Anyone interviewed at OpenZeppelin or Matter Labs lately? Let's decode their proof-based security tasks.

Hey everyone,

I’ve been getting a lot of DMs lately from auditors trying to map out what top-tier protocols are actually testing for this quarter. Since we are all about proof-based Web3 recruitment here, I want to crowdsource some real-world intel on the technical bars for two of the toughest environments: OpenZeppelin and Matter Labs.

For those of you who have gone through it, what do the recent OpenZeppelin smart contract security auditor interview questions actually look like? I know their paid take-home work trials are intense.

Are they still throwing custom Ethernaut challenges at you, or are they having you manually spot complex EVM vulnerabilities—like nested reentrancy or access control bypasses—in live, unreleased codebases? I'm curious how much they let you rely on static analysis tools versus raw manual auditing.

Also, for the cryptography folks: the Matter Labs zero-knowledge engineer circuit design challenge is notorious for filtering out candidates who only know the theory. If you are doing zk-SNARKs and zk-STARKs interview preparation, how are you proving your practical skills? Are they testing you on handling arithmetic underflows in Circom or strictly on optimizing batch operations?

Drop your recent experiences below. What caught you off guard in their technical screening? I’m going to curate the best insights into an upcoming issue of the Behind Blocks newsletter so we can build a solid framework for everyone targeting these roles.