: MixinMooniswap as ContractArtifact,
+    MixinOasis: MixinOasis as ContractArtifact,
+    MixinUniswap: MixinUniswap as ContractArtifact,
+    MixinUniswapV2: MixinUniswapV2 as ContractArtifact,
+    MixinZeroExBridge: MixinZeroExBridge as ContractArtifact,
     IERC20Bridge: IERC20Bridge as ContractArtifact,
     IExchange: IExchange as ContractArtifact,
     IGasToken: IGasToken as ContractArtifact,

contracts/zero-ex/test/features/meta_transactions_test.ts

@@ -12,12 +12,12 @@ import { BigNumber, hexUtils, StringRevertError, ZeroExRevertErrors } from '@0x/
 import * as _ from 'lodash';
 
 import { generateCallDataSignature, signCallData } from '../../src/signed_call_data';
-import { MetaTransactionsContract, ZeroExContract } from '../../src/wrappers';
+import { IZeroExContract, MetaTransactionsFeatureContract } from '../../src/wrappers';
 import { artifacts } from '../artifacts';
 import { abis } from '../utils/abis';
 import { fullMigrateAsync } from '../utils/migration';
 import {
-    ITokenSpenderContract,
+    ITokenSpenderFeatureContract,
     TestMetaTransactionsTransformERC20FeatureContract,
     TestMetaTransactionsTransformERC20FeatureEvents,
     TestMintableERC20TokenContract,
@@ -29,13 +29,17 @@ blockchainTests.resets('MetaTransactions feature', env => {
     let owner: string;
     let sender: string;
     let signers: string[];
-    let zeroEx: ZeroExContract;
+    let zeroEx: IZeroExContract;
-    let feature: MetaTransactionsContract;
+    let feature: MetaTransactionsFeatureContract;
     let feeToken: TestMintableERC20TokenContract;
     let transformERC20Feature: TestMetaTransactionsTransformERC20FeatureContract;
     let allowanceTarget: string;
 
     const MAX_FEE_AMOUNT = new BigNumber('1e18');
+    const TRANSFORM_ERC20_FAILING_VALUE = new BigNumber(666);
+    const TRANSFORM_ERC20_REENTER_VALUE = new BigNumber(777);
+    const TRANSFORM_ERC20_BATCH_REENTER_VALUE = new BigNumber(888);
+    const REENTRANCY_FLAG_MTX = 0x1;
 
     before(async () => {
         [owner, sender, ...signers] = await env.getAccountAddressesAsync();
@@ -48,14 +52,19 @@ blockchainTests.resets('MetaTransactions feature', env => {
         zeroEx = await fullMigrateAsync(owner, env.provider, env.txDefaults, {
             transformERC20: transformERC20Feature.address,
         });
-        feature = new MetaTransactionsContract(zeroEx.address, env.provider, { ...env.txDefaults, from: sender }, abis);
+        feature = new MetaTransactionsFeatureContract(
+            zeroEx.address,
+            env.provider,
+            { ...env.txDefaults, from: sender },
+            abis,
+        );
         feeToken = await TestMintableERC20TokenContract.deployFrom0xArtifactAsync(
             artifacts.TestMintableERC20Token,
             env.provider,
             env.txDefaults,
             {},
         );
-        allowanceTarget = await new ITokenSpenderContract(zeroEx.address, env.provider, env.txDefaults)
+        allowanceTarget = await new ITokenSpenderFeatureContract(zeroEx.address, env.provider, env.txDefaults)
             .getAllowanceTarget()
             .callAsync();
         // Fund signers with fee tokens.
@@ -263,7 +272,7 @@ blockchainTests.resets('MetaTransactions feature', env => {
         it('fails if the translated call fails', async () => {
             const args = getRandomTransformERC20Args();
             const mtx = getRandomMetaTransaction({
-                value: new BigNumber(666),
+                value: new BigNumber(TRANSFORM_ERC20_FAILING_VALUE),
                 callData: transformERC20Feature
                     .transformERC20(
                         args.inputToken,
@@ -297,7 +306,7 @@ blockchainTests.resets('MetaTransactions feature', env => {
                 new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
                     mtxHash,
                     actualCallData,
-                    new StringRevertError('FAIL').toString(),
+                    new StringRevertError('FAIL').encode(),
                 ),
             );
         });
@@ -465,7 +474,139 @@ blockchainTests.resets('MetaTransactions feature', env => {
                         mtxHash,
                         signers[0],
                         signature,
-                    ).toString(),
+                    ).encode(),
+                ),
+            );
+        });
+
+        it('cannot reenter `executeMetaTransaction()`', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+                value: TRANSFORM_ERC20_REENTER_VALUE,
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.maxGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.executeMetaTransaction(mtx, signature).awaitTransactionSuccessAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new ZeroExRevertErrors.Common.IllegalReentrancyError(
+                        feature.getSelector('executeMetaTransaction'),
+                        REENTRANCY_FLAG_MTX,
+                    ).encode(),
+                ),
+            );
+        });
+
+        it('cannot reenter `batchExecuteMetaTransactions()`', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+                value: TRANSFORM_ERC20_BATCH_REENTER_VALUE,
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.maxGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.executeMetaTransaction(mtx, signature).awaitTransactionSuccessAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new ZeroExRevertErrors.Common.IllegalReentrancyError(
+                        feature.getSelector('batchExecuteMetaTransactions'),
+                        REENTRANCY_FLAG_MTX,
+                    ).encode(),
+                ),
+            );
+        });
+
+        it('cannot reenter `executeMetaTransaction()`', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+                value: TRANSFORM_ERC20_REENTER_VALUE,
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.maxGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.executeMetaTransaction(mtx, signature).awaitTransactionSuccessAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new ZeroExRevertErrors.Common.IllegalReentrancyError(
+                        feature.getSelector('executeMetaTransaction'),
+                        REENTRANCY_FLAG_MTX,
+                    ).encode(),
+                ),
+            );
+        });
+
+        it('cannot reenter `batchExecuteMetaTransactions()`', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+                value: TRANSFORM_ERC20_BATCH_REENTER_VALUE,
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.maxGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.executeMetaTransaction(mtx, signature).awaitTransactionSuccessAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new ZeroExRevertErrors.Common.IllegalReentrancyError(
+                        feature.getSelector('batchExecuteMetaTransactions'),
+                        REENTRANCY_FLAG_MTX,
+                    ).encode(),
                 ),
             );
         });
@@ -526,6 +667,102 @@ blockchainTests.resets('MetaTransactions feature', env => {
                 new ZeroExRevertErrors.MetaTransactions.MetaTransactionAlreadyExecutedError(mtxHash, block),
             );
         });
+
+        it('fails if a meta-transaction fails', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                value: new BigNumber(TRANSFORM_ERC20_FAILING_VALUE),
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.minGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.batchExecuteMetaTransactions([mtx], [signature]).callAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new StringRevertError('FAIL').encode(),
+                ),
+            );
+        });
+
+        it('cannot reenter `executeMetaTransaction()`', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+                value: TRANSFORM_ERC20_REENTER_VALUE,
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.maxGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.batchExecuteMetaTransactions([mtx], [signature]).awaitTransactionSuccessAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new ZeroExRevertErrors.Common.IllegalReentrancyError(
+                        feature.getSelector('executeMetaTransaction'),
+                        REENTRANCY_FLAG_MTX,
+                    ).encode(),
+                ),
+            );
+        });
+
+        it('cannot reenter `batchExecuteMetaTransactions()`', async () => {
+            const args = getRandomTransformERC20Args();
+            const mtx = getRandomMetaTransaction({
+                callData: transformERC20Feature
+                    .transformERC20(
+                        args.inputToken,
+                        args.outputToken,
+                        args.inputTokenAmount,
+                        args.minOutputTokenAmount,
+                        args.transformations,
+                    )
+                    .getABIEncodedTransactionData(),
+                value: TRANSFORM_ERC20_BATCH_REENTER_VALUE,
+            });
+            const mtxHash = getExchangeProxyMetaTransactionHash(mtx);
+            const signature = await signMetaTransactionAsync(mtx);
+            const callOpts = {
+                gasPrice: mtx.maxGasPrice,
+                value: mtx.value,
+            };
+            const tx = feature.batchExecuteMetaTransactions([mtx], [signature]).awaitTransactionSuccessAsync(callOpts);
+            return expect(tx).to.revertWith(
+                new ZeroExRevertErrors.MetaTransactions.MetaTransactionCallFailedError(
+                    mtxHash,
+                    undefined,
+                    new ZeroExRevertErrors.Common.IllegalReentrancyError(
+                        feature.getSelector('batchExecuteMetaTransactions'),
+                        REENTRANCY_FLAG_MTX,
+                    ).encode(),
+                ),
+            );
+        });
     });
 
     describe('getMetaTransactionExecutedBlock()', () => {

contracts/zero-ex/test/features/ownable_test.ts

@@ -3,12 +3,12 @@ import { hexUtils, OwnableRevertErrors, StringRevertError, ZeroExRevertErrors }
 
 import { artifacts } from '../artifacts';
 import { initialMigrateAsync } from '../utils/migration';
-import { IOwnableContract, IOwnableEvents, TestMigratorContract, TestMigratorEvents } from '../wrappers';
+import { IOwnableFeatureContract, IOwnableFeatureEvents, TestMigratorContract, TestMigratorEvents } from '../wrappers';
 
 blockchainTests.resets('Ownable feature', env => {
     const notOwner = randomAddress();
     let owner: string;
-    let ownable: IOwnableContract;
+    let ownable: IOwnableFeatureContract;
     let testMigrator: TestMigratorContract;
     let succeedingMigrateFnCallData: string;
     let failingMigrateFnCallData: string;
@@ -19,7 +19,7 @@ blockchainTests.resets('Ownable feature', env => {
         [owner] = await env.getAccountAddressesAsync();
         logDecoder = new LogDecoder(env.web3Wrapper, artifacts);
         const zeroEx = await initialMigrateAsync(owner, env.provider, env.txDefaults);
-        ownable = new IOwnableContract(zeroEx.address, env.provider, env.txDefaults);
+        ownable = new IOwnableFeatureContract(zeroEx.address, env.provider, env.txDefaults);
         testMigrator = await TestMigratorContract.deployFrom0xArtifactAsync(
             artifacts.TestMigrator,
             env.provider,
@@ -49,7 +49,7 @@ blockchainTests.resets('Ownable feature', env => {
                         newOwner,
                     },
                 ],
-                IOwnableEvents.OwnershipTransferred,
+                IOwnableFeatureEvents.OwnershipTransferred,
             );
             expect(await ownable.owner().callAsync()).to.eq(newOwner);
         });
@@ -102,7 +102,7 @@ blockchainTests.resets('Ownable feature', env => {
             return expect(tx).to.revertWith(
                 new ZeroExRevertErrors.Ownable.MigrateCallFailedError(
                     testMigrator.address,
-                    new StringRevertError('OOPSIE').toString(),
+                    new StringRevertError('OOPSIE').encode(),
                 ),
             );
         });

contracts/zero-ex/test/features/signature_validator_test.ts

@@ -5,7 +5,7 @@ import { hexUtils, ZeroExRevertErrors } from '@0x/utils';
 import * as ethjs from 'ethereumjs-util';
 import * as _ from 'lodash';
 
