Add async suffix

[website] Remove @next dir, remove unused files.

.circleci/config.yml

@@ -18,6 +18,7 @@ jobs:
                   name: yarn
                   command: yarn --frozen-lockfile install || yarn --frozen-lockfile install
             - run: yarn build:ci:no_website
+            - run: yarn build:ts
             - save_cache:
                   key: repo-{{ .Environment.CIRCLE_SHA1 }}
                   paths:
@@ -40,7 +41,12 @@ jobs:
             - restore_cache:
                   keys:
                       - repo-{{ .Environment.CIRCLE_SHA1 }}
-            - run: yarn wsrun test:circleci contracts
+            - run: yarn wsrun test:circleci @0x/contracts-multisig
+            - run: yarn wsrun test:circleci @0x/contracts-utils
+            - run: yarn wsrun test:circleci @0x/contracts-libs
+            - run: yarn wsrun test:circleci @0x/contracts-tokens
+            - run: yarn wsrun test:circleci @0x/contracts-extensions
+            - run: yarn wsrun test:circleci @0x/contracts-protocol
     test-contracts-geth:
         docker:
             - image: circleci/node:9
@@ -52,7 +58,12 @@ jobs:
                       - repo-{{ .Environment.CIRCLE_SHA1 }}
             # HACK(albrow): we need to sleep 10 seconds to ensure the devnet is
             # initialized
-            - run: sleep 10 && TEST_PROVIDER=geth yarn wsrun test contracts
+            - run: sleep 10 && TEST_PROVIDER=geth yarn wsrun test @0x/contracts-multisig
+            - run: TEST_PROVIDER=geth yarn wsrun test @0x/contracts-utils
+            - run: TEST_PROVIDER=geth yarn wsrun test @0x/contracts-libs
+            - run: TEST_PROVIDER=geth yarn wsrun test @0x/contracts-tokens
+            - run: TEST_PROVIDER=geth yarn wsrun test @0x/contracts-extensions
+            - run: TEST_PROVIDER=geth yarn wsrun test @0x/contracts-protocol
     test-publish:
         resource_class: medium+
         docker:
@@ -73,6 +84,20 @@ jobs:
                   keys:
                       - repo-{{ .Environment.CIRCLE_SHA1 }}
             - run: yarn test:generate_docs:circleci
+    test-pipeline:
+        docker:
+            - image: circleci/node:9
+            - image: postgres:11-alpine
+        working_directory: ~/repo
+        steps:
+            - restore_cache:
+                  keys:
+                      - repo-{{ .Environment.CIRCLE_SHA1 }}
+            - run: ZEROEX_DATA_PIPELINE_TEST_DB_URL='postgresql://postgres@localhost/postgres' yarn wsrun test:circleci @0x/pipeline
+            - save_cache:
+                  key: coverage-pipeline-{{ .Environment.CIRCLE_SHA1 }}
+                  paths:
+                      - ~/repo/packages/pipeline/coverage/lcov.info
     test-rest:
         docker:
             - image: circleci/node:9
@@ -81,6 +106,7 @@ jobs:
             - restore_cache:
                   keys:
                       - repo-{{ .Environment.CIRCLE_SHA1 }}
+            - run: yarn wsrun test:circleci @0x/contracts-test-utils
             - run: yarn wsrun test:circleci @0x/abi-gen
             - run: yarn wsrun test:circleci @0x/assert
             - run: yarn wsrun test:circleci @0x/base-contract
@@ -165,6 +191,9 @@ jobs:
             - image: 0xorg/ganache-cli
               command: |
                   ganache-cli --gasLimit 10000000 --noVMErrorsOnRPCResponse --db /snapshot --noVMErrorsOnRPCResponse -p 8545 --networkId 50 -m "concert load couple harbor equip island argue ramp clarify fence smart topic"
+            - image: 0xorg/launch-kit-ci
+              command: |
+                  yarn start:ts -p 3000:3000
         steps:
             - checkout
             - run: sudo chown -R circleci:circleci /usr/local/bin
@@ -176,6 +205,11 @@ jobs:
                       cd python-packages/order_utils
                       python -m ensurepip
                       python -m pip install -e .[dev]
+            - run:
+                  command: |
+                      cd python-packages/sra_client
+                      python -m ensurepip
+                      python -m pip install -e .
             - save_cache:
                   key: deps9-{{ .Branch }}-{{ .Environment.CIRCLE_SHA1 }}
                   paths:
@@ -189,10 +223,18 @@ jobs:
                   command: |
                       cd python-packages/order_utils
                       coverage run setup.py test
+            - run:
+                  command: |
+                      cd python-packages/sra_client
+                      coverage run setup.py test
             - save_cache:
                   key: coverage-python-order-utils-{{ .Environment.CIRCLE_SHA1 }}
                   paths:
                       - ~/repo/python-packages/order_utils/.coverage
+            - save_cache:
+                  key: coverage-python-sra-client-{{ .Environment.CIRCLE_SHA1 }}
+                  paths:
+                      - ~/repo/python-packages/sra_client/.coverage
     test-rest-python:
         working_directory: ~/repo
         docker:
@@ -331,6 +373,9 @@ workflows:
             - test-contracts-geth:
                   requires:
                       - build
+            - test-pipeline:
+                  requires:
+                      - build
             - test-rest:
                   requires:
                       - build

.github/stale.yml

@@ -1,7 +1,7 @@
 # Number of days of inactivity before an issue becomes stale
 daysUntilStale: 30
 # Number of days of inactivity before a stale issue is closed
-daysUntilClose: 7
+daysUntilClose: 30
 # Issues with these labels will never be considered stale
 exemptLabels:
     - pinned

.gitignore

@@ -11,6 +11,10 @@ pids
 *.seed
 *.pid.lock
 
+# SQLite database files
+*.db
+*.sqlite
+
 # Directory for instrumented libs generated by jscoverage/JSCover
 lib-cov
 
@@ -79,13 +83,27 @@ packages/react-docs/example/public/bundle*
 packages/testnet-faucets/server/
 
 # generated contract artifacts/
-packages/contracts/generated-artifacts/
+contracts/protocol/generated-artifacts/
+contracts/multisig/generated-artifacts/
+contracts/utils/generated-artifacts/
+contracts/libs/generated-artifacts/
+contracts/interfaces/generated-artifacts/
+contracts/tokens/generated-artifacts/
+contracts/examples/generated-artifacts/
+contracts/extensions/generated-artifacts/
 packages/sol-cov/test/fixtures/artifacts/
 packages/metacoin/artifacts/
 
 # generated contract wrappers
 packages/abi-gen-wrappers/wrappers
-packages/contracts/generated-wrappers/
+contracts/protocol/generated-wrappers/
+contracts/multisig/generated-wrappers/
+contracts/utils/generated-wrappers/
+contracts/libs/generated-wrappers/
+contracts/interfaces/generated-wrappers/
+contracts/tokens/generated-wrappers/
+contracts/examples/generated-wrappers/
+contracts/extensions/generated-wrappers/
 packages/metacoin/src/contract_wrappers
 
 # solc-bin in sol-compiler

.prettierignore

@@ -1,7 +1,21 @@
 lib
 .nyc_output
-/packages/contracts/generated-wrappers
+/contracts/protocol/generated-wrappers
-/packages/contracts/generated-artifacts
+/contracts/protocol/generated-artifacts
+/contracts/multisig/generated-wrappers
+/contracts/multisig/generated-artifacts
+/contracts/utils/generated-wrappers
+/contracts/utils/generated-artifacts
+/contracts/libs/generated-wrappers
+/contracts/libs/generated-artifacts
+/contracts/interfaces/generated-wrappers
+/contracts/interfaces/generated-artifacts
+/contracts/tokens/generated-wrappers
+/contracts/tokens/generated-artifacts
+/contracts/examples/generated-wrappers
+/contracts/examples/generated-artifacts
+/contracts/extensions/generated-wrappers
+/contracts/extensions/generated-artifacts
 /packages/abi-gen-wrappers/src/generated-wrappers
 /packages/contract-artifacts/artifacts
 /python-packages/order_utils/src/zero_ex/contract_artifacts/artifacts

CODEOWNERS

@@ -14,7 +14,7 @@ packages/website/  @BMillman19 @fragosti @fabioberger @steveklebanoff
 packages/abi-gen/ @LogvinovLeon
 packages/base-contract/ @LogvinovLeon
 packages/connect/ @fragosti 
-packages/contract_templates/ @LogvinovLeon
+packages/abi-gen-templates/ @LogvinovLeon
 packages/contract-addresses/ @albrow
 packages/contract-artifacts/ @albrow
 packages/dev-utils/ @LogvinovLeon @fabioberger
@@ -32,4 +32,4 @@ packages/web3-wrapper/ @LogvinovLeon @fabioberger
 python-packages/ @feuGeneA
 
 # Protocol/smart contracts
-packages/contracts/test/ @albrow
+contracts/core/test/ @albrow

CONTRIBUTING.md

@@ -79,7 +79,20 @@ If using the Atom text editor, we recommend you install the following packages:
 *   VSCode: [prettier-vscode](https://marketplace.visualstudio.com/items?itemName=esbenp.prettier-vscode)
 *   Atom: [prettier-atom](https://atom.io/packages/prettier-atom)
 
-## Fix `submit-coverage` CI failure
+## Unenforced coding conventions
+
+A few of our coding conventions are not yet enforced by the linter/auto-formatter. Be careful to follow these conventions in your PR's.
+
+1.  Unused anonymous function parameters should be named with an underscore + number (e.g \_1, \_2, etc...)
+1.  There should be a new-line between methods in a class and between test cases.
+1.  If a string literal has the same value in two or more places, it should be a single constant referenced in both places.
+1.  Do not import from a project's `index.ts` (e.g import { Token } from '../src';). Always import from the source file itself.
+1.  Generic error variables should be named `err` instead of `e` or `error`.
+1.  If you _must_ cast a variable to any - try to type it back as fast as possible. (e.g., `const cw = ((zeroEx as any)._contractWrappers as ContractWrappers);`). This ensures subsequent code is type-safe.
+1.  Our enum conventions coincide with the recommended Typescript conventions, using capitalized keys, and all-caps snake-case values. Eg `GetStats = 'GET_STATS'`
+1.  All public, exported methods/functions/classes must have associated Javadoc-style comments.
+
+### Fix `submit-coverage` CI failure
 
 If you simply fork the repo and then create a PR from it, your PR will fail the `submit-coverage` check on CI. This is because the 0x CircleCI configuration sets the `COVERALLS_REPO_TOKEN` environment variable to the token for `0xProject/0x-monorepo`, but when running the check against your fork the token needs to match your repo's name `your-username/0x-monorepo`.
 

README.md

@@ -25,8 +25,9 @@ Visit our [developer portal](https://0xproject.com/docs/order-utils) for a compr
 ### Python Packages
 
 | Package                                          | Version                                                                                               | Description                                                                                       |
-| --------------------------------------------------- | ----------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------- |
+| ------------------------------------------------ | ----------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |
-| [`0x-order-utils.py`](/python-packages/order_utils) | [![PyPI](https://img.shields.io/pypi/v/0x-order-utils.svg)](https://pypi.org/project/0x-order-utils/) | A set of utilities for generating, parsing, signing and validating 0x orders |
+| [`0x-order-utils`](/python-packages/order_utils) | [![PyPI](https://img.shields.io/pypi/v/0x-order-utils.svg)](https://pypi.org/project/0x-order-utils/) | A set of utilities for generating, parsing, signing and validating 0x orders                      |
+| [`0x-sra-client`](/python-packages/sra_client)   | [![PyPI](https://img.shields.io/pypi/v/0x-sra-client.svg)](https://pypi.org/project/0x-sra-client/)   | A Python client for interacting with servers conforming to the Standard Relayer API specification |
 
 ### Typescript/Javascript Packages
 
@@ -77,8 +78,9 @@ Visit our [developer portal](https://0xproject.com/docs/order-utils) for a compr
 #### Private Packages
 
 | Package                                            | Description                                                                      |
-| -------------------------------------------------- | ---------------------------------------------------------------- |
+| -------------------------------------------------- | -------------------------------------------------------------------------------- |
-| [`@0x/contracts`](/packages/contracts)             | 0x protocol solidity smart contracts & tests                     |
+| [`@0x/contracts`](/contracts/core)                 | 0x protocol solidity smart contracts & tests                                     |
+| [`@0x/instant`](/packages/instant)                 | A free and flexible way to offer simple crypto purchasing in any app or website. |
 | [`@0x/testnet-faucets`](/packages/testnet-faucets) | A faucet micro-service that dispenses test ERC20 tokens or Ether                 |
 | [`@0x/website`](/packages/website)                 | 0x website                                                                       |
 

contracts/.solhint.json

@@ -5,6 +5,7 @@
         "avoid-tx-origin": "warn",
         "bracket-align": false,
         "code-complexity": false,
+        "compiler-fixed": false,
         "const-name-snakecase": "error",
         "expression-indent": "error",
         "function-max-lines": false,

contracts/TESTING.md

@@ -0,0 +1,48 @@
+# Contracts testing options
+
+## Revert stack traces
+
+If you want to see helpful stack traces (incl. line number, code snippet) for smart contract reverts, run the tests with:
+
+```
+yarn test:trace
+```
+
+**Note:** This currently slows down the test runs and is therefore not enabled by default.
+
+## Backing Ethereum node
+
+By default, our tests run against an in-process [Ganache](https://github.com/trufflesuite/ganache-core) instance. In order to run the tests against [Geth](https://github.com/ethereum/go-ethereum), first follow the instructions in the README for the devnet package to start the devnet Geth node. Then run:
+
+```bash
+TEST_PROVIDER=geth yarn test
+```
+
+## Code coverage
+
+In order to see the Solidity code coverage output generated by `@0x/sol-cov`, run:
+
+```
+yarn test:coverage
+```
+
+## Gas profiler
+
+In order to profile the gas costs for a specific smart contract call/transaction, you can run the tests in `profiler` mode.
+
+**Note:** Traces emitted by ganache have incorrect gas costs so we recommend using Geth for profiling.
+
+```
+TEST_PROVIDER=geth yarn test:profiler
+```
+
+You'll see a warning that you need to explicitly enable and disable the profiler before and after the block of code you want to profile.
+
+```typescript
+import { profiler } from './utils/profiler';
+profiler.start();
+// Some call to a smart contract
+profiler.stop();
+```
+
+Without explicitly starting and stopping the profiler, the profiler output will be too busy, and therefore unusable.

contracts/examples/CHANGELOG.json

@@ -0,0 +1,11 @@
+[
+    {
+        "timestamp": 1544741676,
+        "version": "1.0.2",
+        "changes": [
+            {
+                "note": "Dependencies updated"
+            }
+        ]
+    }
+]

contracts/examples/CHANGELOG.md

@@ -0,0 +1,10 @@
+<!--
+changelogUtils.file is auto-generated using the monorepo-scripts package. Don't edit directly.
+Edit the package's CHANGELOG.json file only.
+-->
+
+CHANGELOG
+
+## v1.0.2 - _December 13, 2018_
+
+    * Dependencies updated

contracts/examples/README.md

@@ -0,0 +1,56 @@
+## Contract examples
+
+Example smart contracts that interact with 0x protocol.
+
+## Usage
+
+Contracts can be found in the [contracts](./contracts) directory.
+This package contains example implementations of contracts that interact with the protocol but are _not_ intended for use in production. Examples include [filter](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#filter-contracts) contracts, a [Wallet](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#wallet) contract, and a [Validator](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#validator) contract, among others.
+
+## Contributing
+
+We strongly recommend that the community help us make improvements and determine the future direction of the protocol. To report bugs within this package, please create an issue in this repository.
+
+For proposals regarding the 0x protocol's smart contract architecture, message format, or additional functionality, go to the [0x Improvement Proposals (ZEIPs)](https://github.com/0xProject/ZEIPs) repository and follow the contribution guidelines provided therein.
+
+Please read our [contribution guidelines](../../CONTRIBUTING.md) before getting started.
+
+### Install Dependencies
+
+If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:
+
+```bash
+yarn config set workspaces-experimental true
+```
+
+Then install dependencies
+
+```bash
+yarn install
+```
+
+### Build
+
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
+
+```bash
+PKG=@0x/contracts-examples yarn build
+```
+
+Or continuously rebuild on change:
+
+```bash
+PKG=@0x/contracts-examples yarn watch
+```
+
+### Clean
+
+```bash
+yarn clean
+```
+
+### Lint
+
+```bash
+yarn lint
+```

contracts/examples/compiler.json

@@ -0,0 +1,22 @@
+{
+    "artifactsDir": "./generated-artifacts",
+    "contractsDir": "./contracts",
+    "compilerSettings": {
+        "optimizer": {
+            "enabled": true,
+            "runs": 1000000
+        },
+        "outputSelection": {
+            "*": {
+                "*": [
+                    "abi",
+                    "evm.bytecode.object",
+                    "evm.bytecode.sourceMap",
+                    "evm.deployedBytecode.object",
+                    "evm.deployedBytecode.sourceMap"
+                ]
+            }
+        }
+    },
+    "contracts": ["ExchangeWrapper", "Validator", "Wallet", "Whitelist"]
+}

contracts/examples/contracts/ExchangeWrapper/ExchangeWrapper.sol

@@ -19,8 +19,8 @@
 pragma solidity 0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../../protocol/Exchange/interfaces/IExchange.sol";
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
-import "../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
 
 
 contract ExchangeWrapper {

contracts/examples/contracts/Validator/Validator.sol

@@ -18,7 +18,7 @@
 
 pragma solidity 0.4.24;
 
-import "../../protocol/Exchange/interfaces/IValidator.sol";
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IValidator.sol";
 
 
 contract Validator is 

contracts/examples/contracts/Wallet/Wallet.sol

@@ -18,8 +18,8 @@
 
 pragma solidity 0.4.24;
 
