Upgradeable contracts allow us to alter a smart contract to fix a bug, add additional features, or simply to change the rules enforced by it. Smart contract upgrades can be managed using OpenZeppelin Defender.

Access control—that is, “who is allowed to do this thing”—is incredibly important in the world of smart contracts. The access control of your contract may govern who can mint tokens, vote on proposals, freeze transfers, and many other things. It is therefore critical to understand how you implement it, lest someone else steals your whole system.

The DeFi space, and recently the NFT space, have continued to see a variety of exploits and even insider attacks resulting in vault losses, unexpected liquidations, and fraudulent token mints. OpenZeppelin Defender can help teams detect these types of attacks and abnormal behavior and automatically respond to quickly mitigate the attack.

Clones (minimal proxies) as described in ERC1167, are very small, and cheap to deploy, smart-contracts that delegate all incoming calls to an implementation (template) contract containing the functionality.

Gasless MetaTransactions with OpenZeppelin Defender. The workshop covers the following: Intro to MetaTransactions; How to accept meta-txs in a contract using OpenZeppelin Contracts; Relay meta-txs using Defender Autotasks and Relayers; Send meta-txs from your dApp;
You can watch the video, view the slides, try the demo app and setup your own relayer and app using the code from the workshop.

That’s a wrap! ETHDenver 2019 has just finished up, and while everyone is exhausted, we couldn’t be more thrilled at how vibrant and active the community is!

¡Hola Zeppeliners! It’s that time again, when hackers, innovators, and Bufficorns converge on ETHDenver for a week of #buidl, #buidl, #buidl!

After the fun we had with last year’s Ethernaut hacking game, we’re releasing EthHunt, a new game to celebrate Zeppelin’s sponsorship of Devcon4!

As we’re wrapping up EthDenver 2018, the #gratitude hashtag falls short to say thanks to all the awesome people who contributed to make it an unforgettable event.