Starting a large codebase from its smallest files, and the OpenZeppelin multicall bug

We started the Panoptic contest on Code4rena.

Lesson Summary:

• OpenZeppelin's multicall had a bug when combined with meta-transactions.
• If the protocol is large, start with the small files — constants, libraries, types — so you build context before the harder parts.
• Converting uint to int can go wrong.

Watch the session on YouTube ↗