-import { SignatureValidatorContract, ZeroExContract } from '../../src/wrappers';
+import { IZeroExContract, SignatureValidatorFeatureContract } from '../../src/wrappers';
 import { abis } from '../utils/abis';
 import { fullMigrateAsync } from '../utils/migration';
 
@@ -14,13 +14,13 @@ const { NULL_BYTES } = constants;
 blockchainTests.resets('SignatureValidator feature', env => {
     let owner: string;
     let signers: string[];
-    let zeroEx: ZeroExContract;
+    let zeroEx: IZeroExContract;
-    let feature: SignatureValidatorContract;
+    let feature: SignatureValidatorFeatureContract;
 
     before(async () => {
         [owner, ...signers] = await env.getAccountAddressesAsync();
         zeroEx = await fullMigrateAsync(owner, env.provider, env.txDefaults);
-        feature = new SignatureValidatorContract(zeroEx.address, env.provider, env.txDefaults, abis);
+        feature = new SignatureValidatorFeatureContract(zeroEx.address, env.provider, env.txDefaults, abis);
     });
 
     describe('validateHashSignature()', () => {

contracts/zero-ex/test/features/simple_function_registry_test.ts

@@ -5,8 +5,8 @@ import { ZeroExContract } from '../../src/wrappers';
 import { artifacts } from '../artifacts';
 import { initialMigrateAsync } from '../utils/migration';
 import {
-    ISimpleFunctionRegistryContract,
+    ISimpleFunctionRegistryFeatureContract,
-    ISimpleFunctionRegistryEvents,
+    ISimpleFunctionRegistryFeatureEvents,
     ITestSimpleFunctionRegistryFeatureContract,
     TestSimpleFunctionRegistryFeatureImpl1Contract,
     TestSimpleFunctionRegistryFeatureImpl2Contract,
@@ -17,7 +17,7 @@ blockchainTests.resets('SimpleFunctionRegistry feature', env => {
     const notOwner = randomAddress();
     let owner: string;
     let zeroEx: ZeroExContract;
-    let registry: ISimpleFunctionRegistryContract;
+    let registry: ISimpleFunctionRegistryFeatureContract;
     let testFnSelector: string;
     let testFeature: ITestSimpleFunctionRegistryFeatureContract;
     let testFeatureImpl1: TestSimpleFunctionRegistryFeatureImpl1Contract;
@@ -26,7 +26,7 @@ blockchainTests.resets('SimpleFunctionRegistry feature', env => {
     before(async () => {
         [owner] = await env.getAccountAddressesAsync();
         zeroEx = await initialMigrateAsync(owner, env.provider, env.txDefaults);
-        registry = new ISimpleFunctionRegistryContract(zeroEx.address, env.provider, {
+        registry = new ISimpleFunctionRegistryFeatureContract(zeroEx.address, env.provider, {
             ...env.txDefaults,
             from: owner,
         });
@@ -75,7 +75,7 @@ blockchainTests.resets('SimpleFunctionRegistry feature', env => {
         verifyEventsFromLogs(
             logs,
             [{ selector: testFnSelector, oldImpl: NULL_ADDRESS, newImpl: testFeatureImpl1.address }],
-            ISimpleFunctionRegistryEvents.ProxyFunctionUpdated,
+            ISimpleFunctionRegistryFeatureEvents.ProxyFunctionUpdated,
         );
         const r = await testFeature.testFn().callAsync();
         expect(r).to.bignumber.eq(1337);
@@ -117,7 +117,7 @@ blockchainTests.resets('SimpleFunctionRegistry feature', env => {
         verifyEventsFromLogs(
             logs,
             [{ selector: testFnSelector, oldImpl: testFeatureImpl2.address, newImpl: NULL_ADDRESS }],
-            ISimpleFunctionRegistryEvents.ProxyFunctionUpdated,
+            ISimpleFunctionRegistryFeatureEvents.ProxyFunctionUpdated,
         );
         const rollbackLength = await registry.getRollbackLength(testFnSelector).callAsync();
         expect(rollbackLength).to.bignumber.eq(0);

contracts/zero-ex/test/features/token_spender_test.ts

@@ -7,29 +7,29 @@ import {
 } from '@0x/contracts-test-utils';
 import { BigNumber, hexUtils, StringRevertError, ZeroExRevertErrors } from '@0x/utils';
 
-import { TokenSpenderContract, ZeroExContract } from '../../src/wrappers';
+import { IZeroExContract, TokenSpenderFeatureContract } from '../../src/wrappers';
 import { artifacts } from '../artifacts';
 import { abis } from '../utils/abis';
 import { fullMigrateAsync } from '../utils/migration';
 import { TestTokenSpenderERC20TokenContract, TestTokenSpenderERC20TokenEvents } from '../wrappers';
 
 blockchainTests.resets('TokenSpender feature', env => {
-    let zeroEx: ZeroExContract;
+    let zeroEx: IZeroExContract;
-    let feature: TokenSpenderContract;
+    let feature: TokenSpenderFeatureContract;
     let token: TestTokenSpenderERC20TokenContract;
     let allowanceTarget: string;
 
     before(async () => {
         const [owner] = await env.getAccountAddressesAsync();
         zeroEx = await fullMigrateAsync(owner, env.provider, env.txDefaults, {
-            tokenSpender: (await TokenSpenderContract.deployFrom0xArtifactAsync(
+            tokenSpender: (await TokenSpenderFeatureContract.deployFrom0xArtifactAsync(
                 artifacts.TestTokenSpender,
                 env.provider,
                 env.txDefaults,
                 artifacts,
             )).address,
         });
-        feature = new TokenSpenderContract(zeroEx.address, env.provider, env.txDefaults, abis);
+        feature = new TokenSpenderFeatureContract(zeroEx.address, env.provider, env.txDefaults, abis);
         token = await TestTokenSpenderERC20TokenContract.deployFrom0xArtifactAsync(
             artifacts.TestTokenSpenderERC20Token,
             env.provider,
@@ -98,7 +98,7 @@ blockchainTests.resets('TokenSpender feature', env => {
                 tokenFrom,
                 tokenTo,
                 tokenAmount,
-                new StringRevertError('TestTokenSpenderERC20Token/Revert').toString(),
+                new StringRevertError('TestTokenSpenderERC20Token/Revert').encode(),
             );
             return expect(tx).to.revertWith(expectedError);
         });

contracts/zero-ex/test/features/transform_erc20_test.ts

@@ -14,21 +14,21 @@ import { DecodedLogEntry } from 'ethereum-types';
 import * as ethjs from 'ethereumjs-util';
 
 import { generateCallDataHashSignature, signCallData } from '../../src/signed_call_data';
-import { TransformERC20Contract, ZeroExContract } from '../../src/wrappers';
+import { IZeroExContract, TransformERC20FeatureContract } from '../../src/wrappers';
 import { artifacts } from '../artifacts';
 import { abis } from '../utils/abis';
 import { fullMigrateAsync } from '../utils/migration';
 import {
     FlashWalletContract,
-    ITokenSpenderContract,
+    ITokenSpenderFeatureContract,
     TestMintableERC20TokenContract,
     TestMintTokenERC20TransformerContract,
     TestMintTokenERC20TransformerEvents,
     TestMintTokenERC20TransformerMintTransformEventArgs,
-    TransformERC20Events,
+    TransformERC20FeatureEvents,
 } from '../wrappers';
 
-const { NULL_BYTES, NULL_BYTES32 } = constants;
+const { NULL_ADDRESS, NULL_BYTES, NULL_BYTES32 } = constants;
 
 type MintTokenTransformerEvent = DecodedLogEntry<TestMintTokenERC20TransformerMintTransformEventArgs>;
 