-import "../../protocol/Exchange/interfaces/IWallet.sol";
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IWallet.sol";
-import "../../utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
 
 
 contract Wallet is 

contracts/examples/contracts/Whitelist/Whitelist.sol

@@ -19,9 +19,9 @@
 pragma solidity 0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../../protocol/Exchange/interfaces/IExchange.sol";
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
-import "../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../../utils/Ownable/Ownable.sol";
+import "@0x/contracts-utils/contracts/utils/Ownable/Ownable.sol";
 
 
 contract Whitelist is

contracts/examples/package.json

@@ -0,0 +1,83 @@
+{
+    "name": "@0x/contracts-examples",
+    "version": "1.0.2",
+    "engines": {
+        "node": ">=6.12"
+    },
+    "description": "Smart contract examples of 0x protocol",
+    "main": "lib/src/index.js",
+    "directories": {
+        "test": "test"
+    },
+    "scripts": {
+        "build": "yarn pre_build && tsc -b",
+        "build:ci": "yarn build",
+        "pre_build": "run-s compile generate_contract_wrappers",
+        "compile": "sol-compiler",
+        "watch": "sol-compiler -w",
+        "clean": "shx rm -rf lib generated-artifacts generated-wrappers",
+        "generate_contract_wrappers": "abi-gen --abis  ${npm_package_config_abis} --template ../../node_modules/@0x/abi-gen-templates/contract.handlebars --partials '../../node_modules/@0x/abi-gen-templates/partials/**/*.handlebars' --output generated-wrappers --backend ethers",
+        "lint": "tslint --format stylish --project . --exclude ./generated-wrappers/**/* --exclude ./generated-artifacts/**/* --exclude **/lib/**/* && yarn lint-contracts",
+        "lint-contracts": "solhint -c ../.solhint.json contracts/**/**/**/**/*.sol"
+    },
+    "config": {
+        "abis": "generated-artifacts/@(ExchangeWrapper|Validator|Wallet|Whitelist).json"
+    },
+    "repository": {
+        "type": "git",
+        "url": "https://github.com/0xProject/0x-monorepo.git"
+    },
+    "license": "Apache-2.0",
+    "bugs": {
+        "url": "https://github.com/0xProject/0x-monorepo/issues"
+    },
+    "homepage": "https://github.com/0xProject/0x-monorepo/contracts/examples/README.md",
+    "devDependencies": {
+        "@0x/abi-gen": "^1.0.19",
+        "@0x/contracts-test-utils": "^1.0.2",
+        "@0x/dev-utils": "^1.0.21",
+        "@0x/sol-compiler": "^1.1.16",
+        "@0x/sol-cov": "^2.1.16",
+        "@0x/subproviders": "^2.1.8",
+        "@0x/tslint-config": "^2.0.0",
+        "@types/bn.js": "^4.11.0",
+        "@types/lodash": "4.14.104",
+        "@types/node": "*",
+        "@types/yargs": "^10.0.0",
+        "chai": "^4.0.1",
+        "chai-as-promised": "^7.1.0",
+        "chai-bignumber": "^2.0.1",
+        "dirty-chai": "^2.0.1",
+        "ethereumjs-abi": "0.6.5",
+        "make-promises-safe": "^1.1.0",
+        "mocha": "^4.1.0",
+        "npm-run-all": "^4.1.2",
+        "shx": "^0.2.2",
+        "solc": "^0.4.24",
+        "solhint": "^1.4.1",
+        "tslint": "5.11.0",
+        "typescript": "3.0.1",
+        "yargs": "^10.0.3"
+    },
+    "dependencies": {
+        "@0x/base-contract": "^3.0.10",
+        "@0x/contracts-interfaces": "^1.0.2",
+        "@0x/contracts-libs": "^1.0.2",
+        "@0x/contracts-multisig": "^1.0.2",
+        "@0x/contracts-tokens": "^1.0.2",
+        "@0x/contracts-utils": "^1.0.2",
+        "@0x/order-utils": "^3.0.7",
+        "@0x/types": "^1.4.1",
+        "@0x/typescript-typings": "^3.0.6",
+        "@0x/utils": "^2.0.8",
+        "@0x/web3-wrapper": "^3.2.1",
+        "@types/js-combinatorics": "^0.5.29",
+        "bn.js": "^4.11.8",
+        "ethereum-types": "^1.1.4",
+        "ethereumjs-util": "^5.1.1",
+        "lodash": "^4.17.5"
+    },
+    "publishConfig": {
+        "access": "public"
+    }
+}

contracts/examples/src/artifacts/index.ts

@@ -0,0 +1,13 @@
+import { ContractArtifact } from 'ethereum-types';
+
+import * as ExchangeWrapper from '../../generated-artifacts/ExchangeWrapper.json';
+import * as Validator from '../../generated-artifacts/Validator.json';
+import * as Wallet from '../../generated-artifacts/Wallet.json';
+import * as Whitelist from '../../generated-artifacts/Whitelist.json';
+
+export const artifacts = {
+    ExchangeWrapper: ExchangeWrapper as ContractArtifact,
+    Validator: Validator as ContractArtifact,
+    Wallet: Wallet as ContractArtifact,
+    Whitelist: Whitelist as ContractArtifact,
+};

contracts/examples/src/index.ts

@@ -0,0 +1,2 @@
+export * from './artifacts';
+export * from './wrappers';

contracts/examples/src/wrappers/index.ts

@@ -0,0 +1,4 @@
+export * from '../../generated-wrappers/exchange_wrapper';
+export * from '../../generated-wrappers/validator';
+export * from '../../generated-wrappers/wallet';
+export * from '../../generated-wrappers/whitelist';

contracts/examples/tsconfig.json

@@ -0,0 +1,16 @@
+{
+    "extends": "../../tsconfig",
+    "compilerOptions": {
+        "outDir": "lib",
+        "rootDir": ".",
+        "resolveJsonModule": true
+    },
+    "include": ["./src/**/*", "./test/**/*", "./generated-wrappers/**/*"],
+    "files": [
+        "./generated-artifacts/ExchangeWrapper.json",
+        "./generated-artifacts/Validator.json",
+        "./generated-artifacts/Wallet.json",
+        "./generated-artifacts/Whitelist.json"
+    ],
+    "exclude": ["./deploy/solc/solc_bin"]
+}

contracts/extensions/CHANGELOG.json

@@ -0,0 +1,28 @@
+[
+    {
+        "version": "1.1.0",
+        "changes": [
+            {
+                "note": "Added Balance Threshold Filter",
+                "pr": 1383
+            },
+            {
+                "note": "Add OrderMatcher",
+                "pr": 1117
+            },
+            {
+                "note": "Add OrderValidator",
+                "pr": 1464
+            }
+        ]
+    },
+    {
+        "timestamp": 1544741676,
+        "version": "1.0.2",
+        "changes": [
+            {
+                "note": "Dependencies updated"
+            }
+        ]
+    }
+]

contracts/extensions/CHANGELOG.md

@@ -0,0 +1,10 @@
+<!--
+changelogUtils.file is auto-generated using the monorepo-scripts package. Don't edit directly.
+Edit the package's CHANGELOG.json file only.
+-->
+
+CHANGELOG
+
+## v1.0.2 - _December 13, 2018_
+
+    * Dependencies updated

contracts/extensions/DEPLOYS.json

@@ -0,0 +1,31 @@
+[
+    {
+        "name": "Forwarder",
+        "version": "1.1.0",
+        "changes": [
+            {
+                "note": "Round up when calculating remaining amounts in marketBuy functions",
+                "pr": 1162,
+                "networks": {
+                    "1": "0x5468a1dc173652ee28d249c271fa9933144746b1",
+                    "3": "0x2240dab907db71e64d3e0dba4800c83b5c502d4e",
+                    "42": "0x17992e4ffb22730138e4b62aaa6367fa9d3699a6"
+                }
+            }
+        ]
+    },
+    {
+        "name": "Forwarder",
+        "version": "1.0.0",
+        "changes": [
+            {
+                "note": "protocol v2 deploy",
+                "networks": {
+                    "1": "0x7afc2d5107af94c462a194d2c21b5bdd238709d6",
+                    "3": "0x3983e204b12b3c02fb0638caf2cd406a62e0ead3",
+                    "42": "0xd85e2fa7e7e252b27b01bf0d65c946959d2f45b8"
+                }
+            }
+        ]
+    }
+]

contracts/extensions/README.md

@@ -0,0 +1,69 @@
+## Contract extensions
+
+Smart contracts that implement extensions for the 0x protocol.
+
+## Usage
+
+Contract extensions of the protocol can be found in the [contracts](./contracts) directory. This directory contains contracts that interact with the 2.0.0 contracts and will be used in production, such as the [Forwarder](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/forwarder-specification.md) contract.
+
+## Bug bounty
+
+A bug bounty for the 2.0.0 contracts is ongoing! Instructions can be found [here](https://0xproject.com/wiki#Bug-Bounty).
+
+## Contributing
+
+We strongly recommend that the community help us make improvements and determine the future direction of the protocol. To report bugs within this package, please create an issue in this repository.
+
+For proposals regarding the 0x protocol's smart contract architecture, message format, or additional functionality, go to the [0x Improvement Proposals (ZEIPs)](https://github.com/0xProject/ZEIPs) repository and follow the contribution guidelines provided therein.
+
+Please read our [contribution guidelines](../../CONTRIBUTING.md) before getting started.
+
+### Install Dependencies
+
+If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:
+
+```bash
+yarn config set workspaces-experimental true
+```
+
+Then install dependencies
+
+```bash
+yarn install
+```
+
+### Build
+
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
+
+```bash
+PKG=@0x/contracts-extensions yarn build
+```
+
+Or continuously rebuild on change:
+
+```bash
+PKG=@0x/contracts-extensions yarn watch
+```
+
+### Clean
+
+```bash
+yarn clean
+```
+
+### Lint
+
+```bash
+yarn lint
+```
+
+### Run Tests
+
+```bash
+yarn test
+```
+
+#### Testing options
+
+Contracts testing options like coverage, profiling, revert traces or backing node choosing - are described [here](../TESTING.md).

contracts/extensions/compiler.json

@@ -0,0 +1,22 @@
+{
+    "artifactsDir": "./generated-artifacts",
+    "contractsDir": "./contracts",
+    "compilerSettings": {
+        "optimizer": {
+            "enabled": true,
+            "runs": 1000000
+        },
+        "outputSelection": {
+            "*": {
+                "*": [
+                    "abi",
+                    "evm.bytecode.object",
+                    "evm.bytecode.sourceMap",
+                    "evm.deployedBytecode.object",
+                    "evm.deployedBytecode.sourceMap"
+                ]
+            }
+        }
+    },
+    "contracts": ["BalanceThresholdFilter", "DutchAuction", "Forwarder", "OrderMatcher", "OrderValidator"]
+}

contracts/extensions/contracts/BalanceThresholdFilter/BalanceThresholdFilter.sol

@@ -0,0 +1,45 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity 0.4.24;
+
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
+import "./interfaces/IThresholdAsset.sol";
+import "./MixinBalanceThresholdFilterCore.sol";
+
+
+contract BalanceThresholdFilter is
+    MixinBalanceThresholdFilterCore
+{
+
+    /// @dev Constructs BalanceThresholdFilter.
+    /// @param exchange Address of 0x exchange.
+    /// @param thresholdAsset The asset that must be held by makers/takers.
+    /// @param balanceThreshold The minimum balance of `thresholdAsset` that must be held by makers/takers.
+    constructor(
+        address exchange,
+        address thresholdAsset,
+        uint256 balanceThreshold
+    )
+        public
+    {
+        EXCHANGE = IExchange(exchange);
+        THRESHOLD_ASSET = IThresholdAsset(thresholdAsset);
+        BALANCE_THRESHOLD = balanceThreshold;
+    }
+}

contracts/extensions/contracts/BalanceThresholdFilter/MixinBalanceThresholdFilterCore.sol

@@ -0,0 +1,135 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "@0x/contracts-libs/contracts/libs/LibExchangeSelectors.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
+import "./mixins/MBalanceThresholdFilterCore.sol";
+import "./MixinExchangeCalldata.sol";
+
+
+contract MixinBalanceThresholdFilterCore is
+    MBalanceThresholdFilterCore,
+    MixinExchangeCalldata,
+    LibOrder,
+    LibExchangeSelectors
+{
+
+    /// @dev Executes an Exchange transaction iff the maker and taker meet 
+    ///      the hold at least `BALANCE_THRESHOLD` of the asset `THRESHOLD_ASSET` OR 
+    ///      the exchange function is a cancellation.
+    ///      Supported Exchange functions:
+    ///          batchFillOrders
+    ///          batchFillOrdersNoThrow
+    ///          batchFillOrKillOrders
+    ///          fillOrder
+    ///          fillOrderNoThrow
+    ///          fillOrKillOrder
+    ///          marketBuyOrders
+    ///          marketBuyOrdersNoThrow
+    ///          marketSellOrders
+    ///          marketSellOrdersNoThrow
+    ///          matchOrders
+    ///          cancelOrder
+    ///          batchCancelOrders
+    ///          cancelOrdersUpTo
+    ///     Trying to call any other exchange function will throw.
+    /// @param salt Arbitrary number to ensure uniqueness of transaction hash.
+    /// @param signerAddress Address of transaction signer.
+    /// @param signedExchangeTransaction AbiV2 encoded calldata.
+    /// @param signature Proof of signer transaction by signer.
+    function executeTransaction(
+        uint256 salt,
+        address signerAddress,
+        bytes signedExchangeTransaction,
+        bytes signature
+    ) 
+        external
+    {
+        // Get accounts whose balances must be validated
+        address[] memory addressesToValidate = getAddressesToValidate(signerAddress);
+
+        // Validate account balances
+        uint256 balanceThreshold = BALANCE_THRESHOLD;
+        IThresholdAsset thresholdAsset = THRESHOLD_ASSET;
+        for (uint256 i = 0; i < addressesToValidate.length; ++i) {
+            uint256 addressBalance = thresholdAsset.balanceOf(addressesToValidate[i]);
+            require(
+                addressBalance >= balanceThreshold,
+                "AT_LEAST_ONE_ADDRESS_DOES_NOT_MEET_BALANCE_THRESHOLD"
+            );
+        }
+        emit ValidatedAddresses(addressesToValidate);
+        
+        // All addresses are valid. Execute exchange function.
+        EXCHANGE.executeTransaction(
+            salt,
+            signerAddress,
+            signedExchangeTransaction,
+            signature
+        );
+    }
+
+    /// @dev Constructs an array of addresses to be validated.
+    ///      Addresses depend on which Exchange function is to be called
+    ///      (defined by `signedExchangeTransaction` above).
+    /// @param signerAddress Address of transaction signer.
+    /// @return addressesToValidate Array of addresses to validate.
+    function getAddressesToValidate(address signerAddress)
+        internal pure
+        returns (address[] memory addressesToValidate)
+    {
+        bytes4 exchangeFunctionSelector = bytes4(exchangeCalldataload(0));
+        // solhint-disable expression-indent
+        if (
+            exchangeFunctionSelector == BATCH_FILL_ORDERS_SELECTOR              ||
+            exchangeFunctionSelector == BATCH_FILL_ORDERS_NO_THROW_SELECTOR     ||
+            exchangeFunctionSelector == BATCH_FILL_OR_KILL_ORDERS_SELECTOR      ||
+            exchangeFunctionSelector == MARKET_BUY_ORDERS_SELECTOR              ||
+            exchangeFunctionSelector == MARKET_BUY_ORDERS_NO_THROW_SELECTOR     ||
+            exchangeFunctionSelector == MARKET_SELL_ORDERS_SELECTOR             ||
+            exchangeFunctionSelector == MARKET_SELL_ORDERS_NO_THROW_SELECTOR
+        ) {
+            addressesToValidate = loadMakerAddressesFromOrderArray(0);
+            addressesToValidate = addressesToValidate.append(signerAddress);
+        } else if (
+            exchangeFunctionSelector == FILL_ORDER_SELECTOR             ||
+            exchangeFunctionSelector == FILL_ORDER_NO_THROW_SELECTOR    ||
+            exchangeFunctionSelector == FILL_OR_KILL_ORDER_SELECTOR
+        ) {
+            address makerAddress = loadMakerAddressFromOrder(0);
+            addressesToValidate = addressesToValidate.append(makerAddress);
+            addressesToValidate = addressesToValidate.append(signerAddress);
+        } else if (exchangeFunctionSelector == MATCH_ORDERS_SELECTOR) {
+            address leftMakerAddress = loadMakerAddressFromOrder(0);
+            addressesToValidate = addressesToValidate.append(leftMakerAddress);
+            address rightMakerAddress = loadMakerAddressFromOrder(1);
+            addressesToValidate = addressesToValidate.append(rightMakerAddress);
+            addressesToValidate = addressesToValidate.append(signerAddress);
+        } else if (
+            exchangeFunctionSelector != CANCEL_ORDER_SELECTOR           &&
+            exchangeFunctionSelector != BATCH_CANCEL_ORDERS_SELECTOR    &&
+            exchangeFunctionSelector != CANCEL_ORDERS_UP_TO_SELECTOR
+        ) {
+            revert("INVALID_OR_BLOCKED_EXCHANGE_SELECTOR");
+        }
+        // solhint-enable expression-indent
+        return addressesToValidate;
+    }
+}

contracts/extensions/contracts/BalanceThresholdFilter/MixinExchangeCalldata.sol

@@ -0,0 +1,103 @@
+    
+    /*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "./mixins/MExchangeCalldata.sol";
+import "@0x/contracts-libs/contracts/libs/LibAddressArray.sol";
+
+
+contract MixinExchangeCalldata is 
+    MExchangeCalldata
+{
+
+    using LibAddressArray for address[];
+
+    /// @dev Emulates the `calldataload` opcode on the embedded Exchange calldata,
+    ///      which is accessed through `signedExchangeTransaction`.
+    /// @param offset  Offset into the Exchange calldata.
+    /// @return value  Corresponding 32 byte value stored at `offset`.
+    function exchangeCalldataload(uint256 offset)
+        internal pure
+        returns (bytes32 value)
+    {
+        assembly {
+            // Pointer to exchange transaction
+            // 0x04 for calldata selector
+            // 0x40 to access `signedExchangeTransaction`, which is the third parameter
+            let exchangeTxPtr := calldataload(0x44)
+
+            // Offset into Exchange calldata
+            // We compute this by adding 0x24 to the `exchangeTxPtr` computed above.
+            // 0x04 for calldata selector
+            // 0x20 for length field of `signedExchangeTransaction`
+            let exchangeCalldataOffset := add(exchangeTxPtr, add(0x24, offset))
+            value := calldataload(exchangeCalldataOffset)
+        }
+        return value;
+    }
+
+    /// @dev Convenience function that skips the 4 byte selector when loading
+    ///      from the embedded Exchange calldata.
+    /// @param offset  Offset into the Exchange calldata (minus the 4 byte selector)
+    /// @return value  Corresponding 32 byte value stored at `offset` + 4.
+    function loadExchangeData(uint256 offset)
+        internal pure
+        returns (bytes32 value)
+    {
+        value = exchangeCalldataload(offset + 4);
+        return value;
+    }
+
+    /// @dev Extracts the maker address from an order stored in the Exchange calldata
+    ///      (which is embedded in `signedExchangeTransaction`).
+    /// @param orderParamIndex  Index of the order in the Exchange function's signature.
+    /// @return makerAddress The extracted maker address.
+    function loadMakerAddressFromOrder(uint256 orderParamIndex)
+        internal pure
+        returns (address makerAddress)
+    {
+        uint256 orderOffsetInBytes = orderParamIndex * 32;
+        uint256 orderPtr = uint256(loadExchangeData(orderOffsetInBytes));
+        makerAddress = address(loadExchangeData(orderPtr));
+        return makerAddress;
+    }
+
+    /// @dev Extracts the maker addresses from an array of orders stored in the Exchange calldata
+    ///      (which is embedded in `signedExchangeTransaction`).
+    /// @param orderArrayParamIndex  Index of the order array in the Exchange function's signature
+    /// @return makerAddresses The extracted maker addresses.
+    function loadMakerAddressesFromOrderArray(uint256 orderArrayParamIndex)
+        internal pure
+        returns (address[] makerAddresses)
+    {
+        uint256 orderArrayOffsetInBytes = orderArrayParamIndex * 32;
+        uint256 orderArrayPtr = uint256(loadExchangeData(orderArrayOffsetInBytes));
+        uint256 orderArrayLength = uint256(loadExchangeData(orderArrayPtr));
+        uint256 orderArrayLengthInBytes = orderArrayLength * 32;
+        uint256 orderArrayElementPtr = orderArrayPtr + 32;
+        uint256 orderArrayElementEndPtr = orderArrayElementPtr + orderArrayLengthInBytes;
+        for (uint orderPtrOffset = orderArrayElementPtr; orderPtrOffset < orderArrayElementEndPtr; orderPtrOffset += 32) {
+            uint256 orderPtr = uint256(loadExchangeData(orderPtrOffset));
+            address makerAddress = address(loadExchangeData(orderPtr + orderArrayElementPtr));
+            makerAddresses = makerAddresses.append(makerAddress);
+        }
+        return makerAddresses;
+    }
+}

contracts/extensions/contracts/BalanceThresholdFilter/interfaces/IBalanceThresholdFilterCore.sol

