OpenZeppelin Contracts 3.4 includes an ERC777 security fix for potential reentrancy issues in custom ERC777 extension, virtual view functions, ERC20 permit in drafts, Beacon proxy, and a Minimal Proxy (Clones) library.

How to protect your contracts against reentrancy after Ethereum’s Istanbul hard fork.

A stable, audited, and fully tested package for smart contract development

ZeppelinOS is all about making the technology of upgradeability into an accessible and frictionless tool for developers. Ideally, we want to enable a developer to create upgradeable instances...

When developing a crowdsale smart contract, there are several options for handling the collection of funds. In this post, we’ll analyze the most common approaches, and try to assess their degree of security and transparency.