@@ -37,20 +37,21 @@ blockchainTests.resets('TransformERC20 feature', env => {
     const callDataSigner = ethjs.bufferToHex(ethjs.privateToAddress(ethjs.toBuffer(callDataSignerKey)));
     let owner: string;
     let taker: string;
+    let sender: string;
     let transformerDeployer: string;
-    let zeroEx: ZeroExContract;
+    let zeroEx: IZeroExContract;
-    let feature: TransformERC20Contract;
+    let feature: TransformERC20FeatureContract;
     let wallet: FlashWalletContract;
     let allowanceTarget: string;
 
     before(async () => {
-        [owner, taker, transformerDeployer] = await env.getAccountAddressesAsync();
+        [owner, taker, sender, transformerDeployer] = await env.getAccountAddressesAsync();
         zeroEx = await fullMigrateAsync(
             owner,
             env.provider,
             env.txDefaults,
             {
-                transformERC20: (await TransformERC20Contract.deployFrom0xArtifactAsync(
+                transformERC20: (await TransformERC20FeatureContract.deployFrom0xArtifactAsync(
                     artifacts.TestTransformERC20,
                     env.provider,
                     env.txDefaults,
@@ -59,12 +60,17 @@ blockchainTests.resets('TransformERC20 feature', env => {
             },
             { transformerDeployer },
         );
-        feature = new TransformERC20Contract(zeroEx.address, env.provider, env.txDefaults, abis);
+        feature = new TransformERC20FeatureContract(
+            zeroEx.address,
+            env.provider,
+            { ...env.txDefaults, from: sender },
+            abis,
+        );
         wallet = new FlashWalletContract(await feature.getTransformWallet().callAsync(), env.provider, env.txDefaults);
-        allowanceTarget = await new ITokenSpenderContract(zeroEx.address, env.provider, env.txDefaults)
+        allowanceTarget = await new ITokenSpenderFeatureContract(zeroEx.address, env.provider, env.txDefaults)
             .getAllowanceTarget()
             .callAsync();
-        await feature.setQuoteSigner(callDataSigner).awaitTransactionSuccessAsync();
+        await feature.setQuoteSigner(callDataSigner).awaitTransactionSuccessAsync({ from: owner });
     });
 
     const { MAX_UINT256, ZERO_AMOUNT } = constants;
@@ -73,7 +79,7 @@ blockchainTests.resets('TransformERC20 feature', env => {
         it('createTransformWallet() replaces the current wallet', async () => {
             const newWalletAddress = await feature.createTransformWallet().callAsync({ from: owner });
             expect(newWalletAddress).to.not.eq(wallet.address);
-            await feature.createTransformWallet().awaitTransactionSuccessAsync();
+            await feature.createTransformWallet().awaitTransactionSuccessAsync({ from: owner });
             return expect(feature.getTransformWallet().callAsync()).to.eventually.eq(newWalletAddress);
         });
 
@@ -98,7 +104,7 @@ blockchainTests.resets('TransformERC20 feature', env => {
             verifyEventsFromLogs(
                 receipt.logs,
                 [{ transformerDeployer: newDeployer }],
-                TransformERC20Events.TransformerDeployerUpdated,
+                TransformERC20FeatureEvents.TransformerDeployerUpdated,
             );
             const actualDeployer = await feature.getTransformerDeployer().callAsync();
             expect(actualDeployer).to.eq(newDeployer);
@@ -121,7 +127,11 @@ blockchainTests.resets('TransformERC20 feature', env => {
         it('owner can set the quote signer with `setQuoteSigner()`', async () => {
             const newSigner = randomAddress();
             const receipt = await feature.setQuoteSigner(newSigner).awaitTransactionSuccessAsync({ from: owner });
-            verifyEventsFromLogs(receipt.logs, [{ quoteSigner: newSigner }], TransformERC20Events.QuoteSignerUpdated);
+            verifyEventsFromLogs(
+                receipt.logs,
+                [{ quoteSigner: newSigner }],
+                TransformERC20FeatureEvents.QuoteSignerUpdated,
+            );
             const actualSigner = await feature.getQuoteSigner().callAsync();
             expect(actualSigner).to.eq(newSigner);
         });
@@ -258,14 +268,15 @@ blockchainTests.resets('TransformERC20 feature', env => {
                             outputToken: outputToken.address,
                         },
                     ],
-                    TransformERC20Events.TransformedERC20,
+                    TransformERC20FeatureEvents.TransformedERC20,
                 );
                 verifyEventsFromLogs(
                     receipt.logs,
                     [
                         {
-                            callDataHash: NULL_BYTES32,
+                            sender,
                             taker,
+                            callDataHash: NULL_BYTES32,
                             context: wallet.address,
                             caller: zeroEx.address,
                             data: transformation.data,
@@ -314,14 +325,15 @@ blockchainTests.resets('TransformERC20 feature', env => {
                             outputToken: ETH_TOKEN_ADDRESS,
                         },
                     ],
-                    TransformERC20Events.TransformedERC20,
+                    TransformERC20FeatureEvents.TransformedERC20,
                 );
                 verifyEventsFromLogs(
                     receipt.logs,
                     [
                         {
-                            callDataHash: NULL_BYTES32,
                             taker,
+                            sender,
+                            callDataHash: NULL_BYTES32,
                             context: wallet.address,
                             caller: zeroEx.address,
                             data: transformation.data,
@@ -373,14 +385,15 @@ blockchainTests.resets('TransformERC20 feature', env => {
                             outputToken: outputToken.address,
                         },
                     ],
-                    TransformERC20Events.TransformedERC20,
+                    TransformERC20FeatureEvents.TransformedERC20,
                 );
                 verifyEventsFromLogs(
                     receipt.logs,
                     [
                         {
-                            callDataHash: NULL_BYTES32,
+                            sender,
                             taker,
+                            callDataHash: NULL_BYTES32,
                             context: wallet.address,
                             caller: zeroEx.address,
                             data: transformation.data,
@@ -496,8 +509,9 @@ blockchainTests.resets('TransformERC20 feature', env => {
                     receipt.logs,
                     [
                         {
-                            callDataHash: NULL_BYTES32,
+                            sender,
                             taker,
+                            callDataHash: NULL_BYTES32,
                             context: wallet.address,
                             caller: zeroEx.address,
                             data: transformations[0].data,
@@ -505,8 +519,9 @@ blockchainTests.resets('TransformERC20 feature', env => {
                             ethBalance: callValue,
                         },
                         {
-                            callDataHash: NULL_BYTES32,
+                            sender,
                             taker,
+                            callDataHash: NULL_BYTES32,
                             context: wallet.address,
                             caller: zeroEx.address,
                             data: transformations[1].data,
@@ -672,6 +687,37 @@ blockchainTests.resets('TransformERC20 feature', env => {
                 expect(actualCallDataHash).to.eq(hexUtils.hash(callData));
             });
 
+            it('passes the calldata hash to transformer when no quote signer configured', async () => {
+                const startingOutputTokenBalance = getRandomInteger(0, '100e18');
+                const startingInputTokenBalance = getRandomInteger(0, '100e18');
+                await outputToken.mint(taker, startingOutputTokenBalance).awaitTransactionSuccessAsync();
+                await inputToken.mint(taker, startingInputTokenBalance).awaitTransactionSuccessAsync();
+                const inputTokenAmount = getRandomPortion(startingInputTokenBalance);
+                const minOutputTokenAmount = getRandomInteger(1, '1e18');
+                const outputTokenMintAmount = minOutputTokenAmount;
+                const callValue = getRandomInteger(1, '1e18');
+                const transformation = createMintTokenTransformation({
+                    outputTokenMintAmount,
+                    inputTokenBurnAmunt: inputTokenAmount,
+                });
+                const bakedCall = feature.transformERC20(
+                    inputToken.address,
+                    outputToken.address,
+                    inputTokenAmount,
+                    minOutputTokenAmount,
+                    [transformation],
+                );
+                const callData = bakedCall.getABIEncodedTransactionData();
+                await feature.setQuoteSigner(NULL_ADDRESS).awaitTransactionSuccessAsync({ from: owner });
+                const receipt = await bakedCall.awaitTransactionSuccessAsync({
+                    from: taker,
+                    value: callValue,
+                    data: callData,
+                });
+                const { callDataHash: actualCallDataHash } = (receipt.logs[0] as MintTokenTransformerEvent).args;
+                expect(actualCallDataHash).to.eq(hexUtils.hash(callData));
+            });
+
             it('passes empty calldata hash to transformer with improperly signed calldata', async () => {
                 const startingOutputTokenBalance = getRandomInteger(0, '100e18');
                 const startingInputTokenBalance = getRandomInteger(0, '100e18');

contracts/zero-ex/test/flash_wallet_test.ts

@@ -127,7 +127,7 @@ blockchainTests.resets('FlashWallet', env => {
                     callTarget.address,
                     REVERTING_DATA,
                     constants.ZERO_AMOUNT,
-                    new StringRevertError('TestCallTarget/REVERT').toString(),
+                    new StringRevertError('TestCallTarget/REVERT'),
                 ),
             );
         });
@@ -203,7 +203,7 @@ blockchainTests.resets('FlashWallet', env => {
                     wallet.address,
                     callTarget.address,
                     REVERTING_DATA,
-                    new StringRevertError('TestCallTarget/REVERT').toString(),
+                    new StringRevertError('TestCallTarget/REVERT'),
                 ),
             );
         });

contracts/zero-ex/test/full_migration_test.ts

@@ -9,11 +9,11 @@ import { abis } from './utils/abis';
 import { deployFullFeaturesAsync, FullFeatures } from './utils/migration';
 import {
     AllowanceTargetContract,
-    IMetaTransactionsContract,
+    IMetaTransactionsFeatureContract,
-    IOwnableContract,
+    IOwnableFeatureContract,
-    ISignatureValidatorContract,
+    ISignatureValidatorFeatureContract,
-    ITokenSpenderContract,
+    ITokenSpenderFeatureContract,
-    ITransformERC20Contract,
+    ITransformERC20FeatureContract,
     TestFullMigrationContract,
     ZeroExContract,
 } from './wrappers';
@@ -50,7 +50,7 @@ blockchainTests.resets('Full migration', env => {
     });
 
     it('ZeroEx has the correct owner', async () => {
-        const ownable = new IOwnableContract(zeroEx.address, env.provider, env.txDefaults);
+        const ownable = new IOwnableFeatureContract(zeroEx.address, env.provider, env.txDefaults);
         const actualOwner = await ownable.owner().callAsync();
         expect(actualOwner).to.eq(owner);
     });
@@ -70,11 +70,11 @@ blockchainTests.resets('Full migration', env => {
 
     const FEATURE_FNS = {
         TokenSpender: {
-            contractType: ITokenSpenderContract,
+            contractType: ITokenSpenderFeatureContract,
             fns: ['_spendERC20Tokens'],
         },
         TransformERC20: {
-            contractType: ITransformERC20Contract,
+            contractType: ITransformERC20FeatureContract,
             fns: [
                 'transformERC20',
                 '_transformERC20',
@@ -86,11 +86,11 @@ blockchainTests.resets('Full migration', env => {
             ],
         },
         SignatureValidator: {
-            contractType: ISignatureValidatorContract,
+            contractType: ISignatureValidatorFeatureContract,
             fns: ['isValidHashSignature', 'validateHashSignature'],
         },
         MetaTransactions: {
-            contractType: IMetaTransactionsContract,
+            contractType: IMetaTransactionsFeatureContract,
             fns: [
                 'executeMetaTransaction',
                 'batchExecuteMetaTransactions',
@@ -181,7 +181,7 @@ blockchainTests.resets('Full migration', env => {
         let allowanceTarget: AllowanceTargetContract;
 