@@ -0,0 +1,55 @@
+
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+
+contract IBalanceThresholdFilterCore {
+    
+    /// @dev Executes an Exchange transaction iff the maker and taker meet 
+    ///      the hold at least `BALANCE_THRESHOLD` of the asset `THRESHOLD_ASSET` OR 
+    ///      the exchange function is a cancellation.
+    ///      Supported Exchange functions:
+    ///         - batchFillOrders
+    ///         - batchFillOrdersNoThrow
+    ///         - batchFillOrKillOrders
+    ///         - fillOrder
+    ///         - fillOrderNoThrow
+    ///         - fillOrKillOrder
+    ///         - marketBuyOrders
+    ///         - marketBuyOrdersNoThrow
+    ///         - marketSellOrders
+    ///         - marketSellOrdersNoThrow
+    ///         - matchOrders
+    ///         - cancelOrder
+    ///         - batchCancelOrders
+    ///         - cancelOrdersUpTo
+    ///     Trying to call any other exchange function will throw.
+    /// @param salt Arbitrary number to ensure uniqueness of transaction hash.
+    /// @param signerAddress Address of transaction signer.
+    /// @param signedExchangeTransaction AbiV2 encoded calldata.
+    /// @param signature Proof of signer transaction by signer.
+    function executeTransaction(
+        uint256 salt,
+        address signerAddress,
+        bytes signedExchangeTransaction,
+        bytes signature
+    ) 
+        external;
+}

contracts/extensions/contracts/BalanceThresholdFilter/interfaces/IThresholdAsset.sol

@@ -0,0 +1,31 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+
+contract IThresholdAsset {
+
+    /// @param _owner The address from which the balance will be retrieved
+    /// @return Balance of owner
+    function balanceOf(address _owner)
+        external
+        view
+        returns (uint256);
+
+}

contracts/extensions/contracts/BalanceThresholdFilter/mixins/MBalanceThresholdFilterCore.sol

@@ -0,0 +1,54 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
+import "../interfaces/IThresholdAsset.sol";
+import "../interfaces/IBalanceThresholdFilterCore.sol";
+
+
+contract MBalanceThresholdFilterCore is
+    IBalanceThresholdFilterCore
+{
+
+    // Points to 0x exchange contract
+    // solhint-disable var-name-mixedcase
+    IExchange internal EXCHANGE;
+
+    // The asset that must be held by makers/takers
+    IThresholdAsset internal THRESHOLD_ASSET;
+
+    // The minimum balance of `THRESHOLD_ASSET` that must be held by makers/takers
+    uint256 internal BALANCE_THRESHOLD;
+    // solhint-enable var-name-mixedcase
+
+    // Addresses that hold at least `BALANCE_THRESHOLD` of `THRESHOLD_ASSET`
+    event ValidatedAddresses (
+        address[] addresses
+    );
+
+    /// @dev Constructs an array of addresses to be validated.
+    ///      Addresses depend on which Exchange function is to be called
+    ///      (defined by `signedExchangeTransaction` above).
+    /// @param signerAddress Address of transaction signer.
+    /// @return addressesToValidate Array of addresses to validate.
+    function getAddressesToValidate(address signerAddress)
+        internal pure
+        returns (address[] memory addressesToValidate);
+}

contracts/extensions/contracts/BalanceThresholdFilter/mixins/MExchangeCalldata.sol

@@ -0,0 +1,56 @@
+    
+    /*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+
+contract MExchangeCalldata {
+
+    /// @dev Emulates the `calldataload` opcode on the embedded Exchange calldata,
+    ///      which is accessed through `signedExchangeTransaction`.
+    /// @param offset  Offset into the Exchange calldata.
+    /// @return value  Corresponding 32 byte value stored at `offset`.
+    function exchangeCalldataload(uint256 offset)
+        internal pure
+        returns (bytes32 value);
+
+    /// @dev Convenience function that skips the 4 byte selector when loading
+    ///      from the embedded Exchange calldata.
+    /// @param offset  Offset into the Exchange calldata (minus the 4 byte selector)
+    /// @return value  Corresponding 32 byte value stored at `offset` + 4.
+    function loadExchangeData(uint256 offset)
+        internal pure
+        returns (bytes32 value);
+
+    /// @dev Extracts the maker address from an order stored in the Exchange calldata
+    ///      (which is embedded in `signedExchangeTransaction`).
+    /// @param orderParamIndex  Index of the order in the Exchange function's signature.
+    /// @return makerAddress The extracted maker address.
+    function loadMakerAddressFromOrder(uint256 orderParamIndex)
+        internal pure
+        returns (address makerAddress);
+
+    /// @dev Extracts the maker addresses from an array of orders stored in the Exchange calldata
+    ///      (which is embedded in `signedExchangeTransaction`).
+    /// @param orderArrayParamIndex  Index of the order array in the Exchange function's signature
+    /// @return makerAddresses The extracted maker addresses.
+    function loadMakerAddressesFromOrderArray(uint256 orderArrayParamIndex)
+        internal pure
+        returns (address[] makerAddresses);
+}

contracts/extensions/contracts/DutchAuction/DutchAuction.sol

@@ -0,0 +1,205 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity 0.4.24;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC20Token/IERC20Token.sol";
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/SafeMath/SafeMath.sol";
+
+
+contract DutchAuction is
+    SafeMath
+{
+    using LibBytes for bytes;
+
+    // solhint-disable var-name-mixedcase
+    IExchange internal EXCHANGE;
+
+    struct AuctionDetails {
+        uint256 beginTimeSeconds;    // Auction begin unix timestamp: sellOrder.makerAssetData
+        uint256 endTimeSeconds;      // Auction end unix timestamp: sellOrder.expiryTimeSeconds
+        uint256 beginAmount;         // Auction begin amount: sellOrder.makerAssetData
+        uint256 endAmount;           // Auction end amount: sellOrder.takerAssetAmount
+        uint256 currentAmount;       // Calculated amount given block.timestamp
+        uint256 currentTimeSeconds;  // block.timestamp
+    }
+
+    constructor (address _exchange)
+        public
+    {
+        EXCHANGE = IExchange(_exchange);
+    }
+
+    /// @dev Matches the buy and sell orders at an amount given the following: the current block time, the auction
+    ///      start time and the auction begin amount. The sell order is a an order at the lowest amount
+    ///      at the end of the auction. Excess from the match is transferred to the seller.
+    ///      Over time the price moves from beginAmount to endAmount given the current block.timestamp.
+    ///      sellOrder.expiryTimeSeconds is the end time of the auction.
+    ///      sellOrder.takerAssetAmount is the end amount of the auction (lowest possible amount).
+    ///      sellOrder.makerAssetData is the ABI encoded Asset Proxy data with the following data appended
+    ///      buyOrder.makerAssetData is the buyers bid on the auction, must meet the amount for the current block timestamp
+    ///      (uint256 beginTimeSeconds, uint256 beginAmount).
+    ///      This function reverts in the following scenarios:
+    ///         * Auction has not started (auctionDetails.currentTimeSeconds < auctionDetails.beginTimeSeconds)
+    ///         * Auction has expired (auctionDetails.endTimeSeconds < auctionDetails.currentTimeSeconds)
+    ///         * Amount is invalid: Buy order amount is too low (buyOrder.makerAssetAmount < auctionDetails.currentAmount)
+    ///         * Amount is invalid: Invalid begin amount (auctionDetails.beginAmount > auctionDetails.endAmount)
+    ///         * Any failure in the 0x Match Orders
+    /// @param buyOrder The Buyer's order. This order is for the current expected price of the auction.
+    /// @param sellOrder The Seller's order. This order is for the lowest amount (at the end of the auction).
+    /// @param buySignature Proof that order was created by the buyer.
+    /// @param sellSignature Proof that order was created by the seller.
+    /// @return matchedFillResults amounts filled and fees paid by maker and taker of matched orders.
+    function matchOrders(
+        LibOrder.Order memory buyOrder,
+        LibOrder.Order memory sellOrder,
+        bytes memory buySignature,
+        bytes memory sellSignature
+    )
+        public
+        returns (LibFillResults.MatchedFillResults memory matchedFillResults)
+    {
+        AuctionDetails memory auctionDetails = getAuctionDetails(sellOrder);
+        // Ensure the auction has not yet started
+        require(
+            auctionDetails.currentTimeSeconds >= auctionDetails.beginTimeSeconds,
+            "AUCTION_NOT_STARTED"
+        );
+        // Ensure the auction has not expired. This will fail later in 0x but we can save gas by failing early
+        require(
+            sellOrder.expirationTimeSeconds > auctionDetails.currentTimeSeconds,
+            "AUCTION_EXPIRED"
+        );
+        // Validate the buyer amount is greater than the current auction amount
+        require(
+            buyOrder.makerAssetAmount >= auctionDetails.currentAmount,
+            "INVALID_AMOUNT"
+        );
+        // Match orders, maximally filling `buyOrder`
+        matchedFillResults = EXCHANGE.matchOrders(
+            buyOrder,
+            sellOrder,
+            buySignature,
+            sellSignature
+        );
+        // The difference in sellOrder.takerAssetAmount and current amount is given as spread to the matcher
+        // This may include additional spread from the buyOrder.makerAssetAmount and the currentAmount.
+        // e.g currentAmount is 30, sellOrder.takerAssetAmount is 10 and buyOrder.makerAssetamount is 40.
+        // 10 (40-30) is returned to the buyer, 20 (30-10) sent to the seller and 10 has previously
+        // been transferred to the seller during matchOrders
+        uint256 leftMakerAssetSpreadAmount = matchedFillResults.leftMakerAssetSpreadAmount;
+        if (leftMakerAssetSpreadAmount > 0) {
+            // ERC20 Asset data itself is encoded as follows:
+            //
+            // | Area     | Offset | Length  | Contents                            |
+            // |----------|--------|---------|-------------------------------------|
+            // | Header   | 0      | 4       | function selector                   |
+            // | Params   |        | 1 * 32  | function parameters:                |
+            // |          | 4      | 12      |   1. token address padding          |
+            // |          | 16     | 20      |   2. token address                  |
+            bytes memory assetData = sellOrder.takerAssetData;
+            address token = assetData.readAddress(16);
+            // Calculate the excess from the buy order. This can occur if the buyer sends in a higher
+            // amount than the calculated current amount
+            uint256 buyerExcessAmount = safeSub(buyOrder.makerAssetAmount, auctionDetails.currentAmount);
+            uint256 sellerExcessAmount = safeSub(leftMakerAssetSpreadAmount, buyerExcessAmount);
+            // Return the difference between auctionDetails.currentAmount and sellOrder.takerAssetAmount
+            // to the seller
+            if (sellerExcessAmount > 0) {
+                IERC20Token(token).transfer(sellOrder.makerAddress, sellerExcessAmount);
+            }
+            // Return the difference between buyOrder.makerAssetAmount and auctionDetails.currentAmount
+            // to the buyer
+            if (buyerExcessAmount > 0) {
+                IERC20Token(token).transfer(buyOrder.makerAddress, buyerExcessAmount);
+            }
+        }
+        return matchedFillResults;
+    }
+
+    /// @dev Calculates the Auction Details for the given order
+    /// @param order The sell order
+    /// @return AuctionDetails
+    function getAuctionDetails(
+        LibOrder.Order memory order
+    )
+        public
+        returns (AuctionDetails memory auctionDetails)
+    {
+        uint256 makerAssetDataLength = order.makerAssetData.length;
+        // It is unknown the encoded data of makerAssetData, we assume the last 64 bytes
+        // are the Auction Details encoding.
+        // Auction Details is encoded as follows:
+        //
+        // | Area     | Offset | Length  | Contents                            |
+        // |----------|--------|---------|-------------------------------------|
+        // | Params   |        | 2 * 32  | parameters:                         |
+        // |          | -64    | 32      |   1. auction begin unix timestamp   |
+        // |          | -32    | 32      |   2. auction begin begin amount     |
+        // ERC20 asset data length is 4+32, 64 for auction details results in min length 100
+        require(
+            makerAssetDataLength >= 100,
+            "INVALID_ASSET_DATA"
+        );
+        uint256 auctionBeginTimeSeconds = order.makerAssetData.readUint256(makerAssetDataLength - 64);
+        uint256 auctionBeginAmount = order.makerAssetData.readUint256(makerAssetDataLength - 32);
+        // Ensure the auction has a valid begin time
+        require(
+            order.expirationTimeSeconds > auctionBeginTimeSeconds,
+            "INVALID_BEGIN_TIME"
+        );
+        uint256 auctionDurationSeconds = order.expirationTimeSeconds-auctionBeginTimeSeconds;
+        // Ensure the auction goes from high to low
+        uint256 minAmount = order.takerAssetAmount;
+        require(
+            auctionBeginAmount > minAmount,
+            "INVALID_AMOUNT"
+        );
+        uint256 amountDelta = auctionBeginAmount-minAmount;
+        // solhint-disable-next-line not-rely-on-time
+        uint256 timestamp = block.timestamp;
+        auctionDetails.beginTimeSeconds = auctionBeginTimeSeconds;
+        auctionDetails.endTimeSeconds = order.expirationTimeSeconds;
+        auctionDetails.beginAmount = auctionBeginAmount;
+        auctionDetails.endAmount = minAmount;
+        auctionDetails.currentTimeSeconds = timestamp;
+
+        uint256 remainingDurationSeconds = order.expirationTimeSeconds-timestamp;
+        if (timestamp < auctionBeginTimeSeconds) {
+            // If the auction has not yet begun the current amount is the auctionBeginAmount
+            auctionDetails.currentAmount = auctionBeginAmount;
+        } else if (timestamp >= order.expirationTimeSeconds) {
+            // If the auction has ended the current amount is the minAmount.
+            // Auction end time is guaranteed by 0x Exchange due to the order expiration
+            auctionDetails.currentAmount = minAmount;
+        } else {
+            auctionDetails.currentAmount = safeAdd(
+                minAmount,
+                safeDiv(
+                    safeMul(remainingDurationSeconds, amountDelta),
+                    auctionDurationSeconds
+                )
+            );
+        }
+        return auctionDetails;
+    }
+}

contracts/extensions/contracts/Forwarder/MixinAssets.sol

@@ -16,12 +16,12 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
-import "../../utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
-import "../../utils/Ownable/Ownable.sol";
+import "@0x/contracts-utils/contracts/utils/Ownable/Ownable.sol";
-import "../../tokens/ERC20Token/IERC20Token.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC20Token/IERC20Token.sol";
-import "../../tokens/ERC721Token/IERC721Token.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC721Token/IERC721Token.sol";
 import "./libs/LibConstants.sol";
 import "./mixins/MAssets.sol";
 

contracts/extensions/contracts/Forwarder/MixinExchangeWrapper.sol

@@ -16,15 +16,15 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
 import "./libs/LibConstants.sol";
 import "./mixins/MExchangeWrapper.sol";
-import "../../protocol/Exchange/libs/LibAbiEncoder.sol";
+import "@0x/contracts-libs/contracts/libs/LibAbiEncoder.sol";
-import "../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../../protocol/Exchange/libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
-import "../../protocol/Exchange/libs/LibMath.sol";
+import "@0x/contracts-libs/contracts/libs/LibMath.sol";
 
 
 contract MixinExchangeWrapper is

contracts/extensions/contracts/Forwarder/MixinForwarderCore.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
 import "./libs/LibConstants.sol";
@@ -24,10 +24,10 @@ import "./mixins/MWeth.sol";
 import "./mixins/MAssets.sol";
 import "./mixins/MExchangeWrapper.sol";
 import "./interfaces/IForwarderCore.sol";
-import "../../utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
-import "../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../../protocol/Exchange/libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
-import "../../protocol/Exchange/libs/LibMath.sol";
+import "@0x/contracts-libs/contracts/libs/LibMath.sol";
 
 
 contract MixinForwarderCore is

contracts/extensions/contracts/Forwarder/MixinWeth.sol

@@ -16,9 +16,9 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
-import "../../protocol/Exchange/libs/LibMath.sol";
+import "@0x/contracts-libs/contracts/libs/LibMath.sol";
 import "./libs/LibConstants.sol";
 import "./mixins/MWeth.sol";
 

contracts/extensions/contracts/Forwarder/interfaces/IAssets.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract IAssets {

contracts/extensions/contracts/Forwarder/interfaces/IForwarder.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
 import "./IForwarderCore.sol";

contracts/extensions/contracts/Forwarder/interfaces/IForwarderCore.sol

@@ -16,11 +16,11 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../../../protocol/Exchange/libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
 
 
 contract IForwarderCore {

contracts/extensions/contracts/Forwarder/libs/LibConstants.sol

@@ -16,12 +16,12 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
-import "../../../utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
-import "../../../protocol/Exchange/interfaces/IExchange.sol";
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
-import "../../../tokens/EtherToken/IEtherToken.sol";
+import "@0x/contracts-tokens/contracts/tokens/EtherToken/IEtherToken.sol";
-import "../../../tokens/ERC20Token/IERC20Token.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC20Token/IERC20Token.sol";
 
 
 contract LibConstants {

contracts/extensions/contracts/Forwarder/libs/LibForwarderErrors.sol

@@ -17,7 +17,7 @@
 */
 
 // solhint-disable
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 /// This contract is intended to serve as a reference, but is not actually used for efficiency reasons.

