Senior Software Engineer, Formal Verification

About the role

You will own the correctness of the most critical execution paths inside Monad by constructing machine-checked proofs that guard against subtle concurrency bugs. Your days will be spent reasoning about optimistic execution and novel mechanisms such as reserve balance at the highest level of rigor. You will act as the final gatekeeper before new C++ logic reaches mainnet, ensuring that implementation bugs are caught in the proof stage. This role gives you direct ownership over the foundational verification infrastructure that keeps the chain safe. You will collaborate tightly with systems engineers and researchers who value precision over speed. Your proofs will be reviewed and built upon by a small, high-performing team that expects clarity and robustness. Over time, your work will define the bar for formal methods across the broader Monad ecosystem.

Key facts

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.
• Integrate verification workflows into the development rhythm of a rapidly evolving production system.
• Partner with systems engineers to translate informal designs into precise formal specifications.
• Mentor engineers on effective proof strategies and patterns that remain maintainable in a high-velocity environment.
• Ensure that verified components interoperate safely with the broader stack, including the parallel-execution EVM and custom state database.

Requirements

• 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 are 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.
• You are comfortable working with low-level systems concepts and high-level formal reasoning in the same day.
• You care deeply about delivering verified code that can withstand real-world adversarial conditions.

Practical notes

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 opportunity to join. You'll learn a lot and grow as our company scales.

How we use AI

We're an AI-native team, and we expect engineers to use coding agents and keep up as the tooling evolves. A few things we believe:

• AI is leverage, not a crutch. Review what it generates with the same scrutiny you'd give a teammate's PR, and own every line you ship.
• Judgment is what matters, not how long you typed by hand. We won't ask for "N years of [tool]." The stack turns over every few months, so what matters is that you pick up new tools fast and know where and when they apply.

Salary and benefits

The base salary range for this role is $180,000 - $250,000. This reflects the minimum and maximum range across US locations. It does not include benefits, token, or equity incentives. The final offer may vary based on factors such as relevant skills, experience, domain expertise, and work location. If you are based outside of the US, we have geographic variations that may affect the final number, and these details can be discussed during the hiring process.