Security Engineer
Liam Horne is an English-born, Canadian-raised software entrepreneur and engineer who has spent his career building Ethereum scaling technology, from state channels to Optimism and Base, and is now building Tempo, a payments-focused L1 blockchain.
About Liam Horne
Liam Horne studied Computer Science at the University of Waterloo before dropping out to start a startup. He spent most of his twenties working on Ethereum technology, beginning with scaling payments via state channels (building projects like Web3Torrent), then pivoting to build Optimism, one of the defining projects of the Layer 2 rollup ecosystem, and co-launching Base with Coinbase on the OP Stack. Around 2023 he shifted focus to stablecoins, writing and working on projects such as World Chain, Stable, and Build Canada: Crypto after observing that Tether on Tron dominated real-world stablecoin usage despite Ethereum scaling efforts. This work led him to Tempo, a payments-first infrastructure L1 blockchain project he is currently building and hiring for. He is also an active startup investor, having invested in companies including Othership, QA Wolf, Daimo, Erebor, Stable, Farcaster, Ambrook, Mercantile, Software Applications Incorporated, Conduit, Splits, Axiom, OpenSea, Agora, and Flex.
Skills
About the Role
You will join a full-time internal Red Team dedicated to continuously stress-testing Tempo's infrastructure. Rather than checking compliance boxes, you'll write Rust fuzzers, simulate economic attacks on the testnet, and dissect the EVM to uncover edge cases in the execution client. You'll treat mainnet like a continuous CTF challenge, build custom security tooling and automation, partner with engineering teams to review critical architecture, and analyze incentive structures and game-theoretic risks to prevent economic exploits.
Requirements
- Fluency in reading and writing production-level code in systems languages, with a strong preference for Rust
- Deep expertise in EVM internals, including knowledge of opcodes, storage slots, gas metering, and precompiles
- Proven track record of offensive security, such as high rankings in CTFs (e.g., Paradigm CTF), high-severity bug bounty submissions, or published research
- Experience building custom security automation or tooling rather than relying solely on off-the-shelf scanners
- Bleeding-edge knowledge of the latest blockchain security research, including recent hacks and how these could have been mitigated
Responsibilities
- Proactively hunt for vulnerabilities in the Tempo protocol, consensus engine, and bridge architecture
- Design and implement security tooling and automation in liaison with the Foundry team to catch logic errors and edge cases
- Partner with engineering teams to review critical architecture across the codebase
- Analyze incentives and game-theoretic risks within the protocol, such as MEV and staking dynamics, to prevent economic exploits