contracts/extensions/contracts/Forwarder/mixins/MAssets.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 import "../interfaces/IAssets.sol";
 

contracts/extensions/contracts/Forwarder/mixins/MExchangeWrapper.sol

@@ -16,11 +16,11 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../../../protocol/Exchange/libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
 
 
 contract MExchangeWrapper {

contracts/extensions/contracts/Forwarder/mixins/MWeth.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract MWeth {

contracts/extensions/contracts/OrderMatcher/MixinAssets.sol

@@ -0,0 +1,195 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/Ownable/Ownable.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC20Token/IERC20Token.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC721Token/IERC721Token.sol";
+import "./mixins/MAssets.sol";
+import "./libs/LibConstants.sol";
+
+
+contract MixinAssets is
+    MAssets,
+    Ownable,
+    LibConstants
+{
+    using LibBytes for bytes;
+
+    /// @dev Withdraws assets from this contract. The contract requires a ZRX balance in order to 
+    ///      function optimally, and this function allows the ZRX to be withdrawn by owner. It may also be
+    ///      used to withdraw assets that were accidentally sent to this contract.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to withdraw.
+    function withdrawAsset(
+        bytes assetData,
+        uint256 amount
+    )
+        external
+        onlyOwner
+    {
+        transferAssetToSender(assetData, amount);
+    }
+
+    /// @dev Approves or disapproves an AssetProxy to spend asset.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to approve for respective proxy.
+    function approveAssetProxy(
+        bytes assetData,
+        uint256 amount
+    )
+        external
+        onlyOwner
+    {
+        bytes4 proxyId = assetData.readBytes4(0);
+
+        if (proxyId == ERC20_DATA_ID) {
+            approveERC20Token(assetData, amount);
+        } else if (proxyId == ERC721_DATA_ID) {
+            approveERC721Token(assetData, amount);
+        } else {
+            revert("UNSUPPORTED_ASSET_PROXY");
+        }
+    }
+
+    /// @dev Transfers given amount of asset to sender.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to transfer to sender.
+    function transferAssetToSender(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal
+    {
+        bytes4 proxyId = assetData.readBytes4(0);
+
+        if (proxyId == ERC20_DATA_ID) {
+            transferERC20Token(assetData, amount);
+        } else if (proxyId == ERC721_DATA_ID) {
+            transferERC721Token(assetData, amount);
+        } else {
+            revert("UNSUPPORTED_ASSET_PROXY");
+        }
+    }
+
+    /// @dev Decodes ERC20 assetData and transfers given amount to sender.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to transfer to sender.
+    function transferERC20Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal
+    {
+        // 4 byte id + 12 0 bytes before ABI encoded token address.
+        address token = assetData.readAddress(16);
+
+        // Transfer tokens.
+        // We do a raw call so we can check the success separate
+        // from the return data.
+        bool success = token.call(abi.encodeWithSelector(
+            ERC20_TRANSFER_SELECTOR,
+            msg.sender,
+            amount
+        ));
+        require(
+            success,
+            "TRANSFER_FAILED"
+        );
+        
+        // Check return data.
+        // If there is no return data, we assume the token incorrectly
+        // does not return a bool. In this case we expect it to revert
+        // on failure, which was handled above.
+        // If the token does return data, we require that it is a single
+        // value that evaluates to true.
+        assembly {
+            if returndatasize {
+                success := 0
+                if eq(returndatasize, 32) {
+                    // First 64 bytes of memory are reserved scratch space
+                    returndatacopy(0, 0, 32)
+                    success := mload(0)
+                }
+            }
+        }
+        require(
+            success,
+            "TRANSFER_FAILED"
+        );
+    }
+
+    /// @dev Decodes ERC721 assetData and transfers given amount to sender.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to transfer to sender.
+    function transferERC721Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal
+    {
+        require(
+            amount == 1,
+            "INVALID_AMOUNT"
+        );
+        // Decode asset data.
+        // 4 byte id + 12 0 bytes before ABI encoded token address.
+        address token = assetData.readAddress(16);
+        // 4 byte id + 32 byte ABI encoded token address before token id.
+        uint256 tokenId = assetData.readUint256(36);
+
+        // Perform transfer.
+        IERC721Token(token).transferFrom(
+            address(this),
+            msg.sender,
+            tokenId
+        );
+    }
+
+    /// @dev Sets approval for ERC20 AssetProxy.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to approve for respective proxy.
+    function approveERC20Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal
+    {
+        address token = assetData.readAddress(16);
+        require(
+            IERC20Token(token).approve(ERC20_PROXY_ADDRESS, amount),
+            "APPROVAL_FAILED"
+        );
+    }
+
+    /// @dev Sets approval for ERC721 AssetProxy.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to approve for respective proxy.
+    function approveERC721Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal
+    {
+        address token = assetData.readAddress(16);
+        bool approval = amount >= 1;
+        IERC721Token(token).setApprovalForAll(ERC721_PROXY_ADDRESS, approval);
+    }
+}

contracts/extensions/contracts/OrderMatcher/MixinMatchOrders.sol

@@ -0,0 +1,86 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+pragma experimental ABIEncoderV2;
+
+import "./libs/LibConstants.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
+import "@0x/contracts-utils/contracts/utils/Ownable/Ownable.sol";
+
+
+contract MixinMatchOrders is
+    Ownable,
+    LibConstants
+{
+    /// @dev Match two complementary orders that have a profitable spread.
+    ///      Each order is filled at their respective price point. However, the calculations are
+    ///      carried out as though the orders are both being filled at the right order's price point.
+    ///      The profit made by the left order is then used to fill the right order as much as possible.
+    ///      This results in a spread being taken in terms of both assets. The spread is held within this contract.
+    /// @param leftOrder First order to match.
+    /// @param rightOrder Second order to match.
+    /// @param leftSignature Proof that order was created by the left maker.
+    /// @param rightSignature Proof that order was created by the right maker.
+    function matchOrders(
+        LibOrder.Order memory leftOrder,
+        LibOrder.Order memory rightOrder,
+        bytes memory leftSignature,
+        bytes memory rightSignature
+    )
+        public
+        onlyOwner
+    {
+        // Match orders, maximally filling `leftOrder`
+        LibFillResults.MatchedFillResults memory matchedFillResults = EXCHANGE.matchOrders(
+            leftOrder,
+            rightOrder,
+            leftSignature,
+            rightSignature
+        );
+
+        uint256 leftMakerAssetSpreadAmount = matchedFillResults.leftMakerAssetSpreadAmount;
+        uint256 rightOrderTakerAssetAmount = rightOrder.takerAssetAmount;
+
+        // Do not attempt to call `fillOrder` if no spread was taken or `rightOrder` has been completely filled
+        if (leftMakerAssetSpreadAmount == 0 || matchedFillResults.right.takerAssetFilledAmount == rightOrderTakerAssetAmount) {
+            return;
+        }
+
+        // The `assetData` fields of the `rightOrder` could have been null for the `matchOrders` call. We reassign them before calling `fillOrder`.
+        rightOrder.makerAssetData = leftOrder.takerAssetData;
+        rightOrder.takerAssetData = leftOrder.makerAssetData;
+
+        // Query `rightOrder` info to check if it has been completely filled
+        // We need to make this check in case the `rightOrder` was partially filled before the `matchOrders` call
+        LibOrder.OrderInfo memory orderInfo = EXCHANGE.getOrderInfo(rightOrder);
+
+        // Do not attempt to call `fillOrder` if order has been completely filled
+        if (orderInfo.orderTakerAssetFilledAmount == rightOrderTakerAssetAmount) {
+            return;
+        }
+
+        // We do not need to pass in a signature since it was already validated in the `matchOrders` call
+        EXCHANGE.fillOrder(
+            rightOrder,
+            leftMakerAssetSpreadAmount,
+            ""
+        );
+    }
+}

contracts/extensions/contracts/OrderMatcher/OrderMatcher.sol

@@ -0,0 +1,38 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity 0.4.24;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-utils/contracts/utils/Ownable/Ownable.sol";
+import "./libs/LibConstants.sol";
+import "./MixinMatchOrders.sol";
+import "./MixinAssets.sol";
+
+
+// solhint-disable no-empty-blocks
+contract OrderMatcher is
+    MixinMatchOrders,
+    MixinAssets
+{
+    constructor (address _exchange)
+        public
+        LibConstants(_exchange)
+        Ownable()
+    {}
+}

contracts/extensions/contracts/OrderMatcher/interfaces/IAssets.sol

@@ -0,0 +1,43 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+
+contract IAssets {
+
+    /// @dev Withdraws assets from this contract. The contract requires a ZRX balance in order to 
+    ///      function optimally, and this function allows the ZRX to be withdrawn by owner. It may also be
+    ///      used to withdraw assets that were accidentally sent to this contract.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to withdraw.
+    function withdrawAsset(
+        bytes assetData,
+        uint256 amount
+    )
+        external;
+
+    /// @dev Approves or disapproves an AssetProxy to spend asset.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to approve for respective proxy.
+    function approveAssetProxy(
+        bytes assetData,
+        uint256 amount
+    )
+        external;
+}

contracts/extensions/contracts/OrderMatcher/interfaces/IMatchOrders.sol

@@ -0,0 +1,43 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
+
+
+contract IMatchOrders {
+
+    /// @dev Match two complementary orders that have a profitable spread.
+    ///      Each order is filled at their respective price point. However, the calculations are
+    ///      carried out as though the orders are both being filled at the right order's price point.
+    ///      The profit made by the left order is then used to fill the right order as much as possible.
+    ///      This results in a spread being taken in terms of both assets. The spread is held within this contract.
+    /// @param leftOrder First order to match.
+    /// @param rightOrder Second order to match.
+    /// @param leftSignature Proof that order was created by the left maker.
+    /// @param rightSignature Proof that order was created by the right maker.
+    function matchOrders(
+        LibOrder.Order memory leftOrder,
+        LibOrder.Order memory rightOrder,
+        bytes memory leftSignature,
+        bytes memory rightSignature
+    )
+        public;
+}

contracts/extensions/contracts/OrderMatcher/interfaces/IOrderMatcher.sol

@@ -0,0 +1,31 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "@0x/contract-utils/contracts/utils/Ownable/IOwnable.sol";
+import "./IMatchOrders.sol";
+import "./IAssets.sol";
+
+
+// solhint-disable no-empty-blocks
+contract IOrderMatcher is
+    IOwnable,
+    IMatchOrders,
+    IAssets
+{}

contracts/extensions/contracts/OrderMatcher/libs/LibConstants.sol

@@ -0,0 +1,56 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
+
+
+contract LibConstants {
+
+    // bytes4(keccak256("transfer(address,uint256)"))
+    bytes4 constant internal ERC20_TRANSFER_SELECTOR = 0xa9059cbb;
+    // bytes4(keccak256("ERC20Token(address)"))
+    bytes4 constant internal ERC20_DATA_ID = 0xf47261b0;
+    // bytes4(keccak256("ERC721Token(address,uint256)"))
+    bytes4 constant internal ERC721_DATA_ID = 0x02571792;
+ 
+     // solhint-disable var-name-mixedcase
+    IExchange internal EXCHANGE;
+    address internal ERC20_PROXY_ADDRESS;
+    address internal ERC721_PROXY_ADDRESS;
+    // solhint-enable var-name-mixedcase
+
+    constructor (address _exchange)
+        public
+    {
+        EXCHANGE = IExchange(_exchange);
+
+        ERC20_PROXY_ADDRESS = EXCHANGE.getAssetProxy(ERC20_DATA_ID);
+        require(
+            ERC20_PROXY_ADDRESS != address(0),
+            "UNREGISTERED_ASSET_PROXY"
+        );
+
+        ERC721_PROXY_ADDRESS = EXCHANGE.getAssetProxy(ERC721_DATA_ID);
+        require(
+            ERC721_PROXY_ADDRESS != address(0),
+            "UNREGISTERED_ASSET_PROXY"
+        );
+    }
+}

contracts/extensions/contracts/OrderMatcher/mixins/MAssets.sol

@@ -0,0 +1,71 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "../interfaces/IAssets.sol";
+
+
+contract MAssets is
+    IAssets
+{
+    /// @dev Transfers given amount of asset to sender.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to transfer to sender.
+    function transferAssetToSender(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal;
+
+    /// @dev Decodes ERC20 assetData and transfers given amount to sender.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to transfer to sender.
+    function transferERC20Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal;
+
+    /// @dev Decodes ERC721 assetData and transfers given amount to sender.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to transfer to sender.
+    function transferERC721Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal;
+
+    /// @dev Sets approval for ERC20 AssetProxy.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to approve for respective proxy.
+    function approveERC20Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal;
+
+    /// @dev Sets approval for ERC721 AssetProxy.
+    /// @param assetData Byte array encoded for the respective asset proxy.
+    /// @param amount Amount of asset to approve for respective proxy.
+    function approveERC721Token(
+        bytes memory assetData,
+        uint256 amount
+    )
+        internal;
+}

contracts/extensions/contracts/OrderValidator/OrderValidator.sol

@@ -19,11 +19,11 @@
 pragma solidity 0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../../protocol/Exchange/interfaces/IExchange.sol";
+import "@0x/contracts-interfaces/contracts/protocol/Exchange/IExchange.sol";
-import "../../protocol/Exchange/libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../../tokens/ERC20Token/IERC20Token.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC20Token/IERC20Token.sol";
-import "../../tokens/ERC721Token/IERC721Token.sol";
+import "@0x/contracts-tokens/contracts/tokens/ERC721Token/IERC721Token.sol";
-import "../../utils/LibBytes/LibBytes.sol";
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
 
 
 contract OrderValidator {

contracts/extensions/package.json

@@ -0,0 +1,94 @@
+{
+    "name": "@0x/contracts-extensions",
+    "version": "1.0.2",
+    "engines": {
+        "node": ">=6.12"
+    },
+    "description": "Smart contract extensions of 0x protocol",
+    "main": "lib/src/index.js",
+    "directories": {
+        "test": "test"
+    },
+    "scripts": {
+        "build": "yarn pre_build && tsc -b",
+        "build:ci": "yarn build",
+        "pre_build": "run-s compile generate_contract_wrappers",
+        "test": "yarn run_mocha",
+        "rebuild_and_test": "run-s build test",
+        "test:coverage": "SOLIDITY_COVERAGE=true run-s build run_mocha coverage:report:text coverage:report:lcov",
+        "test:profiler": "SOLIDITY_PROFILER=true run-s build run_mocha profiler:report:html",
+        "test:trace": "SOLIDITY_REVERT_TRACE=true run-s build run_mocha",
+        "run_mocha": "mocha --require source-map-support/register --require make-promises-safe 'lib/test/**/*.js' --timeout 100000 --bail --exit",
+        "compile": "sol-compiler",
+        "watch": "sol-compiler -w",
+        "clean": "shx rm -rf lib generated-artifacts generated-wrappers",
+        "generate_contract_wrappers": "abi-gen --abis  ${npm_package_config_abis} --template ../../node_modules/@0x/abi-gen-templates/contract.handlebars --partials '../../node_modules/@0x/abi-gen-templates/partials/**/*.handlebars' --output generated-wrappers --backend ethers",
+        "lint": "tslint --format stylish --project . --exclude ./generated-wrappers/**/* --exclude ./generated-artifacts/**/* --exclude **/lib/**/* && yarn lint-contracts",
+        "coverage:report:text": "istanbul report text",
+        "coverage:report:html": "istanbul report html && open coverage/index.html",
+        "profiler:report:html": "istanbul report html && open coverage/index.html",
+        "coverage:report:lcov": "istanbul report lcov",
+        "test:circleci": "yarn test",
+        "lint-contracts": "solhint -c ../.solhint.json contracts/**/**/**/**/*.sol"
+    },
+    "config": {
+        "abis": "generated-artifacts/@(BalanceThresholdFilter|DutchAuction|Forwarder|OrderMatcher|OrderValidator).json"
+    },
+    "repository": {
+        "type": "git",
+        "url": "https://github.com/0xProject/0x-monorepo.git"
+    },
+    "license": "Apache-2.0",
+    "bugs": {
+        "url": "https://github.com/0xProject/0x-monorepo/issues"
+    },
+    "homepage": "https://github.com/0xProject/0x-monorepo/contracts/extensions/README.md",
+    "devDependencies": {
+        "@0x/abi-gen": "^1.0.19",
+        "@0x/contracts-test-utils": "^1.0.2",
+        "@0x/dev-utils": "^1.0.21",
+        "@0x/sol-compiler": "^1.1.16",
+        "@0x/sol-cov": "^2.1.16",
+        "@0x/subproviders": "^2.1.8",
+        "@0x/tslint-config": "^2.0.0",
+        "@types/bn.js": "^4.11.0",
+        "@types/lodash": "4.14.104",
+        "@types/node": "*",
+        "@types/yargs": "^10.0.0",
+        "chai": "^4.0.1",
+        "chai-as-promised": "^7.1.0",
+        "chai-bignumber": "^2.0.1",
+        "dirty-chai": "^2.0.1",
+        "ethereumjs-abi": "0.6.5",
+        "make-promises-safe": "^1.1.0",
+        "mocha": "^4.1.0",
+        "npm-run-all": "^4.1.2",
+        "shx": "^0.2.2",
+        "solc": "^0.4.24",
+        "solhint": "^1.4.1",
+        "tslint": "5.11.0",
+        "typescript": "3.0.1",
+        "yargs": "^10.0.3"
+    },
+    "dependencies": {
+        "@0x/base-contract": "^3.0.10",
+        "@0x/contracts-interfaces": "^1.0.2",
+        "@0x/contracts-libs": "^1.0.2",
+        "@0x/contracts-protocol": "^2.1.59",
+        "@0x/contracts-tokens": "^1.0.2",
+        "@0x/contracts-utils": "^1.0.2",
+        "@0x/order-utils": "^3.0.7",
+        "@0x/types": "^1.4.1",
+        "@0x/typescript-typings": "^3.0.6",
+        "@0x/utils": "^2.0.8",
+        "@0x/web3-wrapper": "^3.2.1",
+        "@types/js-combinatorics": "^0.5.29",
+        "bn.js": "^4.11.8",
+        "ethereum-types": "^1.1.4",
+        "ethereumjs-util": "^5.1.1",
+        "lodash": "^4.17.5"
+    },
+    "publishConfig": {
+        "access": "public"
+    }
+}

contracts/extensions/src/artifacts/index.ts

@@ -0,0 +1,15 @@
+import { ContractArtifact } from 'ethereum-types';
+
+import * as BalanceThresholdFilter from '../../generated-artifacts/BalanceThresholdFilter.json';
+import * as DutchAuction from '../../generated-artifacts/DutchAuction.json';
+import * as Forwarder from '../../generated-artifacts/Forwarder.json';
+import * as OrderMatcher from '../../generated-artifacts/OrderMatcher.json';
+import * as OrderValidator from '../../generated-artifacts/OrderValidator.json';
+
+export const artifacts = {
+    BalanceThresholdFilter: BalanceThresholdFilter as ContractArtifact,
+    DutchAuction: DutchAuction as ContractArtifact,
+    Forwarder: Forwarder as ContractArtifact,
+    OrderMatcher: OrderMatcher as ContractArtifact,
+    OrderValidator: OrderValidator as ContractArtifact,
+};

contracts/extensions/src/index.ts

@@ -0,0 +1,2 @@
+export * from './artifacts';
+export * from './wrappers';

contracts/extensions/src/wrappers/index.ts

@@ -0,0 +1,5 @@
+export * from '../../generated-wrappers/balance_threshold_filter';
+export * from '../../generated-wrappers/dutch_auction';
+export * from '../../generated-wrappers/forwarder';
+export * from '../../generated-wrappers/order_matcher';
+export * from '../../generated-wrappers/order_validator';

