Reentrancy After Istanbul

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

Announcing OpenZeppelin 2.0

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

Towards frictionless upgradeability

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...

Handling Crowdsale Funds Securely

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.