openzeppelin-contracts

OpenZeppelin Contracts is a library for secure smart contract development.

OpenZeppelin/openzeppelin-contracts https://openzeppelin.com/contracts
starsStars 8900
forksForks 3850
watchersWatchers 8900
current-versionCurrent version v3.3.0
total-releasesTotal releases 44
open_issues_countOpen issues 102
dateFirst release 2017-03-09
dateLatest release 2020-11-27
updateLast update 2020-12-23

A library for secure smart contract development. Build on a solid foundation of community-vetted code.

Overview

Installation

$ npm install @openzeppelin/contracts

OpenZeppelin Contracts features a

Usage

Once installed, you can use the contracts in the library by importing them:

pragma solidity ^0.6.0;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";

contract MyCollectible is ERC721 {
    constructor() ERC721("MyCollectible", "MCO") public {
    }
}

If you're new to smart contract development, head to Developing Smart Contracts to learn about creating a new project and compiling your contracts.

To keep your system secure, you should always use the installed code as-is, and neither copy-paste it from online sources, nor modify it yourself. The library is designed so that only the contracts and functions you use are deployed, so you don't need to worry about it needlessly increasing gas costs.

Learn More

The guides in the docs site will teach about different concepts, and how to use the related contracts that OpenZeppelin Contracts provides:

  • Access Control: decide who can perform each of the actions on your system.
  • Crowdsales.
  • Gas Station Network: let your users interact with your contracts without having to pay for gas themselves.
  • Utilities: generic useful tools, including non-overflowing math, signature verification, and trustless paying systems.

The community forum.

Finally, you may want to take a look at the guides on our blog, which cover several common use cases and good practices.. The following articles provide great background reading, though please note, some of the referenced tools have changed as the tooling in the ecosystem continues to rapidly evolve.

Security

This project is maintained by OpenZeppelin, and developed following our high standards for code quality and security. OpenZeppelin is meant to provide tested and community-audited code, but please use common sense when doing anything that deals with real money! We take no responsibility for your implementation decisions and any security problems you might experience.

The core development principles and strategies that OpenZeppelin is based on include: security in depth, simple and modular code, clarity-driven naming conventions, comprehensive unit testing, pre-and-post-condition sanity checks, code consistency, and regular audits.

The latest audit was done on October 2018 on version 2.0.0.

Please report any security issues you find to security@openzeppelin.org.

Contribute

OpenZeppelin exists thanks to its contributors. There are many ways you can participate and help build high quality software. Check out the contribution guide!

License

OpenZeppelin is released under the MIT License.