contracts/extensions/test/extensions/dutch_auction.ts

@@ -0,0 +1,458 @@
+import {
+    artifacts as protocolArtifacts,
+    ERC20Wrapper,
+    ERC721Wrapper,
+    ExchangeContract,
+    ExchangeWrapper,
+} from '@0x/contracts-protocol';
+import {
+    chaiSetup,
+    constants,
+    ContractName,
+    ERC20BalancesByOwner,
+    expectTransactionFailedAsync,
+    getLatestBlockTimestampAsync,
+    OrderFactory,
+    provider,
+    txDefaults,
+    web3Wrapper,
+} from '@0x/contracts-test-utils';
+import {
+    artifacts as tokensArtifacts,
+    DummyERC20TokenContract,
+    DummyERC721TokenContract,
+    WETH9Contract,
+} from '@0x/contracts-tokens';
+import { BlockchainLifecycle } from '@0x/dev-utils';
+import { assetDataUtils, generatePseudoRandomSalt } from '@0x/order-utils';
+import { RevertReason, SignedOrder } from '@0x/types';
+import { BigNumber } from '@0x/utils';
+import { Web3Wrapper } from '@0x/web3-wrapper';
+import * as chai from 'chai';
+import ethAbi = require('ethereumjs-abi');
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { DutchAuctionContract } from '../../generated-wrappers/dutch_auction';
+import { artifacts } from '../../src/artifacts';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+const DECIMALS_DEFAULT = 18;
+
+describe(ContractName.DutchAuction, () => {
+    let makerAddress: string;
+    let owner: string;
+    let takerAddress: string;
+    let feeRecipientAddress: string;
+    let defaultMakerAssetAddress: string;
+
+    let zrxToken: DummyERC20TokenContract;
+    let erc20TokenA: DummyERC20TokenContract;
+    let erc721Token: DummyERC721TokenContract;
+    let dutchAuctionContract: DutchAuctionContract;
+    let wethContract: WETH9Contract;
+
+    let sellerOrderFactory: OrderFactory;
+    let buyerOrderFactory: OrderFactory;
+    let erc20Wrapper: ERC20Wrapper;
+    let erc20Balances: ERC20BalancesByOwner;
+    let currentBlockTimestamp: number;
+    let auctionBeginTimeSeconds: BigNumber;
+    let auctionEndTimeSeconds: BigNumber;
+    let auctionBeginAmount: BigNumber;
+    let auctionEndAmount: BigNumber;
+    let sellOrder: SignedOrder;
+    let buyOrder: SignedOrder;
+    let erc721MakerAssetIds: BigNumber[];
+    const tenMinutesInSeconds = 10 * 60;
+
+    function extendMakerAssetData(makerAssetData: string, beginTimeSeconds: BigNumber, beginAmount: BigNumber): string {
+        return ethUtil.bufferToHex(
+            Buffer.concat([
+                ethUtil.toBuffer(makerAssetData),
+                ethUtil.toBuffer(
+                    (ethAbi as any).rawEncode(
+                        ['uint256', 'uint256'],
+                        [beginTimeSeconds.toString(), beginAmount.toString()],
+                    ),
+                ),
+            ]),
+        );
+    }
+
+    before(async () => {
+        await blockchainLifecycle.startAsync();
+        const accounts = await web3Wrapper.getAvailableAddressesAsync();
+        const usedAddresses = ([owner, makerAddress, takerAddress, feeRecipientAddress] = accounts);
+
+        erc20Wrapper = new ERC20Wrapper(provider, usedAddresses, owner);
+
+        const numDummyErc20ToDeploy = 2;
+        [erc20TokenA, zrxToken] = await erc20Wrapper.deployDummyTokensAsync(
+            numDummyErc20ToDeploy,
+            constants.DUMMY_TOKEN_DECIMALS,
+        );
+        const erc20Proxy = await erc20Wrapper.deployProxyAsync();
+        await erc20Wrapper.setBalancesAndAllowancesAsync();
+
+        const erc721Wrapper = new ERC721Wrapper(provider, usedAddresses, owner);
+        [erc721Token] = await erc721Wrapper.deployDummyTokensAsync();
+        const erc721Proxy = await erc721Wrapper.deployProxyAsync();
+        await erc721Wrapper.setBalancesAndAllowancesAsync();
+        const erc721Balances = await erc721Wrapper.getBalancesAsync();
+        erc721MakerAssetIds = erc721Balances[makerAddress][erc721Token.address];
+
+        wethContract = await WETH9Contract.deployFrom0xArtifactAsync(tokensArtifacts.WETH9, provider, txDefaults);
+        erc20Wrapper.addDummyTokenContract(wethContract as any);
+
+        const zrxAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
+        const exchangeInstance = await ExchangeContract.deployFrom0xArtifactAsync(
+            protocolArtifacts.Exchange,
+            provider,
+            txDefaults,
+            zrxAssetData,
+        );
+        const exchangeWrapper = new ExchangeWrapper(exchangeInstance, provider);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
+
+        await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeInstance.address, {
+            from: owner,
+        });
+        await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeInstance.address, {
+            from: owner,
+        });
+
+        const dutchAuctionInstance = await DutchAuctionContract.deployFrom0xArtifactAsync(
+            artifacts.DutchAuction,
+            provider,
+            txDefaults,
+            exchangeInstance.address,
+        );
+        dutchAuctionContract = new DutchAuctionContract(
+            dutchAuctionInstance.abi,
+            dutchAuctionInstance.address,
+            provider,
+        );
+
+        defaultMakerAssetAddress = erc20TokenA.address;
+        const defaultTakerAssetAddress = wethContract.address;
+
+        // Set up taker WETH balance and allowance
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await wethContract.deposit.sendTransactionAsync({
+                from: takerAddress,
+                value: Web3Wrapper.toBaseUnitAmount(new BigNumber(50), DECIMALS_DEFAULT),
+            }),
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await wethContract.approve.sendTransactionAsync(
+                erc20Proxy.address,
+                constants.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
+                { from: takerAddress },
+            ),
+        );
+        web3Wrapper.abiDecoder.addABI(exchangeInstance.abi);
+        web3Wrapper.abiDecoder.addABI(zrxToken.abi);
+        erc20Wrapper.addTokenOwnerAddress(dutchAuctionContract.address);
+
+        currentBlockTimestamp = await getLatestBlockTimestampAsync();
+        // Default auction begins 10 minutes ago
+        auctionBeginTimeSeconds = new BigNumber(currentBlockTimestamp).minus(tenMinutesInSeconds);
+        // Default auction ends 10 from now
+        auctionEndTimeSeconds = new BigNumber(currentBlockTimestamp).plus(tenMinutesInSeconds);
+        auctionBeginAmount = Web3Wrapper.toBaseUnitAmount(new BigNumber(10), DECIMALS_DEFAULT);
+        auctionEndAmount = Web3Wrapper.toBaseUnitAmount(new BigNumber(1), DECIMALS_DEFAULT);
+
+        // Default sell order and buy order are exact mirrors
+        const sellerDefaultOrderParams = {
+            salt: generatePseudoRandomSalt(),
+            exchangeAddress: exchangeInstance.address,
+            makerAddress,
+            feeRecipientAddress,
+            // taker address or sender address should be set to the ducth auction contract
+            takerAddress: dutchAuctionContract.address,
+            makerAssetData: extendMakerAssetData(
+                assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
+                auctionBeginTimeSeconds,
+                auctionBeginAmount,
+            ),
+            takerAssetData: assetDataUtils.encodeERC20AssetData(defaultTakerAssetAddress),
+            makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(200), DECIMALS_DEFAULT),
+            takerAssetAmount: auctionEndAmount,
+            expirationTimeSeconds: auctionEndTimeSeconds,
+            makerFee: constants.ZERO_AMOUNT,
+            takerFee: constants.ZERO_AMOUNT,
+        };
+        // Default buy order is for the auction begin price
+        const buyerDefaultOrderParams = {
+            ...sellerDefaultOrderParams,
+            makerAddress: takerAddress,
+            makerAssetData: sellerDefaultOrderParams.takerAssetData,
+            takerAssetData: sellerDefaultOrderParams.makerAssetData,
+            makerAssetAmount: auctionBeginAmount,
+            takerAssetAmount: sellerDefaultOrderParams.makerAssetAmount,
+        };
+        const makerPrivateKey = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddress)];
+        const takerPrivateKey = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(takerAddress)];
+        sellerOrderFactory = new OrderFactory(makerPrivateKey, sellerDefaultOrderParams);
+        buyerOrderFactory = new OrderFactory(takerPrivateKey, buyerDefaultOrderParams);
+    });
+    after(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+        erc20Balances = await erc20Wrapper.getBalancesAsync();
+        sellOrder = await sellerOrderFactory.newSignedOrderAsync();
+        buyOrder = await buyerOrderFactory.newSignedOrderAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('matchOrders', () => {
+        it('should be worth the begin price at the begining of the auction', async () => {
+            auctionBeginTimeSeconds = new BigNumber(currentBlockTimestamp + 2);
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                makerAssetData: extendMakerAssetData(
+                    assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
+                    auctionBeginTimeSeconds,
+                    auctionBeginAmount,
+                ),
+            });
+            const auctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+            expect(auctionDetails.currentAmount).to.be.bignumber.equal(auctionBeginAmount);
+            expect(auctionDetails.beginAmount).to.be.bignumber.equal(auctionBeginAmount);
+        });
+        it('should be be worth the end price at the end of the auction', async () => {
+            auctionBeginTimeSeconds = new BigNumber(currentBlockTimestamp - tenMinutesInSeconds * 2);
+            auctionEndTimeSeconds = new BigNumber(currentBlockTimestamp - tenMinutesInSeconds);
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                makerAssetData: extendMakerAssetData(
+                    assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
+                    auctionBeginTimeSeconds,
+                    auctionBeginAmount,
+                ),
+                expirationTimeSeconds: auctionEndTimeSeconds,
+            });
+            const auctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+            expect(auctionDetails.currentAmount).to.be.bignumber.equal(auctionEndAmount);
+            expect(auctionDetails.beginAmount).to.be.bignumber.equal(auctionBeginAmount);
+        });
+        it('should match orders at current amount and send excess to buyer', async () => {
+            const beforeAuctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+            buyOrder = await buyerOrderFactory.newSignedOrderAsync({
+                makerAssetAmount: beforeAuctionDetails.currentAmount.times(2),
+            });
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await dutchAuctionContract.matchOrders.sendTransactionAsync(
+                    buyOrder,
+                    sellOrder,
+                    buyOrder.signature,
+                    sellOrder.signature,
+                    {
+                        from: takerAddress,
+                    },
+                ),
+            );
+            const afterAuctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+            const newBalances = await erc20Wrapper.getBalancesAsync();
+            expect(newBalances[dutchAuctionContract.address][wethContract.address]).to.be.bignumber.equal(
+                constants.ZERO_AMOUNT,
+            );
+            // HACK gte used here due to a bug in ganache where the timestamp can change
+            // between multiple calls to the same block. Which can move the amount in our case
+            // ref: https://github.com/trufflesuite/ganache-core/issues/111
+            expect(newBalances[makerAddress][wethContract.address]).to.be.bignumber.gte(
+                erc20Balances[makerAddress][wethContract.address].plus(afterAuctionDetails.currentAmount),
+            );
+            expect(newBalances[takerAddress][wethContract.address]).to.be.bignumber.gte(
+                erc20Balances[takerAddress][wethContract.address].minus(beforeAuctionDetails.currentAmount),
+            );
+        });
+        it('maker fees on sellOrder are paid to the fee receipient', async () => {
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                makerFee: new BigNumber(1),
+            });
+            const txHash = await dutchAuctionContract.matchOrders.sendTransactionAsync(
+                buyOrder,
+                sellOrder,
+                buyOrder.signature,
+                sellOrder.signature,
+                {
+                    from: takerAddress,
+                },
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(txHash);
+            const afterAuctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+            const newBalances = await erc20Wrapper.getBalancesAsync();
+            expect(newBalances[makerAddress][wethContract.address]).to.be.bignumber.gte(
+                erc20Balances[makerAddress][wethContract.address].plus(afterAuctionDetails.currentAmount),
+            );
+            expect(newBalances[feeRecipientAddress][zrxToken.address]).to.be.bignumber.equal(
+                erc20Balances[feeRecipientAddress][zrxToken.address].plus(sellOrder.makerFee),
+            );
+        });
+        it('maker fees on buyOrder are paid to the fee receipient', async () => {
+            buyOrder = await buyerOrderFactory.newSignedOrderAsync({
+                makerFee: new BigNumber(1),
+            });
+            const txHash = await dutchAuctionContract.matchOrders.sendTransactionAsync(
+                buyOrder,
+                sellOrder,
+                buyOrder.signature,
+                sellOrder.signature,
+                {
+                    from: takerAddress,
+                },
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(txHash);
+            const newBalances = await erc20Wrapper.getBalancesAsync();
+            const afterAuctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+            expect(newBalances[makerAddress][wethContract.address]).to.be.bignumber.gte(
+                erc20Balances[makerAddress][wethContract.address].plus(afterAuctionDetails.currentAmount),
+            );
+            expect(newBalances[feeRecipientAddress][zrxToken.address]).to.be.bignumber.equal(
+                erc20Balances[feeRecipientAddress][zrxToken.address].plus(buyOrder.makerFee),
+            );
+        });
+        it('should revert when auction expires', async () => {
+            auctionBeginTimeSeconds = new BigNumber(currentBlockTimestamp - tenMinutesInSeconds * 2);
+            auctionEndTimeSeconds = new BigNumber(currentBlockTimestamp - tenMinutesInSeconds);
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                expirationTimeSeconds: auctionEndTimeSeconds,
+                makerAssetData: extendMakerAssetData(
+                    assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
+                    auctionBeginTimeSeconds,
+                    auctionBeginAmount,
+                ),
+            });
+            return expectTransactionFailedAsync(
+                dutchAuctionContract.matchOrders.sendTransactionAsync(
+                    buyOrder,
+                    sellOrder,
+                    buyOrder.signature,
+                    sellOrder.signature,
+                    {
+                        from: takerAddress,
+                    },
+                ),
+                RevertReason.AuctionExpired,
+            );
+        });
+        it('cannot be filled for less than the current price', async () => {
+            buyOrder = await buyerOrderFactory.newSignedOrderAsync({
+                makerAssetAmount: sellOrder.takerAssetAmount,
+            });
+            return expectTransactionFailedAsync(
+                dutchAuctionContract.matchOrders.sendTransactionAsync(
+                    buyOrder,
+                    sellOrder,
+                    buyOrder.signature,
+                    sellOrder.signature,
+                    {
+                        from: takerAddress,
+                    },
+                ),
+                RevertReason.AuctionInvalidAmount,
+            );
+        });
+        it('auction begin amount must be higher than final amount ', async () => {
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                takerAssetAmount: auctionBeginAmount.plus(1),
+            });
+            return expectTransactionFailedAsync(
+                dutchAuctionContract.matchOrders.sendTransactionAsync(
+                    buyOrder,
+                    sellOrder,
+                    buyOrder.signature,
+                    sellOrder.signature,
+                    {
+                        from: takerAddress,
+                    },
+                ),
+                RevertReason.AuctionInvalidAmount,
+            );
+        });
+        it('begin time is less than end time', async () => {
+            auctionBeginTimeSeconds = new BigNumber(auctionEndTimeSeconds).plus(tenMinutesInSeconds);
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                expirationTimeSeconds: auctionEndTimeSeconds,
+                makerAssetData: extendMakerAssetData(
+                    assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
+                    auctionBeginTimeSeconds,
+                    auctionBeginAmount,
+                ),
+            });
+            return expectTransactionFailedAsync(
+                dutchAuctionContract.matchOrders.sendTransactionAsync(
+                    buyOrder,
+                    sellOrder,
+                    buyOrder.signature,
+                    sellOrder.signature,
+                    {
+                        from: takerAddress,
+                    },
+                ),
+                RevertReason.AuctionInvalidBeginTime,
+            );
+        });
+        it('asset data contains auction parameters', async () => {
+            sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                makerAssetData: assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
+            });
+            return expectTransactionFailedAsync(
+                dutchAuctionContract.matchOrders.sendTransactionAsync(
+                    buyOrder,
+                    sellOrder,
+                    buyOrder.signature,
+                    sellOrder.signature,
+                    {
+                        from: takerAddress,
+                    },
+                ),
+                RevertReason.InvalidAssetData,
+            );
+        });
+        describe('ERC721', () => {
+            it('should match orders when ERC721', async () => {
+                const makerAssetId = erc721MakerAssetIds[0];
+                sellOrder = await sellerOrderFactory.newSignedOrderAsync({
+                    makerAssetAmount: new BigNumber(1),
+                    makerAssetData: extendMakerAssetData(
+                        assetDataUtils.encodeERC721AssetData(erc721Token.address, makerAssetId),
+                        auctionBeginTimeSeconds,
+                        auctionBeginAmount,
+                    ),
+                });
+                buyOrder = await buyerOrderFactory.newSignedOrderAsync({
+                    takerAssetAmount: new BigNumber(1),
+                    takerAssetData: sellOrder.makerAssetData,
+                });
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await dutchAuctionContract.matchOrders.sendTransactionAsync(
+                        buyOrder,
+                        sellOrder,
+                        buyOrder.signature,
+                        sellOrder.signature,
+                        {
+                            from: takerAddress,
+                        },
+                    ),
+                );
+                const afterAuctionDetails = await dutchAuctionContract.getAuctionDetails.callAsync(sellOrder);
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                // HACK gte used here due to a bug in ganache where the timestamp can change
+                // between multiple calls to the same block. Which can move the amount in our case
+                // ref: https://github.com/trufflesuite/ganache-core/issues/111
+                expect(newBalances[makerAddress][wethContract.address]).to.be.bignumber.gte(
+                    erc20Balances[makerAddress][wethContract.address].plus(afterAuctionDetails.currentAmount),
+                );
+                const newOwner = await erc721Token.ownerOf.callAsync(makerAssetId);
+                expect(newOwner).to.be.bignumber.equal(takerAddress);
+            });
+        });
+    });
+});

contracts/extensions/test/extensions/forwarder.ts

@@ -1,3 +1,29 @@
+import {
+    artifacts as protocolArtifacts,
+    ERC20Wrapper,
+    ERC721Wrapper,
+    ExchangeContract,
+    ExchangeWrapper,
+} from '@0x/contracts-protocol';
+import {
+    chaiSetup,
+    constants,
+    ContractName,
+    ERC20BalancesByOwner,
+    expectContractCreationFailedAsync,
+    expectTransactionFailedAsync,
+    OrderFactory,
+    provider,
+    sendTransactionResult,
+    txDefaults,
+    web3Wrapper,
+} from '@0x/contracts-test-utils';
+import {
+    artifacts as tokenArtifacts,
+    DummyERC20TokenContract,
+    DummyERC721TokenContract,
+    WETH9Contract,
+} from '@0x/contracts-tokens';
 import { BlockchainLifecycle } from '@0x/dev-utils';
 import { assetDataUtils } from '@0x/order-utils';
 import { RevertReason, SignedOrder } from '@0x/types';
@@ -6,26 +32,10 @@ import { Web3Wrapper } from '@0x/web3-wrapper';
 import * as chai from 'chai';
 import { TransactionReceiptWithDecodedLogs } from 'ethereum-types';
 
-import { DummyERC20TokenContract } from '../../generated-wrappers/dummy_erc20_token';
-import { DummyERC721TokenContract } from '../../generated-wrappers/dummy_erc721_token';
-import { ExchangeContract } from '../../generated-wrappers/exchange';
 import { ForwarderContract } from '../../generated-wrappers/forwarder';
-import { WETH9Contract } from '../../generated-wrappers/weth9';
 import { artifacts } from '../../src/artifacts';
-import {
+
-    expectContractCreationFailedAsync,
-    expectTransactionFailedAsync,
-    sendTransactionResult,
-} from '../utils/assertions';
-import { chaiSetup } from '../utils/chai_setup';
-import { constants } from '../utils/constants';
-import { ERC20Wrapper } from '../utils/erc20_wrapper';
-import { ERC721Wrapper } from '../utils/erc721_wrapper';
-import { ExchangeWrapper } from '../utils/exchange_wrapper';
 import { ForwarderWrapper } from '../utils/forwarder_wrapper';
-import { OrderFactory } from '../utils/order_factory';
-import { ContractName, ERC20BalancesByOwner } from '../utils/types';
-import { provider, txDefaults, web3Wrapper } from '../utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -38,7 +48,6 @@ describe(ContractName.Forwarder, () => {
     let owner: string;
     let takerAddress: string;
     let feeRecipientAddress: string;
-    let otherAddress: string;
     let defaultMakerAssetAddress: string;
     let zrxAssetData: string;
     let wethAssetData: string;
@@ -68,7 +77,7 @@ describe(ContractName.Forwarder, () => {
     before(async () => {
         await blockchainLifecycle.startAsync();
         const accounts = await web3Wrapper.getAvailableAddressesAsync();
-        const usedAddresses = ([owner, makerAddress, takerAddress, feeRecipientAddress, otherAddress] = accounts);
+        const usedAddresses = ([owner, makerAddress, takerAddress, feeRecipientAddress] = accounts);
 
         const txHash = await web3Wrapper.sendTransactionAsync({ from: accounts[0], to: accounts[0], value: 0 });
         const transaction = await web3Wrapper.getTransactionByHashAsync(txHash);
@@ -91,14 +100,14 @@ describe(ContractName.Forwarder, () => {
         const erc721Balances = await erc721Wrapper.getBalancesAsync();
         erc721MakerAssetIds = erc721Balances[makerAddress][erc721Token.address];
 
