Senior Software Engineer, Formal Verification

Category Labs (formerly known as Monad Labs) is a team of systems engineers and researchers on a mission to design and build at the frontier of decentralized technology. We strive to deliver significant improvements over existing blockchain solutions. After raising $225M in series A funding, led by Paradigm, we are growing our team. We’re the team behind Monad, a high-performance, EVM-compatible Layer 1 whose public mainnet is now live. We write the core software that runs it: a parallel-execution EVM https://github.com/category-labs/monad, a custom state database, and a BFT consensus client https://github.com/category-labs/monad-bft, all developed in the open. THE ROLE We’re hiring a Senior Software Engineer in Formal Verification to prove the correctness of the Monad implementation. Your work will involve writing machine-checked proofs about real production C++ code, including concurrent features like optimistic execution and novel Monad mechanisms such as reserve balance and optimized page-level storage. You’ll work in Rocq (formerly Coq), using the Iris separation logic framework and the BRiCk formal semantics of C++, building models of our designs and proving the implementation equivalent to them, as a vital member of a small, high-performing team. WHAT YOU’LL DO - Formally verify the highest-risk parts of the Monad implementation, including concurrent and parallel execution logic. - Build and refine Rocq models of system designs, then prove the C++ implementation equivalent to those models, catching design and implementation bugs before they reach main. - Develop specifications and weakest-precondition proofs for production C++ using BRiCk and Iris separation logic. - Strengthen theorem statements and proof automation, and devise approaches that scale verification to a fast-moving codebase. WHO YOU ARE - You have at least 5 years of software engineering experience in C++, much of it building performant systems from scratch – databases, device drivers, embedded systems, or the like. - You have hands-on experience with an interactive theorem prover, ideally Rocq (formerly Coq), and can write machine-checked proofs about real, running code. - You reason about concurrency and memory with a rigor most engineers never need – and you're drawn to problems where "probably correct" isn't good enough. - You have sharp instincts for software architecture, memory management, and performance profiling. - You hold a Bachelor's, Master's, or PhD in Computer Science, or have equivalent experience. - You communicate clearly and thrive on a small team where everyone owns the result. WHY WORK WITH US - Challenging problems: You’ll work on extremely challenging problems with massive impact. See our Blogs https://www.category.xyz/blogs and Publications & Talks https://www.category.xyz/papers-talks for a flavor of the problems we are solving in the real world. - Huge opportunity: The Ethereum Virtual Machine (EVM) standard is ubiquitous, but existing EVM-compatible chains are very slow. Monad’s core innovations offer developers the best of both worlds (portability and performance) and are a game-changer for mass user adoption in crypto. - The right team: You’ll be part of a small, exceptional team (engineers and researchers make up 90% of the team). - Open by default: Our core software is public on GitHub. You’ll build in the open, and your work ships where the whole ecosystem can see it. - Culture: We’re a lean team working together to achieve very ambitious goals. We are united in our culture of collaboration, low ego, and high-quality output. As an early member of our team, you’ll help to shape our culture. - Compensation: You’ll receive a competitive salary and equity package. - Resources and growth: We’re well-capitalized, with backing https://x.com/monad_xyz/status/1777687376136982767 from leading venture funds like Paradigm, Electric Capital, Greenoaks, Dragonfly, and Coinbase Ventures. We keep a lean team, and this is a rare opportuni…