         before(async () => {
-            const contract = new ITokenSpenderContract(zeroEx.address, env.provider, env.txDefaults);
+            const contract = new ITokenSpenderFeatureContract(zeroEx.address, env.provider, env.txDefaults);
             allowanceTarget = new AllowanceTargetContract(
                 await contract.getAllowanceTarget().callAsync(),
                 env.provider,
@@ -199,10 +199,10 @@ blockchainTests.resets('Full migration', env => {
     });
 
     describe('TransformERC20', () => {
-        let feature: ITransformERC20Contract;
+        let feature: ITransformERC20FeatureContract;
 
         before(async () => {
-            feature = new ITransformERC20Contract(zeroEx.address, env.provider, env.txDefaults);
+            feature = new ITransformERC20FeatureContract(zeroEx.address, env.provider, env.txDefaults);
         });
 
         it('has the correct transformer deployer', async () => {

contracts/zero-ex/test/initial_migration_test.ts

@@ -4,10 +4,10 @@ import { hexUtils, ZeroExRevertErrors } from '@0x/utils';
 import { artifacts } from './artifacts';
 import { BootstrapFeatures, deployBootstrapFeaturesAsync } from './utils/migration';
 import {
-    IBootstrapContract,
+    IBootstrapFeatureContract,
     InitialMigrationContract,
-    IOwnableContract,
+    IOwnableFeatureContract,
-    SimpleFunctionRegistryContract,
+    SimpleFunctionRegistryFeatureContract,
     TestInitialMigrationContract,
     ZeroExContract,
 } from './wrappers';
@@ -16,7 +16,7 @@ blockchainTests.resets('Initial migration', env => {
     let owner: string;
     let zeroEx: ZeroExContract;
     let migrator: TestInitialMigrationContract;
-    let bootstrapFeature: IBootstrapContract;
+    let bootstrapFeature: IBootstrapFeatureContract;
     let features: BootstrapFeatures;
 
     before(async () => {
@@ -29,7 +29,7 @@ blockchainTests.resets('Initial migration', env => {
             artifacts,
             env.txDefaults.from as string,
         );
-        bootstrapFeature = new IBootstrapContract(
+        bootstrapFeature = new IBootstrapFeatureContract(
             await migrator.bootstrapFeature().callAsync(),
             env.provider,
             env.txDefaults,
@@ -82,10 +82,10 @@ blockchainTests.resets('Initial migration', env => {
     });
 
     describe('Ownable feature', () => {
-        let ownable: IOwnableContract;
+        let ownable: IOwnableFeatureContract;
 
         before(async () => {
-            ownable = new IOwnableContract(zeroEx.address, env.provider, env.txDefaults);
+            ownable = new IOwnableFeatureContract(zeroEx.address, env.provider, env.txDefaults);
         });
 
         it('has the correct owner', async () => {
@@ -95,10 +95,10 @@ blockchainTests.resets('Initial migration', env => {
     });
 
     describe('SimpleFunctionRegistry feature', () => {
-        let registry: SimpleFunctionRegistryContract;
+        let registry: SimpleFunctionRegistryFeatureContract;
 
         before(async () => {
-            registry = new SimpleFunctionRegistryContract(zeroEx.address, env.provider, env.txDefaults);
+            registry = new SimpleFunctionRegistryFeatureContract(zeroEx.address, env.provider, env.txDefaults);
         });
 
         it('_extendSelf() is deregistered', async () => {

contracts/zero-ex/test/transformer_deployer_test.ts

@@ -59,6 +59,12 @@ blockchainTests.resets('TransformerDeployer', env => {
             expect(await env.web3Wrapper.getBalanceInWeiAsync(targetAddress)).to.bignumber.eq(1);
         });
 
+        it('reverts if constructor throws', async () => {
+            const CONSTRUCTOR_FAIL_VALUE = new BigNumber(3333);
+            const tx = deployer.deploy(deployBytes).callAsync({ value: CONSTRUCTOR_FAIL_VALUE, from: authority });
+            return expect(tx).to.revertWith('TransformerDeployer/DEPLOY_FAILED');
+        });
+
         it('updates nonce', async () => {
             expect(await deployer.nonce().callAsync()).to.bignumber.eq(1);
             await deployer.deploy(deployBytes).awaitTransactionSuccessAsync({ from: authority });
@@ -82,6 +88,7 @@ blockchainTests.resets('TransformerDeployer', env => {
     });
 
     describe('kill()', () => {
+        const ethRecipient = randomAddress();
         let target: TestTransformerDeployerTransformerContract;
 
         before(async () => {
@@ -90,14 +97,16 @@ blockchainTests.resets('TransformerDeployer', env => {
             await deployer.deploy(deployBytes).awaitTransactionSuccessAsync({ from: authority });
         });
 
-        it('authority cannot call', async () => {
+        it('non-authority cannot call', async () => {
             const nonAuthority = randomAddress();
-            const tx = deployer.kill(target.address).callAsync({ from: nonAuthority });
+            const tx = deployer.kill(target.address, ethRecipient).callAsync({ from: nonAuthority });
             return expect(tx).to.revertWith(new AuthorizableRevertErrors.SenderNotAuthorizedError(nonAuthority));
         });
 
         it('authority can kill a contract', async () => {
-            const receipt = await deployer.kill(target.address).awaitTransactionSuccessAsync({ from: authority });
+            const receipt = await deployer
+                .kill(target.address, ethRecipient)
+                .awaitTransactionSuccessAsync({ from: authority });
             verifyEventsFromLogs(
                 receipt.logs,
                 [{ target: target.address, sender: authority }],

contracts/zero-ex/test/transformers/affiliate_fee_transformer_test.ts

@@ -86,7 +86,12 @@ blockchainTests.resets('AffiliateFeeTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), randomAddress(), data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                sender: randomAddress(),
+                taker: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq(ZERO_BALANCES);
         expect(await getBalancesAsync(recipients[0])).to.deep.eq({
@@ -112,7 +117,12 @@ blockchainTests.resets('AffiliateFeeTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), randomAddress(), data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                sender: randomAddress(),
+                taker: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq(ZERO_BALANCES);
         expect(await getBalancesAsync(recipients[0])).to.deep.eq({
@@ -138,7 +148,12 @@ blockchainTests.resets('AffiliateFeeTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), randomAddress(), data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                sender: randomAddress(),
+                taker: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq({
             tokenBalance: new BigNumber(1),

contracts/zero-ex/test/transformers/fill_quote_transformer_test.ts

@@ -32,6 +32,8 @@ const { NULL_ADDRESS, NULL_BYTES, MAX_UINT256, ZERO_AMOUNT } = constants;
 blockchainTests.resets('FillQuoteTransformer', env => {
     let maker: string;
     let feeRecipient: string;
+    let sender: string;
+    let taker: string;
     let exchange: TestFillQuoteTransformerExchangeContract;
     let bridge: TestFillQuoteTransformerBridgeContract;
     let transformer: FillQuoteTransformerContract;
@@ -44,7 +46,7 @@ blockchainTests.resets('FillQuoteTransformer', env => {
     const GAS_PRICE = 1337;
 
     before(async () => {
-        [maker, feeRecipient] = await env.getAccountAddressesAsync();
+        [maker, feeRecipient, sender, taker] = await env.getAccountAddressesAsync();
         exchange = await TestFillQuoteTransformerExchangeContract.deployFrom0xArtifactAsync(
             artifacts.TestFillQuoteTransformerExchange,
             env.provider,
@@ -60,6 +62,7 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                 balancerBridge: NULL_ADDRESS,
                 curveBridge: NULL_ADDRESS,
                 kyberBridge: NULL_ADDRESS,
+                mooniswapBridge: NULL_ADDRESS,
                 mStableBridge: NULL_ADDRESS,
                 oasisBridge: NULL_ADDRESS,
                 uniswapBridge: NULL_ADDRESS,
@@ -92,7 +95,7 @@ blockchainTests.resets('FillQuoteTransformer', env => {
         bridge = await TestFillQuoteTransformerBridgeContract.deployFrom0xArtifactAsync(
             artifacts.TestFillQuoteTransformerBridge,
             env.provider,
-            env.txDefaults,
+            { ...env.txDefaults, from: sender },
             artifacts,
         );
         [makerToken, takerToken, takerFeeToken] = await Promise.all(
@@ -270,6 +273,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
             signatures: [],
             maxOrderFillAmounts: [],
             fillAmount: MAX_UINT256,
+            refundReceiver: NULL_ADDRESS,
+            rfqtTakerAddress: NULL_ADDRESS,
             ...fields,
         });
     }
@@ -313,6 +318,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -334,6 +341,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -358,6 +367,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -380,6 +391,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -404,6 +417,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -430,6 +445,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -462,6 +479,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -486,6 +505,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -511,6 +532,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     takerTokenBalance,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -535,6 +558,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     takerTokenBalance,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -564,6 +589,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -586,6 +613,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -608,6 +637,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -627,6 +658,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -640,6 +673,80 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                 makerAssetBalance: qfr.makerAssetBought,
             });
         });
+
+        it('can refund unspent protocol fee to the `refundReceiver`', async () => {
+            const orders = _.times(2, () => createOrder());
+            const signatures = orders.map(() => encodeExchangeBehavior());
+            const qfr = getExpectedSellQuoteFillResults(orders);
+            const protocolFee = qfr.protocolFeePaid.plus(1);
+            const refundReceiver = randomAddress();
+            await host
+                .executeTransform(
+                    transformer.address,
+                    takerToken.address,
+                    qfr.takerAssetSpent,
+                    sender,
+                    taker,
+                    encodeTransformData({
+                        orders,
+                        signatures,
+                        refundReceiver,
+                    }),
+                )
+                .awaitTransactionSuccessAsync({ value: protocolFee });
+            const receiverBalancer = await env.web3Wrapper.getBalanceInWeiAsync(refundReceiver);
+            expect(receiverBalancer).to.bignumber.eq(1);
+        });
+
+        it('can refund unspent protocol fee to the taker', async () => {
+            const orders = _.times(2, () => createOrder());
+            const signatures = orders.map(() => encodeExchangeBehavior());
+            const qfr = getExpectedSellQuoteFillResults(orders);
+            const protocolFee = qfr.protocolFeePaid.plus(1);
+            const refundReceiver = randomAddress();
+            await host
+                .executeTransform(
+                    transformer.address,
+                    takerToken.address,
+                    qfr.takerAssetSpent,
+                    sender,
+                    refundReceiver, // taker = refundReceiver
+                    encodeTransformData({
+                        orders,
+                        signatures,
+                        // address(1) indicates taker
+                        refundReceiver: hexUtils.leftPad(1, 20),
+                    }),
+                )
+                .awaitTransactionSuccessAsync({ value: protocolFee });
+            const receiverBalancer = await env.web3Wrapper.getBalanceInWeiAsync(refundReceiver);
+            expect(receiverBalancer).to.bignumber.eq(1);
+        });
+
+        it('can refund unspent protocol fee to the sender', async () => {
+            const orders = _.times(2, () => createOrder());
+            const signatures = orders.map(() => encodeExchangeBehavior());
+            const qfr = getExpectedSellQuoteFillResults(orders);
+            const protocolFee = qfr.protocolFeePaid.plus(1);
+            const refundReceiver = randomAddress();
+            await host
+                .executeTransform(
+                    transformer.address,
+                    takerToken.address,
+                    qfr.takerAssetSpent,
+                    refundReceiver, // sender = refundReceiver
+                    taker,
+                    encodeTransformData({
+                        orders,
+                        signatures,
+                        // address(2) indicates sender
+                        refundReceiver: hexUtils.leftPad(2, 20),
+                    }),
+                )
+                .awaitTransactionSuccessAsync({ value: protocolFee });
+            const receiverBalancer = await env.web3Wrapper.getBalanceInWeiAsync(refundReceiver);
+            expect(receiverBalancer).to.bignumber.eq(1);
+        });
     });
 