-        wethContract = await WETH9Contract.deployFrom0xArtifactAsync(artifacts.WETH9, provider, txDefaults);
+        wethContract = await WETH9Contract.deployFrom0xArtifactAsync(tokenArtifacts.WETH9, provider, txDefaults);
         weth = new DummyERC20TokenContract(wethContract.abi, wethContract.address, provider);
         erc20Wrapper.addDummyTokenContract(weth);
 
         wethAssetData = assetDataUtils.encodeERC20AssetData(wethContract.address);
         zrxAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
         const exchangeInstance = await ExchangeContract.deployFrom0xArtifactAsync(
-            artifacts.Exchange,
+            protocolArtifacts.Exchange,
             provider,
             txDefaults,
             zrxAssetData,
@@ -169,7 +178,7 @@ describe(ContractName.Forwarder, () => {
     describe('constructor', () => {
         it('should revert if assetProxy is unregistered', async () => {
             const exchangeInstance = await ExchangeContract.deployFrom0xArtifactAsync(
-                artifacts.Exchange,
+                protocolArtifacts.Exchange,
                 provider,
                 txDefaults,
                 zrxAssetData,

contracts/extensions/test/extensions/order_matcher.ts

@@ -0,0 +1,818 @@
+import {
+    artifacts as protocolArtifacts,
+    ERC20ProxyContract,
+    ERC20Wrapper,
+    ERC721ProxyContract,
+    ExchangeContract,
+    ExchangeFillEventArgs,
+    ExchangeWrapper,
+} from '@0x/contracts-protocol';
+import {
+    chaiSetup,
+    constants,
+    ERC20BalancesByOwner,
+    expectContractCreationFailedAsync,
+    expectTransactionFailedAsync,
+    LogDecoder,
+    OrderFactory,
+    provider,
+    sendTransactionResult,
+    txDefaults,
+    web3Wrapper,
+} from '@0x/contracts-test-utils';
+import { artifacts as tokenArtifacts, DummyERC20TokenContract, DummyERC721TokenContract } from '@0x/contracts-tokens';
+import { BlockchainLifecycle } from '@0x/dev-utils';
+import { assetDataUtils } from '@0x/order-utils';
+import { RevertReason } from '@0x/types';
+import { BigNumber } from '@0x/utils';
+import { Web3Wrapper } from '@0x/web3-wrapper';
+import * as chai from 'chai';
+import { LogWithDecodedArgs } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { OrderMatcherContract } from '../../generated-wrappers/order_matcher';
+import { artifacts } from '../../src/artifacts';
+
+const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+chaiSetup.configure();
+const expect = chai.expect;
+// tslint:disable:no-unnecessary-type-assertion
+describe('OrderMatcher', () => {
+    let makerAddressLeft: string;
+    let makerAddressRight: string;
+    let owner: string;
+    let takerAddress: string;
+    let feeRecipientAddressLeft: string;
+    let feeRecipientAddressRight: string;
+
+    let erc20TokenA: DummyERC20TokenContract;
+    let erc20TokenB: DummyERC20TokenContract;
+    let zrxToken: DummyERC20TokenContract;
+    let exchange: ExchangeContract;
+    let erc20Proxy: ERC20ProxyContract;
+    let erc721Proxy: ERC721ProxyContract;
+    let orderMatcher: OrderMatcherContract;
+
+    let erc20BalancesByOwner: ERC20BalancesByOwner;
+    let exchangeWrapper: ExchangeWrapper;
+    let erc20Wrapper: ERC20Wrapper;
+    let orderFactoryLeft: OrderFactory;
+    let orderFactoryRight: OrderFactory;
+
+    let leftMakerAssetData: string;
+    let leftTakerAssetData: string;
+    let defaultERC20MakerAssetAddress: string;
+    let defaultERC20TakerAssetAddress: string;
+
+    before(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    after(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    before(async () => {
+        // Create accounts
+        const accounts = await web3Wrapper.getAvailableAddressesAsync();
+        // Hack(albrow): Both Prettier and TSLint insert a trailing comma below
+        // but that is invalid syntax as of TypeScript version >= 2.8. We don't
+        // have the right fine-grained configuration options in TSLint,
+        // Prettier, or TypeScript, to reconcile this, so we will just have to
+        // wait for them to sort it out. We disable TSLint and Prettier for
+        // this part of the code for now. This occurs several times in this
+        // file. See https://github.com/prettier/prettier/issues/4624.
+        // prettier-ignore
+        const usedAddresses = ([
+            owner,
+            makerAddressLeft,
+            makerAddressRight,
+            takerAddress,
+            feeRecipientAddressLeft,
+            // tslint:disable-next-line:trailing-comma
+            feeRecipientAddressRight
+        ] = _.slice(accounts, 0, 6));
+        // Create wrappers
+        erc20Wrapper = new ERC20Wrapper(provider, usedAddresses, owner);
+        // Deploy ERC20 token & ERC20 proxy
+        const numDummyErc20ToDeploy = 3;
+        [erc20TokenA, erc20TokenB, zrxToken] = await erc20Wrapper.deployDummyTokensAsync(
+            numDummyErc20ToDeploy,
+            constants.DUMMY_TOKEN_DECIMALS,
+        );
+        erc20Proxy = await erc20Wrapper.deployProxyAsync();
+        await erc20Wrapper.setBalancesAndAllowancesAsync();
+        // Deploy ERC721 proxy
+        erc721Proxy = await ERC721ProxyContract.deployFrom0xArtifactAsync(
+            protocolArtifacts.ERC721Proxy,
+            provider,
+            txDefaults,
+        );
+        // Depoy exchange
+        exchange = await ExchangeContract.deployFrom0xArtifactAsync(
+            protocolArtifacts.Exchange,
+            provider,
+            txDefaults,
+            assetDataUtils.encodeERC20AssetData(zrxToken.address),
+        );
+        exchangeWrapper = new ExchangeWrapper(exchange, provider);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
+        // Authorize ERC20 trades by exchange
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        // Deploy OrderMatcher
+        orderMatcher = await OrderMatcherContract.deployFrom0xArtifactAsync(
+            artifacts.OrderMatcher,
+            provider,
+            txDefaults,
+            exchange.address,
+        );
+        // Set default addresses
+        defaultERC20MakerAssetAddress = erc20TokenA.address;
+        defaultERC20TakerAssetAddress = erc20TokenB.address;
+        leftMakerAssetData = assetDataUtils.encodeERC20AssetData(defaultERC20MakerAssetAddress);
+        leftTakerAssetData = assetDataUtils.encodeERC20AssetData(defaultERC20TakerAssetAddress);
+        // Set OrderMatcher balances and allowances
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc20TokenA.setBalance.sendTransactionAsync(orderMatcher.address, constants.INITIAL_ERC20_BALANCE, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc20TokenB.setBalance.sendTransactionAsync(orderMatcher.address, constants.INITIAL_ERC20_BALANCE, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await orderMatcher.approveAssetProxy.sendTransactionAsync(
+                leftMakerAssetData,
+                constants.INITIAL_ERC20_ALLOWANCE,
+            ),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await orderMatcher.approveAssetProxy.sendTransactionAsync(
+                leftTakerAssetData,
+                constants.INITIAL_ERC20_ALLOWANCE,
+            ),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        // Create default order parameters
+        const defaultOrderParamsLeft = {
+            ...constants.STATIC_ORDER_PARAMS,
+            makerAddress: makerAddressLeft,
+            exchangeAddress: exchange.address,
+            makerAssetData: leftMakerAssetData,
+            takerAssetData: leftTakerAssetData,
+            feeRecipientAddress: feeRecipientAddressLeft,
+            makerFee: constants.ZERO_AMOUNT,
+            takerFee: constants.ZERO_AMOUNT,
+        };
+        const defaultOrderParamsRight = {
+            ...constants.STATIC_ORDER_PARAMS,
+            makerAddress: makerAddressRight,
+            exchangeAddress: exchange.address,
+            makerAssetData: leftTakerAssetData,
+            takerAssetData: leftMakerAssetData,
+            feeRecipientAddress: feeRecipientAddressRight,
+            makerFee: constants.ZERO_AMOUNT,
+            takerFee: constants.ZERO_AMOUNT,
+        };
+        const privateKeyLeft = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddressLeft)];
+        orderFactoryLeft = new OrderFactory(privateKeyLeft, defaultOrderParamsLeft);
+        const privateKeyRight = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddressRight)];
+        orderFactoryRight = new OrderFactory(privateKeyRight, defaultOrderParamsRight);
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('constructor', () => {
+        it('should revert if assetProxy is unregistered', async () => {
+            const exchangeInstance = await ExchangeContract.deployFrom0xArtifactAsync(
+                protocolArtifacts.Exchange,
+                provider,
+                txDefaults,
+                constants.NULL_BYTES,
+            );
+            return expectContractCreationFailedAsync(
+                (OrderMatcherContract.deployFrom0xArtifactAsync(
+                    artifacts.OrderMatcher,
+                    provider,
+                    txDefaults,
+                    exchangeInstance.address,
+                ) as any) as sendTransactionResult,
+                RevertReason.UnregisteredAssetProxy,
+            );
+        });
+    });
+    describe('matchOrders', () => {
+        beforeEach(async () => {
+            erc20BalancesByOwner = await erc20Wrapper.getBalancesAsync();
+        });
+        it('should revert if not called by owner', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(2), 18),
+            });
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await expectTransactionFailedAsync(
+                web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: takerAddress,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                RevertReason.OnlyContractOwner,
+            );
+        });
+        it('should transfer the correct amounts when orders completely fill each other', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(2), 18),
+            });
+            // Match signedOrderLeft with signedOrderRight
+            const expectedTransferAmounts = {
+                // Left Maker
+                amountSoldByLeftMaker: signedOrderLeft.makerAssetAmount,
+                amountBoughtByLeftMaker: signedOrderLeft.takerAssetAmount,
+                // Right Maker
+                amountSoldByRightMaker: signedOrderRight.makerAssetAmount,
+                amountBoughtByRightMaker: signedOrderRight.takerAssetAmount,
+                // Taker
+                leftMakerAssetSpreadAmount: signedOrderLeft.makerAssetAmount.minus(signedOrderRight.takerAssetAmount),
+            };
+            const initialLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const newLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const newErc20Balances = await erc20Wrapper.getBalancesAsync();
+            expect(newErc20Balances[makerAddressLeft][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20MakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20TakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByRightMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressLeft][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20TakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20MakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByRightMaker,
+                ),
+            );
+            expect(newLeftMakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftMakerAssetTakerBalance.plus(expectedTransferAmounts.leftMakerAssetSpreadAmount),
+            );
+        });
+        it('should transfer the correct amounts when orders completely fill each other and taker doesnt take a profit', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+            });
+            // Match signedOrderLeft with signedOrderRight
+            const expectedTransferAmounts = {
+                // Left Maker
+                amountSoldByLeftMaker: signedOrderLeft.makerAssetAmount,
+                amountBoughtByLeftMaker: signedOrderLeft.takerAssetAmount,
+                // Right Maker
+                amountSoldByRightMaker: signedOrderRight.makerAssetAmount,
+                amountBoughtByRightMaker: signedOrderRight.takerAssetAmount,
+            };
+            const initialLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const newLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const newErc20Balances = await erc20Wrapper.getBalancesAsync();
+            expect(newErc20Balances[makerAddressLeft][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20MakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20TakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByRightMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressLeft][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20TakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20MakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByRightMaker,
+                ),
+            );
+            expect(newLeftMakerAssetTakerBalance).to.be.bignumber.equal(initialLeftMakerAssetTakerBalance);
+        });
+        it('should transfer the correct amounts when left order is completely filled and right order would be partially filled', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(20), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(4), 18),
+            });
+            // Match signedOrderLeft with signedOrderRight
+            const expectedTransferAmounts = {
+                // Left Maker
+                amountSoldByLeftMaker: signedOrderLeft.makerAssetAmount,
+                amountBoughtByLeftMaker: signedOrderLeft.takerAssetAmount,
+                // Right Maker
+                amountSoldByRightMaker: signedOrderRight.makerAssetAmount,
+                amountBoughtByRightMaker: signedOrderRight.takerAssetAmount,
+                // Taker
+                leftMakerAssetSpreadAmount: signedOrderLeft.makerAssetAmount.minus(signedOrderRight.takerAssetAmount),
+                leftTakerAssetSpreadAmount: signedOrderRight.makerAssetAmount.minus(signedOrderLeft.takerAssetAmount),
+            };
+            const initialLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const initialLeftTakerAssetTakerBalance = await erc20TokenB.balanceOf.callAsync(orderMatcher.address);
+            // Match signedOrderLeft with signedOrderRight
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const newLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const newLeftTakerAssetTakerBalance = await erc20TokenB.balanceOf.callAsync(orderMatcher.address);
+            const newErc20Balances = await erc20Wrapper.getBalancesAsync();
+            expect(newErc20Balances[makerAddressLeft][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20MakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20TakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByRightMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressLeft][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20TakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20MakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByRightMaker,
+                ),
+            );
+            expect(newLeftMakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftMakerAssetTakerBalance.plus(expectedTransferAmounts.leftMakerAssetSpreadAmount),
+            );
+            expect(newLeftTakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftTakerAssetTakerBalance.plus(expectedTransferAmounts.leftTakerAssetSpreadAmount),
+            );
+        });
+        it('should not call fillOrder when rightOrder is completely filled after matchOrders call and orders were never partially filled', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(2), 18),
+            });
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            const logDecoder = new LogDecoder(web3Wrapper, { ...artifacts, ...tokenArtifacts, ...protocolArtifacts });
+            const txReceipt = await logDecoder.getTxWithDecodedLogsAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+            );
+            const fillLogs = _.filter(
+                txReceipt.logs,
+                log => (log as LogWithDecodedArgs<ExchangeFillEventArgs>).event === 'Fill',
+            );
+            // Only 2 Fill logs should exist for `matchOrders` call. `fillOrder` should not have been called and should not have emitted a Fill event.
+            expect(fillLogs.length).to.be.equal(2);
+        });
+        it('should not call fillOrder when rightOrder is completely filled after matchOrders call and orders were initially partially filled', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(2), 18),
+            });
+            await exchangeWrapper.fillOrderAsync(signedOrderLeft, takerAddress, {
+                takerAssetFillAmount: signedOrderLeft.takerAssetAmount.dividedToIntegerBy(5),
+            });
+            await exchangeWrapper.fillOrderAsync(signedOrderRight, takerAddress, {
+                takerAssetFillAmount: signedOrderRight.takerAssetAmount.dividedToIntegerBy(5),
+            });
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            const logDecoder = new LogDecoder(web3Wrapper, { ...artifacts, ...tokenArtifacts, ...protocolArtifacts });
+            const txReceipt = await logDecoder.getTxWithDecodedLogsAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+            );
+            const fillLogs = _.filter(
+                txReceipt.logs,
+                log => (log as LogWithDecodedArgs<ExchangeFillEventArgs>).event === 'Fill',
+            );
+            // Only 2 Fill logs should exist for `matchOrders` call. `fillOrder` should not have been called and should not have emitted a Fill event.
+            expect(fillLogs.length).to.be.equal(2);
+        });
+        it('should only take a spread in rightMakerAsset if entire leftMakerAssetSpread amount can be used to fill rightOrder after matchOrders call', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(0.9), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(100), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(990), 18),
+            });
+            const initialLeftMakerAssetSpreadAmount = Web3Wrapper.toBaseUnitAmount(new BigNumber(1.09), 18);
+            const leftTakerAssetSpreadAmount = initialLeftMakerAssetSpreadAmount
+                .times(signedOrderRight.makerAssetAmount)
+                .dividedToIntegerBy(signedOrderRight.takerAssetAmount);
+            // Match signedOrderLeft with signedOrderRight
+            const expectedTransferAmounts = {
+                // Left Maker
+                amountSoldByLeftMaker: signedOrderLeft.makerAssetAmount,
+                amountBoughtByLeftMaker: signedOrderLeft.takerAssetAmount,
+                // Right Maker
+                amountSoldByRightMaker: signedOrderLeft.takerAssetAmount.plus(leftTakerAssetSpreadAmount),
+                amountBoughtByRightMaker: signedOrderLeft.makerAssetAmount,
+                // Taker
+                leftMakerAssetSpreadAmount: constants.ZERO_AMOUNT,
+                leftTakerAssetSpreadAmount,
+            };
+            const initialLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const initialLeftTakerAssetTakerBalance = await erc20TokenB.balanceOf.callAsync(orderMatcher.address);
+            // Match signedOrderLeft with signedOrderRight
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const newLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const newLeftTakerAssetTakerBalance = await erc20TokenB.balanceOf.callAsync(orderMatcher.address);
+            const newErc20Balances = await erc20Wrapper.getBalancesAsync();
+            expect(newErc20Balances[makerAddressLeft][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20MakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20TakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByRightMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressLeft][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20TakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20MakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByRightMaker,
+                ),
+            );
+            expect(newLeftMakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftMakerAssetTakerBalance.plus(expectedTransferAmounts.leftMakerAssetSpreadAmount),
+            );
+            expect(newLeftTakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftTakerAssetTakerBalance.plus(expectedTransferAmounts.leftTakerAssetSpreadAmount),
+            );
+        });
+        it("should succeed if rightOrder's makerAssetData and takerAssetData are not provided", async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(20), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(4), 18),
+            });
+            // Match signedOrderLeft with signedOrderRight
+            const expectedTransferAmounts = {
+                // Left Maker
+                amountSoldByLeftMaker: signedOrderLeft.makerAssetAmount,
+                amountBoughtByLeftMaker: signedOrderLeft.takerAssetAmount,
+                // Right Maker
+                amountSoldByRightMaker: signedOrderRight.makerAssetAmount,
+                amountBoughtByRightMaker: signedOrderRight.takerAssetAmount,
+                // Taker
+                leftMakerAssetSpreadAmount: signedOrderLeft.makerAssetAmount.minus(signedOrderRight.takerAssetAmount),
+                leftTakerAssetSpreadAmount: signedOrderRight.makerAssetAmount.minus(signedOrderLeft.takerAssetAmount),
+            };
+            const initialLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const initialLeftTakerAssetTakerBalance = await erc20TokenB.balanceOf.callAsync(orderMatcher.address);
+            // Match signedOrderLeft with signedOrderRight
+            signedOrderRight.makerAssetData = constants.NULL_BYTES;
+            signedOrderRight.takerAssetData = constants.NULL_BYTES;
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const newLeftMakerAssetTakerBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            const newLeftTakerAssetTakerBalance = await erc20TokenB.balanceOf.callAsync(orderMatcher.address);
+            const newErc20Balances = await erc20Wrapper.getBalancesAsync();
+            expect(newErc20Balances[makerAddressLeft][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20MakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20TakerAssetAddress].minus(
+                    expectedTransferAmounts.amountSoldByRightMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressLeft][defaultERC20TakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressLeft][defaultERC20TakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByLeftMaker,
+                ),
+            );
+            expect(newErc20Balances[makerAddressRight][defaultERC20MakerAssetAddress]).to.be.bignumber.equal(
+                erc20BalancesByOwner[makerAddressRight][defaultERC20MakerAssetAddress].plus(
+                    expectedTransferAmounts.amountBoughtByRightMaker,
+                ),
+            );
+            expect(newLeftMakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftMakerAssetTakerBalance.plus(expectedTransferAmounts.leftMakerAssetSpreadAmount),
+            );
+            expect(newLeftTakerAssetTakerBalance).to.be.bignumber.equal(
+                initialLeftTakerAssetTakerBalance.plus(expectedTransferAmounts.leftTakerAssetSpreadAmount),
+            );
+        });
+        it('should revert with the correct reason if matchOrders call reverts', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+            });
+            signedOrderRight.signature = `0xff${signedOrderRight.signature.slice(4)}`;
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await expectTransactionFailedAsync(
+                web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                RevertReason.InvalidOrderSignature,
+            );
+        });
+        it('should revert with the correct reason if fillOrder call reverts', async () => {
+            // Create orders to match
+            const signedOrderLeft = await orderFactoryLeft.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
+            });
+            const signedOrderRight = await orderFactoryRight.newSignedOrderAsync({
+                makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(20), 18),
+                takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(4), 18),
+            });
+            // Matcher will not have enough allowance to fill rightOrder
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await orderMatcher.approveAssetProxy.sendTransactionAsync(leftMakerAssetData, constants.ZERO_AMOUNT, {
+                    from: owner,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const data = exchange.matchOrders.getABIEncodedTransactionData(
+                signedOrderLeft,
+                signedOrderRight,
+                signedOrderLeft.signature,
+                signedOrderRight.signature,
+            );
+            await expectTransactionFailedAsync(
+                web3Wrapper.sendTransactionAsync({
+                    data,
+                    to: orderMatcher.address,
+                    from: owner,
+                    gas: constants.MAX_MATCH_ORDERS_GAS,
+                }),
+                RevertReason.TransferFailed,
+            );
+        });
+    });
+    describe('withdrawAsset', () => {
+        it('should allow owner to withdraw ERC20 tokens', async () => {
+            const erc20AWithdrawAmount = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            expect(erc20AWithdrawAmount).to.be.bignumber.gt(constants.ZERO_AMOUNT);
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await orderMatcher.withdrawAsset.sendTransactionAsync(leftMakerAssetData, erc20AWithdrawAmount, {
+                    from: owner,
+                }),
+            );
+            const newBalance = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            expect(newBalance).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+        });
+        it('should allow owner to withdraw ERC721 tokens', async () => {
+            const erc721Token = await DummyERC721TokenContract.deployFrom0xArtifactAsync(
+                tokenArtifacts.DummyERC721Token,
+                provider,
+                txDefaults,
+                constants.DUMMY_TOKEN_NAME,
+                constants.DUMMY_TOKEN_SYMBOL,
+            );
+            const tokenId = new BigNumber(1);
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await erc721Token.mint.sendTransactionAsync(orderMatcher.address, tokenId, { from: owner }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const assetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, tokenId);
+            const withdrawAmount = new BigNumber(1);
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await orderMatcher.withdrawAsset.sendTransactionAsync(assetData, withdrawAmount, { from: owner }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const erc721Owner = await erc721Token.ownerOf.callAsync(tokenId);
+            expect(erc721Owner).to.be.equal(owner);
+        });
+        it('should revert if not called by owner', async () => {
+            const erc20AWithdrawAmount = await erc20TokenA.balanceOf.callAsync(orderMatcher.address);
+            expect(erc20AWithdrawAmount).to.be.bignumber.gt(constants.ZERO_AMOUNT);
+            await expectTransactionFailedAsync(
+                orderMatcher.withdrawAsset.sendTransactionAsync(leftMakerAssetData, erc20AWithdrawAmount, {
+                    from: takerAddress,
+                }),
+                RevertReason.OnlyContractOwner,
+            );
+        });
+    });
+    describe('approveAssetProxy', () => {
+        it('should be able to set an allowance for ERC20 tokens', async () => {
+            const allowance = new BigNumber(55465465426546);
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await orderMatcher.approveAssetProxy.sendTransactionAsync(leftMakerAssetData, allowance, {
+                    from: owner,
+                }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const newAllowance = await erc20TokenA.allowance.callAsync(orderMatcher.address, erc20Proxy.address);
+            expect(newAllowance).to.be.bignumber.equal(allowance);
+        });
+        it('should be able to approve an ERC721 token by passing in allowance = 1', async () => {
+            const erc721Token = await DummyERC721TokenContract.deployFrom0xArtifactAsync(
+                tokenArtifacts.DummyERC721Token,
+                provider,
+                txDefaults,
+                constants.DUMMY_TOKEN_NAME,
+                constants.DUMMY_TOKEN_SYMBOL,
+            );
+            const assetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, constants.ZERO_AMOUNT);
+            const allowance = new BigNumber(1);
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await orderMatcher.approveAssetProxy.sendTransactionAsync(assetData, allowance, { from: owner }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const isApproved = await erc721Token.isApprovedForAll.callAsync(orderMatcher.address, erc721Proxy.address);
+            expect(isApproved).to.be.equal(true);
+        });
+        it('should be able to approve an ERC721 token by passing in allowance > 1', async () => {
+            const erc721Token = await DummyERC721TokenContract.deployFrom0xArtifactAsync(
+                tokenArtifacts.DummyERC721Token,
+                provider,
+                txDefaults,
+                constants.DUMMY_TOKEN_NAME,
+                constants.DUMMY_TOKEN_SYMBOL,
+            );
+            const assetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, constants.ZERO_AMOUNT);
+            const allowance = new BigNumber(2);
+            await web3Wrapper.awaitTransactionSuccessAsync(
+                await orderMatcher.approveAssetProxy.sendTransactionAsync(assetData, allowance, { from: owner }),
+                constants.AWAIT_TRANSACTION_MINED_MS,
+            );
+            const isApproved = await erc721Token.isApprovedForAll.callAsync(orderMatcher.address, erc721Proxy.address);
+            expect(isApproved).to.be.equal(true);
+        });
+        it('should revert if not called by owner', async () => {
+            const approval = new BigNumber(1);
+            await expectTransactionFailedAsync(
+                orderMatcher.approveAssetProxy.sendTransactionAsync(leftMakerAssetData, approval, {
+                    from: takerAddress,
+                }),
+                RevertReason.OnlyContractOwner,
+            );
+        });
+    });
+});
+// tslint:disable:max-file-line-count
+// tslint:enable:no-unnecessary-type-assertion

