OpenZeppelin / openzeppelin-contracts

Reusable, community-audited Solidity smart contract library with ERC20/ERC721 implementations and role-based access control.

foundry-rs / forge-std

Solidity test helper library providing cheatcode wrappers, error constants, storage utilities, and assertions for Foundry tests.

Vectorized / solady

Gas-optimized Solidity snippets and contract libraries for Ethereum, including ERC20, ERC721, and ERC1155 implementations.

across-protocol / contracts

Solidity smart contracts for Across, a cross-chain token bridge with a HubPool on Ethereum and SpokePools on other networks.

a16z / erc4626-tests

Foundry property-based test suites that check whether an ERC4626 vault implementation meets the standard's requirements.