     describe('buy quotes', () => {
@@ -652,6 +759,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -675,6 +784,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -701,6 +812,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -725,6 +838,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -751,6 +866,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -774,6 +891,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -804,6 +923,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -828,6 +949,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -852,6 +975,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -873,6 +998,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -900,6 +1027,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -926,6 +1055,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -952,6 +1083,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,
@@ -980,6 +1113,8 @@ blockchainTests.resets('FillQuoteTransformer', env => {
                     transformer.address,
                     takerToken.address,
                     qfr.takerAssetSpent,
+                    sender,
+                    taker,
                     encodeTransformData({
                         orders,
                         signatures,

contracts/zero-ex/test/transformers/pay_taker_transformer_test.ts

@@ -78,7 +78,12 @@ blockchainTests.resets('PayTakerTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), taker, data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                taker,
+                sender: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq(ZERO_BALANCES);
         expect(await getBalancesAsync(taker)).to.deep.eq({
@@ -96,7 +101,12 @@ blockchainTests.resets('PayTakerTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), taker, data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                taker,
+                sender: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq(ZERO_BALANCES);
         expect(await getBalancesAsync(taker)).to.deep.eq({
@@ -114,7 +124,12 @@ blockchainTests.resets('PayTakerTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), taker, data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                taker,
+                sender: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq(ZERO_BALANCES);
         expect(await getBalancesAsync(taker)).to.deep.eq({
@@ -132,7 +147,12 @@ blockchainTests.resets('PayTakerTransformer', env => {
         await mintHostTokensAsync(amounts[0]);
         await sendEtherAsync(host.address, amounts[1]);
         await host
-            .rawExecuteTransform(transformer.address, hexUtils.random(), taker, data)
+            .rawExecuteTransform(transformer.address, {
+                data,
+                callDataHash: hexUtils.random(),
+                taker,
+                sender: randomAddress(),
+            })
             .awaitTransactionSuccessAsync();
         expect(await getBalancesAsync(host.address)).to.deep.eq({
             tokenBalance: amounts[0].minus(amounts[0].dividedToIntegerBy(2)),

contracts/zero-ex/test/wrappers.ts

@@ -5,15 +5,16 @@
  */
 export * from '../test/generated-wrappers/affiliate_fee_transformer';
 export * from '../test/generated-wrappers/allowance_target';
-export * from '../test/generated-wrappers/bootstrap';
+export * from '../test/generated-wrappers/bootstrap_feature';
 export * from '../test/generated-wrappers/bridge_adapter';
 export * from '../test/generated-wrappers/fill_quote_transformer';
 export * from '../test/generated-wrappers/fixin_common';
 export * from '../test/generated-wrappers/fixin_e_i_p712';
+export * from '../test/generated-wrappers/fixin_reentrancy_guard';
 export * from '../test/generated-wrappers/flash_wallet';
 export * from '../test/generated-wrappers/full_migration';
 export * from '../test/generated-wrappers/i_allowance_target';
-export * from '../test/generated-wrappers/i_bootstrap';
+export * from '../test/generated-wrappers/i_bootstrap_feature';
 export * from '../test/generated-wrappers/i_bridge_adapter';
 export * from '../test/generated-wrappers/i_erc20_bridge';
 export * from '../test/generated-wrappers/i_erc20_transformer';
@@ -21,13 +22,13 @@ export * from '../test/generated-wrappers/i_exchange';
 export * from '../test/generated-wrappers/i_feature';
 export * from '../test/generated-wrappers/i_flash_wallet';
 export * from '../test/generated-wrappers/i_gas_token';
-export * from '../test/generated-wrappers/i_meta_transactions';
+export * from '../test/generated-wrappers/i_meta_transactions_feature';
-export * from '../test/generated-wrappers/i_ownable';
+export * from '../test/generated-wrappers/i_ownable_feature';
-export * from '../test/generated-wrappers/i_signature_validator';
+export * from '../test/generated-wrappers/i_signature_validator_feature';
-export * from '../test/generated-wrappers/i_simple_function_registry';
+export * from '../test/generated-wrappers/i_simple_function_registry_feature';
 export * from '../test/generated-wrappers/i_test_simple_function_registry_feature';
-export * from '../test/generated-wrappers/i_token_spender';
+export * from '../test/generated-wrappers/i_token_spender_feature';
-export * from '../test/generated-wrappers/i_transform_erc20';
+export * from '../test/generated-wrappers/i_transform_erc20_feature';
 export * from '../test/generated-wrappers/i_zero_ex';
 export * from '../test/generated-wrappers/initial_migration';
 export * from '../test/generated-wrappers/lib_bootstrap';
@@ -40,6 +41,7 @@ export * from '../test/generated-wrappers/lib_ownable_rich_errors';
 export * from '../test/generated-wrappers/lib_ownable_storage';
 export * from '../test/generated-wrappers/lib_proxy_rich_errors';
 export * from '../test/generated-wrappers/lib_proxy_storage';
+export * from '../test/generated-wrappers/lib_reentrancy_guard_storage';
 export * from '../test/generated-wrappers/lib_signature_rich_errors';
 export * from '../test/generated-wrappers/lib_signed_call_data';
 export * from '../test/generated-wrappers/lib_simple_function_registry_rich_errors';
@@ -50,20 +52,22 @@ export * from '../test/generated-wrappers/lib_token_spender_storage';
 export * from '../test/generated-wrappers/lib_transform_erc20_rich_errors';
 export * from '../test/generated-wrappers/lib_transform_erc20_storage';
 export * from '../test/generated-wrappers/lib_wallet_rich_errors';
-export * from '../test/generated-wrappers/meta_transactions';
+export * from '../test/generated-wrappers/log_metadata_transformer';
+export * from '../test/generated-wrappers/meta_transactions_feature';
 export * from '../test/generated-wrappers/mixin_adapter_addresses';
 export * from '../test/generated-wrappers/mixin_balancer';
 export * from '../test/generated-wrappers/mixin_curve';
 export * from '../test/generated-wrappers/mixin_kyber';
 export * from '../test/generated-wrappers/mixin_m_stable';
+export * from '../test/generated-wrappers/mixin_mooniswap';
 export * from '../test/generated-wrappers/mixin_oasis';
 export * from '../test/generated-wrappers/mixin_uniswap';
 export * from '../test/generated-wrappers/mixin_uniswap_v2';
 export * from '../test/generated-wrappers/mixin_zero_ex_bridge';
-export * from '../test/generated-wrappers/ownable';
+export * from '../test/generated-wrappers/ownable_feature';
 export * from '../test/generated-wrappers/pay_taker_transformer';
-export * from '../test/generated-wrappers/signature_validator';
+export * from '../test/generated-wrappers/signature_validator_feature';
-export * from '../test/generated-wrappers/simple_function_registry';
+export * from '../test/generated-wrappers/simple_function_registry_feature';
 export * from '../test/generated-wrappers/test_call_target';
 export * from '../test/generated-wrappers/test_delegate_caller';
 export * from '../test/generated-wrappers/test_fill_quote_transformer_bridge';
@@ -86,8 +90,8 @@ export * from '../test/generated-wrappers/test_transformer_host';
 export * from '../test/generated-wrappers/test_weth';
 export * from '../test/generated-wrappers/test_weth_transformer_host';
 export * from '../test/generated-wrappers/test_zero_ex_feature';
-export * from '../test/generated-wrappers/token_spender';
+export * from '../test/generated-wrappers/token_spender_feature';
-export * from '../test/generated-wrappers/transform_erc20';
+export * from '../test/generated-wrappers/transform_erc20_feature';
 export * from '../test/generated-wrappers/transformer';
 export * from '../test/generated-wrappers/transformer_deployer';
 export * from '../test/generated-wrappers/weth_transformer';