contracts/extensions/test/extensions/order_validator.ts

@@ -1,3 +1,22 @@
+import {
+    artifacts as protocolArtifacts,
+    ERC20ProxyContract,
+    ERC20Wrapper,
+    ERC721ProxyContract,
+    ERC721Wrapper,
+    ExchangeContract,
+    ExchangeWrapper,
+} from '@0x/contracts-protocol';
+import {
+    chaiSetup,
+    constants,
+    OrderFactory,
+    OrderStatus,
+    provider,
+    txDefaults,
+    web3Wrapper,
+} from '@0x/contracts-test-utils';
+import { DummyERC20TokenContract, DummyERC721TokenContract } from '@0x/contracts-tokens';
 import { BlockchainLifecycle } from '@0x/dev-utils';
 import { assetDataUtils, orderHashUtils } from '@0x/order-utils';
 import { SignedOrder } from '@0x/types';
@@ -5,21 +24,8 @@ import { BigNumber } from '@0x/utils';
 import * as chai from 'chai';
 import * as _ from 'lodash';
 
-import { DummyERC20TokenContract } from '../../generated-wrappers/dummy_erc20_token';
-import { DummyERC721TokenContract } from '../../generated-wrappers/dummy_erc721_token';
-import { ERC20ProxyContract } from '../../generated-wrappers/erc20_proxy';
-import { ERC721ProxyContract } from '../../generated-wrappers/erc721_proxy';
-import { ExchangeContract } from '../../generated-wrappers/exchange';
 import { OrderValidatorContract } from '../../generated-wrappers/order_validator';
-import { artifacts } from '../../src/artifacts';
+import { artifacts } from '../../src/artifacts/index';
-import { chaiSetup } from '../utils/chai_setup';
-import { constants } from '../utils/constants';
-import { ERC20Wrapper } from '../utils/erc20_wrapper';
-import { ERC721Wrapper } from '../utils/erc721_wrapper';
-import { ExchangeWrapper } from '../utils/exchange_wrapper';
-import { OrderFactory } from '../utils/order_factory';
-import { OrderStatus } from '../utils/types';
-import { provider, txDefaults, web3Wrapper } from '../utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -75,7 +81,7 @@ describe('OrderValidator', () => {
 
         const zrxAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
         exchange = await ExchangeContract.deployFrom0xArtifactAsync(
-            artifacts.Exchange,
+            protocolArtifacts.Exchange,
             provider,
             txDefaults,
             zrxAssetData,

contracts/extensions/test/global_hooks.ts

@@ -0,0 +1,17 @@
+import { env, EnvVars } from '@0x/dev-utils';
+
+import { coverage, profiler, provider } from '@0x/contracts-test-utils';
+before('start web3 provider', () => {
+    provider.start();
+});
+after('generate coverage report', async () => {
+    if (env.parseBoolean(EnvVars.SolidityCoverage)) {
+        const coverageSubprovider = coverage.getCoverageSubproviderSingleton();
+        await coverageSubprovider.writeCoverageAsync();
+    }
+    if (env.parseBoolean(EnvVars.SolidityProfiler)) {
+        const profilerSubprovider = profiler.getProfilerSubproviderSingleton();
+        await profilerSubprovider.writeProfilerOutputAsync();
+    }
+    provider.stop();
+});

contracts/extensions/test/utils/balance_threshold_wrapper.ts

@@ -0,0 +1,283 @@
+import { artifacts as protocolArtifacts, ExchangeContract } from '@0x/contracts-protocol';
+import {
+    FillResults,
+    formatters,
+    LogDecoder,
+    OrderInfo,
+    orderUtils,
+    TransactionFactory,
+} from '@0x/contracts-test-utils';
+import { artifacts as tokensArtifacts } from '@0x/contracts-tokens';
+import { SignedOrder } from '@0x/types';
+import { BigNumber } from '@0x/utils';
+import { Web3Wrapper } from '@0x/web3-wrapper';
+import { Provider, TransactionReceiptWithDecodedLogs } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { BalanceThresholdFilterContract } from '../../generated-wrappers/balance_threshold_filter';
+import { artifacts } from '../../src/artifacts';
+
+export class BalanceThresholdWrapper {
+    private readonly _balanceThresholdFilter: BalanceThresholdFilterContract;
+    private readonly _signerTransactionFactory: TransactionFactory;
+    private readonly _exchange: ExchangeContract;
+    private readonly _web3Wrapper: Web3Wrapper;
+    private readonly _logDecoder: LogDecoder;
+    constructor(
+        balanceThresholdFilter: BalanceThresholdFilterContract,
+        exchangeContract: ExchangeContract,
+        signerTransactionFactory: TransactionFactory,
+        provider: Provider,
+    ) {
+        this._balanceThresholdFilter = balanceThresholdFilter;
+        this._exchange = exchangeContract;
+        this._signerTransactionFactory = signerTransactionFactory;
+        this._web3Wrapper = new Web3Wrapper(provider);
+        this._logDecoder = new LogDecoder(this._web3Wrapper, {
+            ...artifacts,
+            ...tokensArtifacts,
+            ...protocolArtifacts,
+        });
+    }
+    public async fillOrderAsync(
+        signedOrder: SignedOrder,
+        from: string,
+        opts: { takerAssetFillAmount?: BigNumber } = {},
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
+        const data = this._exchange.fillOrder.getABIEncodedTransactionData(
+            params.order,
+            params.takerAssetFillAmount,
+            params.signature,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async fillOrKillOrderAsync(
+        signedOrder: SignedOrder,
+        from: string,
+        opts: { takerAssetFillAmount?: BigNumber } = {},
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
+        const data = this._exchange.fillOrKillOrder.getABIEncodedTransactionData(
+            params.order,
+            params.takerAssetFillAmount,
+            params.signature,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async fillOrderNoThrowAsync(
+        signedOrder: SignedOrder,
+        from: string,
+        opts: { takerAssetFillAmount?: BigNumber; gas?: number } = {},
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
+        const data = this._exchange.fillOrderNoThrow.getABIEncodedTransactionData(
+            params.order,
+            params.takerAssetFillAmount,
+            params.signature,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from, opts.gas);
+        return txReceipt;
+    }
+    public async batchFillOrdersAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { takerAssetFillAmounts?: BigNumber[] } = {},
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createBatchFill(orders, opts.takerAssetFillAmounts);
+        const data = this._exchange.batchFillOrders.getABIEncodedTransactionData(
+            params.orders,
+            params.takerAssetFillAmounts,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async batchFillOrKillOrdersAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { takerAssetFillAmounts?: BigNumber[] } = {},
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createBatchFill(orders, opts.takerAssetFillAmounts);
+        const data = this._exchange.batchFillOrKillOrders.getABIEncodedTransactionData(
+            params.orders,
+            params.takerAssetFillAmounts,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async batchFillOrdersNoThrowAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { takerAssetFillAmounts?: BigNumber[]; gas?: number } = {},
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createBatchFill(orders, opts.takerAssetFillAmounts);
+        const data = this._exchange.batchFillOrKillOrders.getABIEncodedTransactionData(
+            params.orders,
+            params.takerAssetFillAmounts,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from, opts.gas);
+        return txReceipt;
+    }
+    public async marketSellOrdersAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { takerAssetFillAmount: BigNumber },
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createMarketSellOrders(orders, opts.takerAssetFillAmount);
+        const data = this._exchange.marketSellOrders.getABIEncodedTransactionData(
+            params.orders,
+            params.takerAssetFillAmount,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async marketSellOrdersNoThrowAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { takerAssetFillAmount: BigNumber; gas?: number },
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createMarketSellOrders(orders, opts.takerAssetFillAmount);
+        const data = this._exchange.marketSellOrdersNoThrow.getABIEncodedTransactionData(
+            params.orders,
+            params.takerAssetFillAmount,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from, opts.gas);
+        return txReceipt;
+    }
+    public async marketBuyOrdersAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { makerAssetFillAmount: BigNumber },
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createMarketBuyOrders(orders, opts.makerAssetFillAmount);
+        const data = this._exchange.marketBuyOrders.getABIEncodedTransactionData(
+            params.orders,
+            params.makerAssetFillAmount,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async marketBuyOrdersNoThrowAsync(
+        orders: SignedOrder[],
+        from: string,
+        opts: { makerAssetFillAmount: BigNumber; gas?: number },
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createMarketBuyOrders(orders, opts.makerAssetFillAmount);
+        const data = this._exchange.marketBuyOrdersNoThrow.getABIEncodedTransactionData(
+            params.orders,
+            params.makerAssetFillAmount,
+            params.signatures,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from, opts.gas);
+        return txReceipt;
+    }
+    public async cancelOrderAsync(signedOrder: SignedOrder, from: string): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = orderUtils.createCancel(signedOrder);
+        const data = this._exchange.cancelOrder.getABIEncodedTransactionData(params.order);
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async batchCancelOrdersAsync(
+        orders: SignedOrder[],
+        from: string,
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = formatters.createBatchCancel(orders);
+        const data = this._exchange.batchCancelOrders.getABIEncodedTransactionData(params.orders);
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async cancelOrdersUpToAsync(salt: BigNumber, from: string): Promise<TransactionReceiptWithDecodedLogs> {
+        const data = this._exchange.cancelOrdersUpTo.getABIEncodedTransactionData(salt);
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async getTakerAssetFilledAmountAsync(orderHashHex: string): Promise<BigNumber> {
+        const filledAmount = await this._exchange.filled.callAsync(orderHashHex);
+        return filledAmount;
+    }
+    public async isCancelledAsync(orderHashHex: string): Promise<boolean> {
+        const isCancelled = await this._exchange.cancelled.callAsync(orderHashHex);
+        return isCancelled;
+    }
+    public async getOrderEpochAsync(makerAddress: string, senderAddress: string): Promise<BigNumber> {
+        const orderEpoch = await this._exchange.orderEpoch.callAsync(makerAddress, senderAddress);
+        return orderEpoch;
+    }
+    public async getOrderInfoAsync(signedOrder: SignedOrder): Promise<OrderInfo> {
+        const orderInfo = await this._exchange.getOrderInfo.callAsync(signedOrder);
+        return orderInfo;
+    }
+    public async getOrdersInfoAsync(signedOrders: SignedOrder[]): Promise<OrderInfo[]> {
+        const ordersInfo = (await this._exchange.getOrdersInfo.callAsync(signedOrders)) as OrderInfo[];
+        return ordersInfo;
+    }
+    public async matchOrdersAsync(
+        signedOrderLeft: SignedOrder,
+        signedOrderRight: SignedOrder,
+        from: string,
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = orderUtils.createMatchOrders(signedOrderLeft, signedOrderRight);
+        const data = await this._exchange.matchOrders.getABIEncodedTransactionData(
+            params.left,
+            params.right,
+            params.leftSignature,
+            params.rightSignature,
+        );
+        const txReceipt = this._executeTransactionAsync(data, from);
+        return txReceipt;
+    }
+    public async getFillOrderResultsAsync(
+        signedOrder: SignedOrder,
+        from: string,
+        opts: { takerAssetFillAmount?: BigNumber } = {},
+    ): Promise<FillResults> {
+        const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
+        const fillResults = await this._exchange.fillOrder.callAsync(
+            params.order,
+            params.takerAssetFillAmount,
+            params.signature,
+            { from },
+        );
+        return fillResults;
+    }
+    public abiEncodeFillOrder(signedOrder: SignedOrder, opts: { takerAssetFillAmount?: BigNumber } = {}): string {
+        const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
+        const data = this._exchange.fillOrder.getABIEncodedTransactionData(
+            params.order,
+            params.takerAssetFillAmount,
+            params.signature,
+        );
+        return data;
+    }
+    public getBalanceThresholdAddress(): string {
+        return this._balanceThresholdFilter.address;
+    }
+    public getExchangeAddress(): string {
+        return this._exchange.address;
+    }
+    private async _executeTransactionAsync(
+        abiEncodedExchangeTxData: string,
+        from: string,
+        gas?: number,
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const signedExchangeTx = this._signerTransactionFactory.newSignedTransaction(abiEncodedExchangeTxData);
+        const txOpts = _.isUndefined(gas) ? { from } : { from, gas };
+        const txHash = await this._balanceThresholdFilter.executeTransaction.sendTransactionAsync(
+            signedExchangeTx.salt,
+            signedExchangeTx.signerAddress,
+            signedExchangeTx.data,
+            signedExchangeTx.signature,
+            txOpts,
+        );
+        const txReceipt = await this._logDecoder.getTxWithDecodedLogsAsync(txHash);
+        return txReceipt;
+    }
+}

contracts/extensions/test/utils/forwarder_wrapper.ts

@@ -1,3 +1,6 @@
+import { artifacts as protocolArtifacts } from '@0x/contracts-protocol';
+import { constants, formatters, LogDecoder, MarketSellOrders } from '@0x/contracts-test-utils';
+import { artifacts as tokensArtifacts } from '@0x/contracts-tokens';
 import { SignedOrder } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import { Web3Wrapper } from '@0x/web3-wrapper';
@@ -5,11 +8,7 @@ import { Provider, TransactionReceiptWithDecodedLogs, TxDataPayable } from 'ethe
 import * as _ from 'lodash';
 
 import { ForwarderContract } from '../../generated-wrappers/forwarder';
-
+import { artifacts } from '../../src/artifacts';
-import { constants } from './constants';
-import { formatters } from './formatters';
-import { LogDecoder } from './log_decoder';
-import { MarketSellOrders } from './types';
 
 export class ForwarderWrapper {
     private readonly _web3Wrapper: Web3Wrapper;
@@ -61,7 +60,11 @@ export class ForwarderWrapper {
     constructor(contractInstance: ForwarderContract, provider: Provider) {
         this._forwarderContract = contractInstance;
         this._web3Wrapper = new Web3Wrapper(provider);
-        this._logDecoder = new LogDecoder(this._web3Wrapper);
+        this._logDecoder = new LogDecoder(this._web3Wrapper, {
+            ...artifacts,
+            ...tokensArtifacts,
+            ...protocolArtifacts,
+        });
     }
     public async marketSellOrdersWithEthAsync(
         orders: SignedOrder[],

