Smart contract components of 0x protocol

Usage no npm install needed!

<script type="module">
  import 0xContractsProtocol from 'https://cdn.skypack.dev/@0x/contracts-protocol';



Smart contracts that implement the 0x protocol. Addresses of the deployed contracts can be found in the 0x wiki or the CHANGELOG of this package.


Contracts that make up and interact with version 2.0.0 of the protocol can be found in the contracts directory. The contents of this directory are broken down into the following subdirectories:

  • protocol
    • This directory contains the contracts that make up version 2.0.0. A full specification can be found here.
  • test
    • This directory contains mocks and other contracts that are used solely for testing contracts within the other directories.

Bug bounty

A bug bounty for the 2.0.0 contracts is ongoing! Instructions can be found here.


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) repository and follow the contribution guidelines provided therein.

Please read our contribution guidelines before getting started.

Install Dependencies

If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:

yarn config set workspaces-experimental true

Then install dependencies

yarn install


To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:

PKG=@0x/contracts-protocol yarn build

Or continuously rebuild on change:

PKG=@0x/contracts-protocol yarn watch


yarn clean


yarn lint

Run Tests

yarn test

Testing options

Contracts testing options like coverage, profiling, revert traces or backing node choosing - are described here.