contracts/zero-ex/test/zero_ex_test.ts

@@ -7,8 +7,8 @@ import { artifacts } from './artifacts';
 import { initialMigrateAsync } from './utils/migration';
 import {
     IFeatureContract,
-    IOwnableContract,
+    IOwnableFeatureContract,
-    ISimpleFunctionRegistryContract,
+    ISimpleFunctionRegistryFeatureContract,
     TestZeroExFeatureContract,
     TestZeroExFeatureEvents,
 } from './wrappers';
@@ -16,15 +16,15 @@ import {
 blockchainTests.resets('ZeroEx contract', env => {
     let owner: string;
     let zeroEx: ZeroExContract;
-    let ownable: IOwnableContract;
+    let ownable: IOwnableFeatureContract;
-    let registry: ISimpleFunctionRegistryContract;
+    let registry: ISimpleFunctionRegistryFeatureContract;
     let testFeature: TestZeroExFeatureContract;
 
     before(async () => {
         [owner] = await env.getAccountAddressesAsync();
         zeroEx = await initialMigrateAsync(owner, env.provider, env.txDefaults);
-        ownable = new IOwnableContract(zeroEx.address, env.provider, env.txDefaults);
+        ownable = new IOwnableFeatureContract(zeroEx.address, env.provider, env.txDefaults);
-        registry = new ISimpleFunctionRegistryContract(zeroEx.address, env.provider, env.txDefaults);
+        registry = new ISimpleFunctionRegistryFeatureContract(zeroEx.address, env.provider, env.txDefaults);
         testFeature = new TestZeroExFeatureContract(zeroEx.address, env.provider, env.txDefaults);
         // Register test features.
         const testFeatureImpl = await TestZeroExFeatureContract.deployFrom0xArtifactAsync(

contracts/zero-ex/tsconfig.json

@@ -10,32 +10,34 @@
         "generated-artifacts/IAllowanceTarget.json",
         "generated-artifacts/IERC20Transformer.json",
         "generated-artifacts/IFlashWallet.json",
-        "generated-artifacts/IOwnable.json",
+        "generated-artifacts/IOwnableFeature.json",
-        "generated-artifacts/ISimpleFunctionRegistry.json",
+        "generated-artifacts/ISimpleFunctionRegistryFeature.json",
-        "generated-artifacts/ITokenSpender.json",
+        "generated-artifacts/ITokenSpenderFeature.json",
-        "generated-artifacts/ITransformERC20.json",
+        "generated-artifacts/ITransformERC20Feature.json",
         "generated-artifacts/IZeroEx.json",
         "generated-artifacts/InitialMigration.json",
-        "generated-artifacts/MetaTransactions.json",
+        "generated-artifacts/LogMetadataTransformer.json",
-        "generated-artifacts/Ownable.json",
+        "generated-artifacts/MetaTransactionsFeature.json",
+        "generated-artifacts/OwnableFeature.json",
         "generated-artifacts/PayTakerTransformer.json",
-        "generated-artifacts/SignatureValidator.json",
+        "generated-artifacts/SignatureValidatorFeature.json",
-        "generated-artifacts/SimpleFunctionRegistry.json",
+        "generated-artifacts/SimpleFunctionRegistryFeature.json",
-        "generated-artifacts/TokenSpender.json",
+        "generated-artifacts/TokenSpenderFeature.json",
-        "generated-artifacts/TransformERC20.json",
+        "generated-artifacts/TransformERC20Feature.json",
         "generated-artifacts/WethTransformer.json",
         "generated-artifacts/ZeroEx.json",
         "test/generated-artifacts/AffiliateFeeTransformer.json",
         "test/generated-artifacts/AllowanceTarget.json",
-        "test/generated-artifacts/Bootstrap.json",
+        "test/generated-artifacts/BootstrapFeature.json",
         "test/generated-artifacts/BridgeAdapter.json",
         "test/generated-artifacts/FillQuoteTransformer.json",
         "test/generated-artifacts/FixinCommon.json",
         "test/generated-artifacts/FixinEIP712.json",
+        "test/generated-artifacts/FixinReentrancyGuard.json",
         "test/generated-artifacts/FlashWallet.json",
         "test/generated-artifacts/FullMigration.json",
         "test/generated-artifacts/IAllowanceTarget.json",
-        "test/generated-artifacts/IBootstrap.json",
+        "test/generated-artifacts/IBootstrapFeature.json",
         "test/generated-artifacts/IBridgeAdapter.json",
         "test/generated-artifacts/IERC20Bridge.json",
         "test/generated-artifacts/IERC20Transformer.json",
@@ -43,13 +45,13 @@
         "test/generated-artifacts/IFeature.json",
         "test/generated-artifacts/IFlashWallet.json",
         "test/generated-artifacts/IGasToken.json",
-        "test/generated-artifacts/IMetaTransactions.json",
+        "test/generated-artifacts/IMetaTransactionsFeature.json",
-        "test/generated-artifacts/IOwnable.json",
+        "test/generated-artifacts/IOwnableFeature.json",
-        "test/generated-artifacts/ISignatureValidator.json",
+        "test/generated-artifacts/ISignatureValidatorFeature.json",
-        "test/generated-artifacts/ISimpleFunctionRegistry.json",
+        "test/generated-artifacts/ISimpleFunctionRegistryFeature.json",
         "test/generated-artifacts/ITestSimpleFunctionRegistryFeature.json",
-        "test/generated-artifacts/ITokenSpender.json",
+        "test/generated-artifacts/ITokenSpenderFeature.json",
-        "test/generated-artifacts/ITransformERC20.json",
+        "test/generated-artifacts/ITransformERC20Feature.json",
         "test/generated-artifacts/IZeroEx.json",
         "test/generated-artifacts/InitialMigration.json",
         "test/generated-artifacts/LibBootstrap.json",
@@ -62,6 +64,7 @@
         "test/generated-artifacts/LibOwnableStorage.json",
         "test/generated-artifacts/LibProxyRichErrors.json",
         "test/generated-artifacts/LibProxyStorage.json",
+        "test/generated-artifacts/LibReentrancyGuardStorage.json",
         "test/generated-artifacts/LibSignatureRichErrors.json",
         "test/generated-artifacts/LibSignedCallData.json",
         "test/generated-artifacts/LibSimpleFunctionRegistryRichErrors.json",
@@ -72,20 +75,22 @@
         "test/generated-artifacts/LibTransformERC20RichErrors.json",
         "test/generated-artifacts/LibTransformERC20Storage.json",
         "test/generated-artifacts/LibWalletRichErrors.json",
-        "test/generated-artifacts/MetaTransactions.json",
+        "test/generated-artifacts/LogMetadataTransformer.json",
+        "test/generated-artifacts/MetaTransactionsFeature.json",
         "test/generated-artifacts/MixinAdapterAddresses.json",
         "test/generated-artifacts/MixinBalancer.json",
         "test/generated-artifacts/MixinCurve.json",
         "test/generated-artifacts/MixinKyber.json",
         "test/generated-artifacts/MixinMStable.json",
+        "test/generated-artifacts/MixinMooniswap.json",
         "test/generated-artifacts/MixinOasis.json",
         "test/generated-artifacts/MixinUniswap.json",
         "test/generated-artifacts/MixinUniswapV2.json",
         "test/generated-artifacts/MixinZeroExBridge.json",
-        "test/generated-artifacts/Ownable.json",
+        "test/generated-artifacts/OwnableFeature.json",
         "test/generated-artifacts/PayTakerTransformer.json",
-        "test/generated-artifacts/SignatureValidator.json",
+        "test/generated-artifacts/SignatureValidatorFeature.json",
-        "test/generated-artifacts/SimpleFunctionRegistry.json",
+        "test/generated-artifacts/SimpleFunctionRegistryFeature.json",
         "test/generated-artifacts/TestCallTarget.json",
         "test/generated-artifacts/TestDelegateCaller.json",
         "test/generated-artifacts/TestFillQuoteTransformerBridge.json",
@@ -108,8 +113,8 @@
         "test/generated-artifacts/TestWeth.json",
         "test/generated-artifacts/TestWethTransformerHost.json",
         "test/generated-artifacts/TestZeroExFeature.json",
-        "test/generated-artifacts/TokenSpender.json",
+        "test/generated-artifacts/TokenSpenderFeature.json",
-        "test/generated-artifacts/TransformERC20.json",
+        "test/generated-artifacts/TransformERC20Feature.json",
         "test/generated-artifacts/Transformer.json",
         "test/generated-artifacts/TransformerDeployer.json",
         "test/generated-artifacts/WethTransformer.json",

packages/asset-swapper/CHANGELOG.json

@@ -85,6 +85,22 @@
             {
                 "note": "Enable Quote Report to be generated with an option `shouldGenerateQuoteReport`. Default is `false`",
                 "pr": 2687
+            },
+            {
+                "note": "Add `refundReceiver` to `ExchangeProxySwapQuoteConsumer` options.",
+                "pr": 2657
+            },
+            {
+                "note": "Use `IZeroExContract` in EP swap quote consumer.",
+                "pr": 2657
+            },
+            {
+                "note": "Set `rfqtTakerAddress` to null in EP consumer",
+                "pr": 2692
+            },
+            {
+                "note": "Return Mooniswap pool in sampler and encode it in bridge data",
+                "pr": 2692
             }
         ]
     },

packages/asset-swapper/contracts/src/MooniswapSampler.sol

@@ -46,50 +46,69 @@ contract MooniswapSampler is
     )
         public
         view
-        returns (uint256[] memory makerTokenAmounts)
+        returns (IMooniswap pool, uint256[] memory makerTokenAmounts)
     {
         _assertValidPair(makerToken, takerToken);
         uint256 numSamples = takerTokenAmounts.length;
         makerTokenAmounts = new uint256[](numSamples);
 