contracts/extensions/tsconfig.json

@@ -0,0 +1,17 @@
+{
+    "extends": "../../tsconfig",
+    "compilerOptions": {
+        "outDir": "lib",
+        "rootDir": ".",
+        "resolveJsonModule": true
+    },
+    "include": ["./src/**/*", "./test/**/*", "./generated-wrappers/**/*"],
+    "files": [
+        "./generated-artifacts/BalanceThresholdFilter.json",
+        "./generated-artifacts/DutchAuction.json",
+        "./generated-artifacts/Forwarder.json",
+        "./generated-artifacts/OrderMatcher.json",
+        "./generated-artifacts/OrderValidator.json"
+    ],
+    "exclude": ["./deploy/solc/solc_bin"]
+}

contracts/extensions/tslint.json

@@ -0,0 +1,6 @@
+{
+    "extends": ["@0x/tslint-config"],
+    "rules": {
+        "custom-no-magic-numbers": false
+    }
+}

contracts/interfaces/CHANGELOG.json

@@ -0,0 +1,11 @@
+[
+    {
+        "timestamp": 1544741676,
+        "version": "1.0.2",
+        "changes": [
+            {
+                "note": "Dependencies updated"
+            }
+        ]
+    }
+]

contracts/interfaces/CHANGELOG.md

@@ -0,0 +1,10 @@
+<!--
+changelogUtils.file is auto-generated using the monorepo-scripts package. Don't edit directly.
+Edit the package's CHANGELOG.json file only.
+-->
+
+CHANGELOG
+
+## v1.0.2 - _December 13, 2018_
+
+    * Dependencies updated

contracts/interfaces/README.md

@@ -0,0 +1,72 @@
+## Contract interfaces
+
+Smart contract interfaces of the 0x protocol.
+
+## Usage
+
+Contracts that make up and interact with version 2.0.0 of the protocol can be found in the [contracts](./contracts) directory. The contents of this directory are broken down into the following subdirectories:
+
+*   [protocol](./contracts/protocol)
+    *   This directory contains the contract interfaces that make up version 2.0.0. A full specification can be found [here](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md).
+
+## Bug bounty
+
+A bug bounty for the 2.0.0 contracts is ongoing! Instructions can be found [here](https://0xproject.com/wiki#Bug-Bounty).
+
+## Contributing
+
+We strongly recommend that the community help us make improvements and determine the future direction of the protocol. To report bugs within this package, please create an issue in this repository.
+
+For proposals regarding the 0x protocol's smart contract architecture, message format, or additional functionality, go to the [0x Improvement Proposals (ZEIPs)](https://github.com/0xProject/ZEIPs) repository and follow the contribution guidelines provided therein.
+
+Please read our [contribution guidelines](../../CONTRIBUTING.md) before getting started.
+
+### Install Dependencies
+
+If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:
+
+```bash
+yarn config set workspaces-experimental true
+```
+
+Then install dependencies
+
+```bash
+yarn install
+```
+
+### Build
+
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
+
+```bash
+PKG=@0x/contracts-interfaces yarn build
+```
+
+Or continuously rebuild on change:
+
+```bash
+PKG=@0x/contracts-interfaces yarn watch
+```
+
+### Clean
+
+```bash
+yarn clean
+```
+
+### Lint
+
+```bash
+yarn lint
+```
+
+### Run Tests
+
+```bash
+yarn test
+```
+
+#### Testing options
+
+Contracts testing options like coverage, profiling, revert traces or backing node choosing - are described [here](../TESTING.md).

contracts/interfaces/compiler.json

@@ -0,0 +1,35 @@
+{
+    "artifactsDir": "./generated-artifacts",
+    "contractsDir": "./contracts",
+    "compilerSettings": {
+        "optimizer": {
+            "enabled": true,
+            "runs": 1000000
+        },
+        "outputSelection": {
+            "*": {
+                "*": [
+                    "abi",
+                    "evm.bytecode.object",
+                    "evm.bytecode.sourceMap",
+                    "evm.deployedBytecode.object",
+                    "evm.deployedBytecode.sourceMap"
+                ]
+            }
+        }
+    },
+    "contracts": [
+        "IAssetData",
+        "IAssetProxy",
+        "IAuthorizable",
+        "IAssetProxyDispatcher",
+        "IExchange",
+        "IExchangeCore",
+        "IMatchOrders",
+        "ISignatureValidator",
+        "ITransactions",
+        "IValidator",
+        "IWallet",
+        "IWrapperFunctions"
+    ]
+}

contracts/interfaces/contracts/protocol/AssetProxy/IAssetData.sol

@@ -17,7 +17,8 @@
 */
 
 // solhint-disable
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
+pragma experimental ABIEncoderV2;
 
 
 // @dev Interface of the asset proxy's assetData.
@@ -26,15 +27,18 @@ pragma solidity 0.4.24;
 interface IAssetData {
 
     function ERC20Token(address tokenContract)
-        external
+        external;
-        pure;
     
     function ERC721Token(
         address tokenContract,
-        uint256 tokenId,
+        uint256 tokenId
-        bytes receiverData
     )
-        external
+        external;
-        pure;
+
+    function MultiAsset(
+        uint256[] amounts,
+        bytes[] nestedAssetData
+    )
+        external;
     
 }

contracts/interfaces/contracts/protocol/AssetProxy/IAssetProxy.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 import "./IAuthorizable.sol";
 

contracts/interfaces/contracts/protocol/AssetProxy/IAuthorizable.sol

@@ -16,9 +16,9 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
-import "../../../utils/Ownable/IOwnable.sol";
+import "@0x/contracts-utils/contracts/utils/Ownable/IOwnable.sol";
 
 
 contract IAuthorizable is

contracts/interfaces/contracts/protocol/Exchange/IAssetProxyDispatcher.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract IAssetProxyDispatcher {

contracts/interfaces/contracts/protocol/Exchange/IExchange.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
 import "./IExchangeCore.sol";

contracts/interfaces/contracts/protocol/Exchange/IExchangeCore.sol

@@ -16,11 +16,11 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
 
 
 contract IExchangeCore {

contracts/interfaces/contracts/protocol/Exchange/IMatchOrders.sol

@@ -15,11 +15,11 @@
   limitations under the License.
 
 */
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
 
 
 contract IMatchOrders {

contracts/interfaces/contracts/protocol/Exchange/ISignatureValidator.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract ISignatureValidator {

contracts/interfaces/contracts/protocol/Exchange/ITransactions.sol

@@ -15,7 +15,7 @@
   limitations under the License.
 
 */
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract ITransactions {

contracts/interfaces/contracts/protocol/Exchange/IValidator.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract IValidator {

contracts/interfaces/contracts/protocol/Exchange/IWallet.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
 
 contract IWallet {

contracts/interfaces/contracts/protocol/Exchange/IWrapperFunctions.sol

@@ -16,11 +16,11 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
-import "../libs/LibOrder.sol";
+import "@0x/contracts-libs/contracts/libs/LibOrder.sol";
-import "../libs/LibFillResults.sol";
+import "@0x/contracts-libs/contracts/libs/LibFillResults.sol";
 
 
 contract IWrapperFunctions {

contracts/interfaces/package.json

@@ -0,0 +1,57 @@
+{
+    "name": "@0x/contracts-interfaces",
+    "version": "1.0.2",
+    "engines": {
+        "node": ">=6.12"
+    },
+    "description": "Smart contract interfaces of 0x protocol",
+    "main": "lib/src/index.js",
+    "scripts": {
+        "build": "yarn pre_build && tsc -b",
+        "build:ci": "yarn build",
+        "pre_build": "run-s compile generate_contract_wrappers",
+        "compile": "sol-compiler",
+        "watch": "sol-compiler -w",
+        "clean": "shx rm -rf lib generated-artifacts generated-wrappers",
+        "generate_contract_wrappers": "abi-gen --abis  ${npm_package_config_abis} --template ../../node_modules/@0x/abi-gen-templates/contract.handlebars --partials '../../node_modules/@0x/abi-gen-templates/partials/**/*.handlebars' --output generated-wrappers --backend ethers",
+        "lint": "tslint --format stylish --project . --exclude ./generated-wrappers/**/* --exclude ./generated-artifacts/**/* --exclude **/lib/**/* && yarn lint-contracts",
+        "lint-contracts": "solhint -c ../.solhint.json contracts/**/**/**/**/*.sol"
+    },
+    "config": {
+        "abis": "generated-artifacts/@(IAssetData|IAssetProxy|IAuthorizable|IAssetProxyDispatcher|IExchange|IExchangeCore|IMatchOrders|ISignatureValidator|ITransactions|IValidator|IWallet|IWrapperFunctions).json"
+    },
+    "repository": {
+        "type": "git",
+        "url": "https://github.com/0xProject/0x-monorepo.git"
+    },
+    "license": "Apache-2.0",
+    "bugs": {
+        "url": "https://github.com/0xProject/0x-monorepo/issues"
+    },
+    "homepage": "https://github.com/0xProject/0x-monorepo/contracts/interfaces/README.md",
+    "devDependencies": {
+        "@0x/abi-gen": "^1.0.19",
+        "@0x/sol-compiler": "^1.1.16",
+        "@0x/tslint-config": "^2.0.0",
+        "npm-run-all": "^4.1.2",
+        "shx": "^0.2.2",
+        "solhint": "^1.4.1",
+        "tslint": "5.11.0",
+        "typescript": "3.0.1",
+        "yargs": "^10.0.3"
+    },
+    "dependencies": {
+        "@0x/base-contract": "^3.0.10",
+        "@0x/contracts-libs": "^1.0.2",
+        "@0x/contracts-utils": "^1.0.2",
+        "@0x/types": "^1.4.1",
+        "@0x/typescript-typings": "^3.0.6",
+        "@0x/utils": "^2.0.8",
+        "@0x/web3-wrapper": "^3.2.1",
+        "ethereum-types": "^1.1.4",
+        "lodash": "^4.17.5"
+    },
+    "publishConfig": {
+        "access": "public"
+    }
+}

contracts/interfaces/src/artifacts/index.ts

@@ -0,0 +1,29 @@
+import { ContractArtifact } from 'ethereum-types';
+
+import * as IAssetData from '../../generated-artifacts/IAssetData.json';
+import * as IAssetProxy from '../../generated-artifacts/IAssetProxy.json';
+import * as IAssetProxyDispatcher from '../../generated-artifacts/IAssetProxyDispatcher.json';
+import * as IAuthorizable from '../../generated-artifacts/IAuthorizable.json';
+import * as IExchange from '../../generated-artifacts/IExchange.json';
+import * as IExchangeCore from '../../generated-artifacts/IExchangeCore.json';
+import * as IMatchOrders from '../../generated-artifacts/IMatchOrders.json';
+import * as ISignatureValidator from '../../generated-artifacts/ISignatureValidator.json';
+import * as ITransactions from '../../generated-artifacts/ITransactions.json';
+import * as IValidator from '../../generated-artifacts/IValidator.json';
+import * as IWallet from '../../generated-artifacts/IWallet.json';
+import * as IWrapperFunctions from '../../generated-artifacts/IWrapperFunctions.json';
+
+export const artifacts = {
+    IAssetProxyDispatcher: IAssetProxyDispatcher as ContractArtifact,
+    IAuthorizable: IAuthorizable as ContractArtifact,
+    IExchange: IExchange as ContractArtifact,
+    IExchangeCore: IExchangeCore as ContractArtifact,
+    IMatchOrders: IMatchOrders as ContractArtifact,
+    ISignatureValidator: ISignatureValidator as ContractArtifact,
+    ITransactions: ITransactions as ContractArtifact,
+    IWrapperFunctions: IWrapperFunctions as ContractArtifact,
+    IAssetData: IAssetData as ContractArtifact,
+    IAssetProxy: IAssetProxy as ContractArtifact,
+    IValidator: IValidator as ContractArtifact,
+    IWallet: IWallet as ContractArtifact,
+};

contracts/interfaces/src/index.ts

@@ -0,0 +1,2 @@
+export * from './artifacts';
+export * from './wrappers';

contracts/interfaces/src/wrappers/index.ts

@@ -0,0 +1,12 @@
+export * from '../../generated-wrappers/i_asset_data';
+export * from '../../generated-wrappers/i_asset_proxy';
+export * from '../../generated-wrappers/i_asset_proxy_dispatcher';
+export * from '../../generated-wrappers/i_exchange';
+export * from '../../generated-wrappers/i_exchange_core';
+export * from '../../generated-wrappers/i_match_orders';
+export * from '../../generated-wrappers/i_signature_validator';
+export * from '../../generated-wrappers/i_transactions';
+export * from '../../generated-wrappers/i_authorizable';
+export * from '../../generated-wrappers/i_wrapper_functions';
+export * from '../../generated-wrappers/i_validator';
+export * from '../../generated-wrappers/i_wallet';

contracts/interfaces/tsconfig.json

@@ -0,0 +1,24 @@
+{
+    "extends": "../../tsconfig",
+    "compilerOptions": {
+        "outDir": "lib",
+        "rootDir": ".",
+        "resolveJsonModule": true
+    },
+    "include": ["./src/**/*", "./generated-wrappers/**/*"],
+    "files": [
+        "./generated-artifacts/IAssetData.json",
+        "./generated-artifacts/IAssetProxy.json",
+        "./generated-artifacts/IAuthorizable.json",
+        "./generated-artifacts/IAssetProxyDispatcher.json",
+        "./generated-artifacts/IExchange.json",
+        "./generated-artifacts/IExchangeCore.json",
+        "./generated-artifacts/IMatchOrders.json",
+        "./generated-artifacts/ISignatureValidator.json",
+        "./generated-artifacts/ITransactions.json",
+        "./generated-artifacts/IValidator.json",
+        "./generated-artifacts/IWallet.json",
+        "./generated-artifacts/IWrapperFunctions.json"
+    ],
+    "exclude": ["./deploy/solc/solc_bin"]
+}

contracts/interfaces/tslint.json

@@ -0,0 +1,6 @@
+{
+    "extends": ["@0x/tslint-config"],
+    "rules": {
+        "custom-no-magic-numbers": false
+    }
+}

contracts/libs/CHANGELOG.json

@@ -0,0 +1,11 @@
+[
+    {
+        "timestamp": 1544741676,
+        "version": "1.0.2",
+        "changes": [
+            {
+                "note": "Dependencies updated"
+            }
+        ]
+    }
+]

contracts/libs/CHANGELOG.md

@@ -0,0 +1,10 @@
+<!--
+changelogUtils.file is auto-generated using the monorepo-scripts package. Don't edit directly.
+Edit the package's CHANGELOG.json file only.
+-->
+
+CHANGELOG
+
+## v1.0.2 - _December 13, 2018_
+
+    * Dependencies updated

contracts/libs/README.md

@@ -0,0 +1,70 @@
+## Contracts libs
+
+Smart contracts libs used in the 0x protocol.
+
+## Usage
+
+Contracts can be found in the [contracts](./contracts) directory. The contents of this directory are broken down into the following subdirectories:
+
+*   [libs](./contracts/protocol)
+    *   This directory contains the libs.
+*   [test](./contracts/test)
+    *   This directory contains mocks and other contracts that are used solely for testing contracts within the other directories.
+
+## Contributing
+
+We strongly recommend that the community help us make improvements and determine the future direction of the protocol. To report bugs within this package, please create an issue in this repository.
+
+For proposals regarding the 0x protocol's smart contract architecture, message format, or additional functionality, go to the [0x Improvement Proposals (ZEIPs)](https://github.com/0xProject/ZEIPs) repository and follow the contribution guidelines provided therein.
+
+Please read our [contribution guidelines](../../CONTRIBUTING.md) before getting started.
+
+### Install Dependencies
+
+If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:
+
+```bash
+yarn config set workspaces-experimental true
+```
+
+Then install dependencies
+
+```bash
+yarn install
+```
+
+### Build
+
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
+
+```bash
+PKG=@0x/contracts-libs yarn build
+```
+
+Or continuously rebuild on change:
+
+```bash
+PKG=@0x/contracts-libs yarn watch
+```
+
+### Clean
+
+```bash
+yarn clean
+```
+
+### Lint
+
+```bash
+yarn lint
+```
+
+### Run Tests
+
+```bash
+yarn test
+```
+
+#### Testing options
+
+Contracts testing options like coverage, profiling, revert traces or backing node choosing - are described [here](../TESTING.md).

contracts/libs/compiler.json

@@ -0,0 +1,31 @@
+{
+    "artifactsDir": "./generated-artifacts",
+    "contractsDir": "./contracts",
+    "compilerSettings": {
+        "optimizer": {
+            "enabled": true,
+            "runs": 1000000
+        },
+        "outputSelection": {
+            "*": {
+                "*": [
+                    "abi",
+                    "evm.bytecode.object",
+                    "evm.bytecode.sourceMap",
+                    "evm.deployedBytecode.object",
+                    "evm.deployedBytecode.sourceMap"
+                ]
+            }
+        }
+    },
+    "contracts": [
+        "TestLibs",
+        "LibOrder",
+        "LibMath",
+        "LibFillResults",
+        "LibAbiEncoder",
+        "LibEIP712",
+        "LibAssetProxyErrors",
+        "LibConstants"
+    ]
+}

contracts/libs/contracts/libs/LibAbiEncoder.sol

@@ -16,7 +16,7 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 pragma experimental ABIEncoderV2;
 
 import "./LibOrder.sol";

contracts/libs/contracts/libs/LibAddressArray.sol

@@ -0,0 +1,84 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
+
+
+library LibAddressArray {
+
+    /// @dev Append a new address to an array of addresses.
+    ///      The `addressArray` may need to be reallocated to make space
+    ///      for the new address. Because of this we return the resulting
+    ///      memory location of `addressArray`.
+    /// @param addressToAppend  Address to append.
+    /// @return Array of addresses: [... addressArray, addressToAppend]
+    function append(address[] memory addressArray, address addressToAppend) 
+        internal pure
+        returns (address[])
+    {
+        // Get stats on address array and free memory
+        uint256 freeMemPtr = 0;
+        uint256 addressArrayBeginPtr = 0;
+        uint256 addressArrayEndPtr = 0;
+        uint256 addressArrayLength = addressArray.length;
+        uint256 addressArrayMemSizeInBytes = 32 + (32 * addressArrayLength);
+        assembly {
+            freeMemPtr := mload(0x40)
+            addressArrayBeginPtr := addressArray
+            addressArrayEndPtr := add(addressArray, addressArrayMemSizeInBytes)
+        }
+
+        // Cases for `freeMemPtr`:
+        //  `freeMemPtr` == `addressArrayEndPtr`: Nothing occupies memory after `addressArray`
+        //  `freeMemPtr` > `addressArrayEndPtr`: Some value occupies memory after `addressArray`
+        //  `freeMemPtr` < `addressArrayEndPtr`: Memory has not been managed properly.
+        require(
+            freeMemPtr >= addressArrayEndPtr,
+            "INVALID_FREE_MEMORY_PTR"
+        );
+
+        // If free memory begins at the end of `addressArray`
+        // then we can append `addressToAppend` directly.
+        // Otherwise, we must copy the array to free memory
+        // before appending new values to it.
+        if (freeMemPtr > addressArrayEndPtr) {
+            LibBytes.memCopy(freeMemPtr, addressArrayBeginPtr, addressArrayMemSizeInBytes);
+            assembly {
+                addressArray := freeMemPtr
+                addressArrayBeginPtr := addressArray
+            }
+        }
+
+        // Append `addressToAppend`
+        addressArrayLength += 1;
+        addressArrayMemSizeInBytes += 32;
+        addressArrayEndPtr = addressArrayBeginPtr + addressArrayMemSizeInBytes;
+        freeMemPtr = addressArrayEndPtr;
+        assembly {
+            // Store new array length
+            mstore(addressArray, addressArrayLength)
+
+            // Update `freeMemPtr`
+            mstore(0x40, freeMemPtr)
+        }
+        addressArray[addressArrayLength - 1] = addressToAppend;
+        return addressArray;
+    }
+}