-        address _takerToken = takerToken == _getWethAddress() ? address(0) : takerToken;
+        address mooniswapTakerToken = takerToken == _getWethAddress() ? address(0) : takerToken;
-        address _makerToken = makerToken == _getWethAddress() ? address(0) : makerToken;
+        address mooniswapMakerToken = makerToken == _getWethAddress() ? address(0) : makerToken;
-        // Find the pool for the pair, ETH is represented
-        // as address(0)
-        IMooniswap pool = IMooniswap(
-            IMooniswapRegistry(_getMooniswapAddress()).pools(_takerToken, _makerToken)
-        );
-        // If there is no pool then return early
-        if (address(pool) == address(0)) {
-            return makerTokenAmounts;
-        }
-
-        uint256 poolBalance = _takerToken == address(0) ? address(pool).balance : IERC20Token(_takerToken).balanceOf(address(pool));
 
         for (uint256 i = 0; i < numSamples; i++) {
-            // If the pool balance is smaller than the sell amount
+            uint256 buyAmount = sampleSingleSellFromMooniswapPool(
-            // don't sample to avoid multiplication overflow in buys
+                mooniswapTakerToken,
-            if (poolBalance < takerTokenAmounts[i]) {
+                mooniswapMakerToken,
-                break;
-            }
-            (bool didSucceed, bytes memory resultData) =
-                address(pool).staticcall.gas(MOONISWAP_CALL_GAS)(
-                    abi.encodeWithSelector(
-                        IMooniswap(0).getReturn.selector,
-                        _takerToken,
-                        _makerToken,
                 takerTokenAmounts[i]
-                    ));
+            );
-            uint256 buyAmount = 0;
-            if (didSucceed) {
-                buyAmount = abi.decode(resultData, (uint256));
-            }
             // Exit early if the amount is too high for the source to serve
             if (buyAmount == 0) {
                 break;
             }
             makerTokenAmounts[i] = buyAmount;
         }
+
+        pool = IMooniswap(
+            IMooniswapRegistry(_getMooniswapAddress()).pools(mooniswapTakerToken, mooniswapMakerToken)
+        );
+    }
+
+    function sampleSingleSellFromMooniswapPool(
+        address mooniswapTakerToken,
+        address mooniswapMakerToken,
+        uint256 takerTokenAmount
+    )
+        public
+        view
+        returns (uint256 makerTokenAmount)
+    {
+        // Find the pool for the pair.
+        IMooniswap pool = IMooniswap(
+            IMooniswapRegistry(_getMooniswapAddress()).pools(mooniswapTakerToken, mooniswapMakerToken)
+        );
+        // If there is no pool then return early
+        if (address(pool) == address(0)) {
+            return makerTokenAmount;
+        }
+        uint256 poolBalance = mooniswapTakerToken == address(0)
+            ? address(pool).balance
+            : IERC20Token(mooniswapTakerToken).balanceOf(address(pool));
+        // If the pool balance is smaller than the sell amount
+        // don't sample to avoid multiplication overflow in buys
+        if (poolBalance < takerTokenAmount) {
+            return makerTokenAmount;
+        }
+        (bool didSucceed, bytes memory resultData) =
+            address(pool).staticcall.gas(MOONISWAP_CALL_GAS)(
+                abi.encodeWithSelector(
+                    pool.getReturn.selector,
+                    mooniswapTakerToken,
+                    mooniswapMakerToken,
+                    takerTokenAmount
+                ));
+        if (didSucceed) {
+            makerTokenAmount = abi.decode(resultData, (uint256));
+        }
     }
 
     /// @dev Sample buy quotes from Mooniswap.
@@ -105,16 +124,27 @@ contract MooniswapSampler is
     )
         public
         view
-        returns (uint256[] memory takerTokenAmounts)
+        returns (IMooniswap pool, uint256[] memory takerTokenAmounts)
     {
-        return _sampleApproximateBuys(
+        _assertValidPair(makerToken, takerToken);
+        uint256 numSamples = makerTokenAmounts.length;
+        takerTokenAmounts = new uint256[](numSamples);
+
+        address mooniswapTakerToken = takerToken == _getWethAddress() ? address(0) : takerToken;
+        address mooniswapMakerToken = makerToken == _getWethAddress() ? address(0) : makerToken;
+
+        takerTokenAmounts = _sampleApproximateBuys(
             ApproximateBuyQuoteOpts({
-                makerTokenData: abi.encode(makerToken),
+                makerTokenData: abi.encode(mooniswapMakerToken),
-                takerTokenData: abi.encode(takerToken),
+                takerTokenData: abi.encode(mooniswapTakerToken),
                 getSellQuoteCallback: _sampleSellForApproximateBuyFromMooniswap
             }),
             makerTokenAmounts
         );
+
+        pool = IMooniswap(
+            IMooniswapRegistry(_getMooniswapAddress()).pools(mooniswapTakerToken, mooniswapMakerToken)
+        );
     }
 
     function _sampleSellForApproximateBuyFromMooniswap(
@@ -126,21 +156,12 @@ contract MooniswapSampler is
         view
         returns (uint256 buyAmount)
     {
-        (address takerToken) =
+        address mooniswapTakerToken = abi.decode(takerTokenData, (address));
-            abi.decode(takerTokenData, (address));
+        address mooniswapMakerToken = abi.decode(makerTokenData, (address));
-        (address makerToken) =
+        return sampleSingleSellFromMooniswapPool(
-            abi.decode(makerTokenData, (address));
+            mooniswapTakerToken,
-        (bool success, bytes memory resultData) =
+            mooniswapMakerToken,
-            address(this).staticcall(abi.encodeWithSelector(
+            sellAmount
-                this.sampleSellsFromMooniswap.selector,
+        );
-                takerToken,
-                makerToken,
-                _toSingleValueArray(sellAmount)
-            ));
-        if (!success) {
-            return 0;
-        }
-        // solhint-disable-next-line indent
-        return abi.decode(resultData, (uint256[]))[0];
     }
 }

packages/asset-swapper/src/constants.ts

@@ -68,6 +68,7 @@ const DEFAULT_EXCHANGE_PROXY_EXTENSION_CONTRACT_OPTS: ExchangeProxyContractOpts
         buyTokenFeeAmount: ZERO_AMOUNT,
         sellTokenFeeAmount: ZERO_AMOUNT,
     },
+    refundReceiver: NULL_ADDRESS,
 };
 
 const DEFAULT_FORWARDER_SWAP_QUOTE_EXECUTE_OPTS: SwapQuoteExecutionOpts = DEFAULT_FORWARDER_SWAP_QUOTE_GET_OPTS;

packages/asset-swapper/src/index.ts

@@ -89,6 +89,7 @@ export {
     AffiliateFee,
     CalldataInfo,
     ExchangeProxyContractOpts,
+    ExchangeProxyRefundReceiver,
     ExtensionContractType,
     ForwarderExtensionContractOpts,
     GetExtensionContractTypeOpts,
@@ -139,6 +140,7 @@ export {
     LiquidityProviderFillData,
     MarketDepth,
     MarketDepthSide,
+    MooniswapFillData,
     MultiBridgeFillData,
     MultiHopFillData,
     NativeCollapsedFill,

packages/asset-swapper/src/quote_consumers/exchange_proxy_swap_quote_consumer.ts

@@ -1,5 +1,5 @@
 import { ContractAddresses } from '@0x/contract-addresses';
-import { ITransformERC20Contract } from '@0x/contract-wrappers';
+import { IZeroExContract } from '@0x/contract-wrappers';
 import {
     encodeAffiliateFeeTransformerData,
     encodeFillQuoteTransformerData,
@@ -7,10 +7,10 @@ import {
     encodeWethTransformerData,
     ETH_TOKEN_ADDRESS,
     FillQuoteTransformerSide,
+    findTransformerNonce,
 } from '@0x/order-utils';
 import { BigNumber, providerUtils } from '@0x/utils';
 import { SupportedProvider, ZeroExProvider } from '@0x/web3-wrapper';
-import * as ethjs from 'ethereumjs-util';
 import * as _ from 'lodash';
 
 import { constants } from '../constants';
@@ -32,7 +32,6 @@ import { getTokenFromAssetData } from '../utils/utils';
 // tslint:disable-next-line:custom-no-magic-numbers
 const MAX_UINT256 = new BigNumber(2).pow(256).minus(1);
 const { NULL_ADDRESS } = constants;
-const MAX_NONCE_GUESSES = 2048;
 
 export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
     public readonly provider: ZeroExProvider;
@@ -44,7 +43,7 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
         affiliateFeeTransformer: number;
     };
 
-    private readonly _transformFeature: ITransformERC20Contract;
+    private readonly _exchangeProxy: IZeroExContract;
 
     constructor(
         supportedProvider: SupportedProvider,
@@ -57,7 +56,7 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
         this.provider = provider;
         this.chainId = chainId;
         this.contractAddresses = contractAddresses;
-        this._transformFeature = new ITransformERC20Contract(contractAddresses.exchangeProxy, supportedProvider);
+        this._exchangeProxy = new IZeroExContract(contractAddresses.exchangeProxy, supportedProvider);
         this.transformerNonces = {
             wethTransformer: findTransformerNonce(
                 contractAddresses.transformers.wethTransformer,
@@ -84,7 +83,7 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
     ): Promise<CalldataInfo> {
         assert.isValidSwapQuote('quote', quote);
         // tslint:disable-next-line:no-object-literal-type-assertion
-        const { affiliateFee, isFromETH, isToETH } = {
+        const { refundReceiver, affiliateFee, isFromETH, isToETH } = {
             ...constants.DEFAULT_EXCHANGE_PROXY_EXTENSION_CONTRACT_OPTS,
             ...opts.extensionContractOpts,
         } as ExchangeProxyContractOpts;
@@ -116,8 +115,10 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
                     sellToken,
                     buyToken: intermediateToken,
                     side: FillQuoteTransformerSide.Sell,
+                    refundReceiver: refundReceiver || NULL_ADDRESS,
                     fillAmount: firstHopOrder.takerAssetAmount,
                     maxOrderFillAmounts: [],
+                    rfqtTakerAddress: NULL_ADDRESS,
                     orders: [firstHopOrder],
                     signatures: [firstHopOrder.signature],
                 }),
@@ -125,11 +126,13 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
             transforms.push({
                 deploymentNonce: this.transformerNonces.fillQuoteTransformer,
                 data: encodeFillQuoteTransformerData({
-                    sellToken: intermediateToken,
                     buyToken,
+                    sellToken: intermediateToken,
+                    refundReceiver: refundReceiver || NULL_ADDRESS,
                     side: FillQuoteTransformerSide.Sell,
                     fillAmount: MAX_UINT256,
                     maxOrderFillAmounts: [],
+                    rfqtTakerAddress: NULL_ADDRESS,
                     orders: [secondHopOrder],
                     signatures: [secondHopOrder.signature],
                 }),
@@ -140,9 +143,11 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
                 data: encodeFillQuoteTransformerData({
                     sellToken,
                     buyToken,
+                    refundReceiver: refundReceiver || NULL_ADDRESS,
                     side: isBuyQuote(quote) ? FillQuoteTransformerSide.Buy : FillQuoteTransformerSide.Sell,
                     fillAmount: isBuyQuote(quote) ? quote.makerAssetFillAmount : quote.takerAssetFillAmount,
                     maxOrderFillAmounts: [],
+                    rfqtTakerAddress: NULL_ADDRESS,
                     orders: quote.orders,
                     signatures: quote.orders.map(o => o.signature),
                 }),
@@ -192,7 +197,7 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
         });
 
         const minBuyAmount = BigNumber.max(0, quote.worstCaseQuoteInfo.makerAssetAmount.minus(buyTokenFeeAmount));
-        const calldataHexString = this._transformFeature
+        const calldataHexString = this._exchangeProxy
             .transformERC20(
                 isFromETH ? ETH_TOKEN_ADDRESS : sellToken,
                 isToETH ? ETH_TOKEN_ADDRESS : buyToken,
@@ -210,7 +215,7 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
         return {
             calldataHexString,
             ethAmount,
-            toAddress: this._transformFeature.address,
+            toAddress: this._exchangeProxy.address,
             allowanceTarget: this.contractAddresses.exchangeProxyAllowanceTarget,
         };
     }
@@ -227,32 +232,3 @@ export class ExchangeProxySwapQuoteConsumer implements SwapQuoteConsumerBase {
 function isBuyQuote(quote: SwapQuote): quote is MarketBuySwapQuote {
     return quote.type === MarketOperation.Buy;
 }
-
-/**
- * Find the nonce for a transformer given its deployer.
- * If `deployer` is the null address, zero will always be returned.
- */
-export function findTransformerNonce(transformer: string, deployer: string = NULL_ADDRESS): number {
-    if (deployer === NULL_ADDRESS) {
-        return 0;
-    }
-    const lowercaseTransformer = transformer.toLowerCase();
-    // Try to guess the nonce.
-    for (let nonce = 0; nonce < MAX_NONCE_GUESSES; ++nonce) {
-        const deployedAddress = getTransformerAddress(deployer, nonce);
-        if (deployedAddress === lowercaseTransformer) {
-            return nonce;
-        }
-    }
-    throw new Error(`${deployer} did not deploy ${transformer}!`);
-}
-
-/**
- * Compute the deployed address for a transformer given a deployer and nonce.
- */
-export function getTransformerAddress(deployer: string, nonce: number): string {
-    return ethjs.bufferToHex(
-        // tslint:disable-next-line: custom-no-magic-numbers
-        ethjs.rlphash([deployer, nonce] as any).slice(12),
-    );
-}

packages/asset-swapper/src/types.ts

@@ -135,15 +135,31 @@ export interface AffiliateFee {
     sellTokenFeeAmount: BigNumber;
 }
 
+/**
+ * Automatically resolved protocol fee refund receiver addresses.
+ */
+export enum ExchangeProxyRefundReceiver {
+    // Refund to the taker address.
+    Taker = '0x0000000000000000000000000000000000000001',
+    // Refund to the sender address.
+    Sender = '0x0000000000000000000000000000000000000002',
+}
+
 /**
  * @param isFromETH Whether the input token is ETH.
  * @param isToETH Whether the output token is ETH.
  * @param affiliateFee Fee denominated in taker or maker asset to send to specified recipient.
+ * @param refundReceiver The receiver of unspent protocol fees.
+ *        May be a valid address or one of:
+ *        `address(0)`: Stay in flash wallet.
+ *        `address(1)`: Send to the taker.
+ *        `address(2)`: Send to the sender (caller of `transformERC20()`).
  */
 export interface ExchangeProxyContractOpts {
     isFromETH: boolean;
     isToETH: boolean;
     affiliateFee: AffiliateFee;
+    refundReceiver: string | ExchangeProxyRefundReceiver;
 }
 
 export interface GetExtensionContractTypeOpts {

packages/asset-swapper/src/utils/market_operation_utils/orders.ts

@@ -29,6 +29,7 @@ import {
     Fill,
     KyberFillData,
     LiquidityProviderFillData,
+    MooniswapFillData,
     MultiBridgeFillData,
     MultiHopFillData,
     NativeCollapsedFill,
@@ -304,6 +305,14 @@ function createBridgeOrder(
                 createKyberBridgeData(takerToken, kyberFillData.hint),
             );
             break;
+        case ERC20BridgeSource.Mooniswap:
+            const mooniswapFillData = (fill as CollapsedFill<MooniswapFillData>).fillData!; // tslint:disable-line:no-non-null-assertion
+            makerAssetData = assetDataUtils.encodeERC20BridgeAssetData(
+                makerToken,
+                bridgeAddress,
+                createMooniswapBridgeData(takerToken, mooniswapFillData.poolAddress),
+            );
+            break;
         default:
             makerAssetData = assetDataUtils.encodeERC20BridgeAssetData(
                 makerToken,
@@ -407,6 +416,14 @@ function createKyberBridgeData(fromTokenAddress: string, hint: string): string {
     return encoder.encode({ fromTokenAddress, hint });
 }
 
+function createMooniswapBridgeData(takerToken: string, poolAddress: string): string {
+    const encoder = AbiEncoder.create([
+        { name: 'takerToken', type: 'address' },
+        { name: 'poolAddress', type: 'address' },
+    ]);
+    return encoder.encode({ takerToken, poolAddress });
+}
+
 function createCurveBridgeData(
     curveAddress: string,
     exchangeFunctionSelector: string,

packages/asset-swapper/src/utils/market_operation_utils/sampler_operations.ts

@@ -23,6 +23,7 @@ import {
     HopInfo,
     KyberFillData,
     LiquidityProviderFillData,
+    MooniswapFillData,
     MultiBridgeFillData,
     MultiHopFillData,
     SourceQuoteOperation,
@@ -446,6 +447,14 @@ export class SamplerOperations {
             contract: this._samplerContract,
             function: this._samplerContract.sampleSellsFromMooniswap,
             params: [takerToken, makerToken, takerFillAmounts],
+            callback: (callResults: string, fillData: MooniswapFillData): BigNumber[] => {
+                const [poolAddress, samples] = this._samplerContract.getABIDecodedReturnData<[string, BigNumber[]]>(
+                    'sampleSellsFromMooniswap',
+                    callResults,
+                );
+                fillData.poolAddress = poolAddress;
+                return samples;
+            },
         });
     }
 
@@ -459,6 +468,14 @@ export class SamplerOperations {
             contract: this._samplerContract,
             function: this._samplerContract.sampleBuysFromMooniswap,
             params: [takerToken, makerToken, makerFillAmounts],
+            callback: (callResults: string, fillData: MooniswapFillData): BigNumber[] => {
+                const [poolAddress, samples] = this._samplerContract.getABIDecodedReturnData<[string, BigNumber[]]>(
+                    'sampleBuysFromMooniswap',
+                    callResults,
+                );
+                fillData.poolAddress = poolAddress;
+                return samples;
+            },
         });
     }
 

packages/asset-swapper/src/utils/market_operation_utils/types.ts

@@ -113,6 +113,10 @@ export interface KyberFillData extends FillData {
     reserveId: string;
 }
 
+export interface MooniswapFillData extends FillData {
+    poolAddress: string;
+}
+
 export interface Quote<TFillData = FillData> {
     amount: BigNumber;
     fillData?: TFillData;

packages/asset-swapper/test/exchange_proxy_swap_quote_consumer_test.ts

@@ -8,6 +8,7 @@ import {
     decodeWethTransformerData,
     ETH_TOKEN_ADDRESS,
     FillQuoteTransformerSide,
+    getTransformerAddress,
 } from '@0x/order-utils';
 import { Order } from '@0x/types';
 import { AbiEncoder, BigNumber, hexUtils } from '@0x/utils';
@@ -16,10 +17,7 @@ import * as _ from 'lodash';
 import 'mocha';
 
 import { constants } from '../src/constants';
-import {
+import { ExchangeProxySwapQuoteConsumer } from '../src/quote_consumers/exchange_proxy_swap_quote_consumer';
-    ExchangeProxySwapQuoteConsumer,
-    getTransformerAddress,
-} from '../src/quote_consumers/exchange_proxy_swap_quote_consumer';
 import { MarketBuySwapQuote, MarketOperation, MarketSellSwapQuote } from '../src/types';
 import { OptimizedMarketOrder } from '../src/utils/market_operation_utils/types';
 

packages/asset-swapper/test/quote_simulation_test.ts

@@ -24,8 +24,8 @@ describe('quote_simulation tests', async () => {
     const DEFAULT_TAKER_ASSET_DATA = assetDataUtils.encodeERC20AssetData(TAKER_TOKEN);
     const GAS_SCHEDULE = { [ERC20BridgeSource.Native]: _.constant(1) };
 
-    // Check if two numbers are within `maxError` error rate within each other (default 1 bps).
+    // Check if two numbers are within `maxError` error rate within each other.
-    function assertRoughlyEquals(n1: BigNumber, n2: BigNumber, maxError: BigNumber | number = 1e-12): void {
+    function assertRoughlyEquals(n1: BigNumber, n2: BigNumber, maxError: BigNumber | number = 1e-10): void {
         // |n2-n1| / max(|n1|, |n2|)
         const err = n2
             .minus(n1)