Senior Security Engineer - Remote

Mysten Labs believes that decentralized and open protocols are the bedrock of the internet of value. This is why at Mysten Labs, we are creating foundational infrastructure to accelerate the adoption of decentralized protocols based on blockchain technologies.

We’re looking for a Senior Security Engineer to help protect the Sui ecosystem. You’ll uncover vulnerabilities, build monitoring tools, and assess economic risk across DeFi protocols. Working closely with external protocol teams and Mysten’s own DeFi products, including DeepBook, you’ll help address risks before they become incidents and strengthen security across the ecosystem

Build and run continuous monitoring of the Sui DeFi ecosystem for security and economic risk: oracle issues, misconfigurations/bad economic parameters, solvency and bad-debt exposure under price shocks, liquidation capacity against on-chain liquidity depth, accounting-versus-positions reconciliation, invariants.

Extend security team tooling, both precise static analysis tooling and proprietary agent skills.

Measure and drive compliance with the DeFi security recommendations across supported protocols: run the recurring compliance cycle, fill the protocol report card, validate security claims (audits, custody, upgrade governance, oracle dependencies) against on-chain reality, track remediation commitments, and elevate when a protocol regresses or fails to disclose an incident. Be the security team's point of contact for external DeFi teams and for Mysten's own DeFi products such as DeepBook: due diligence, incident coordination, and post-mortems that feed back into the recommendations and the monitors.

Write it down: findings, reports, and runbooks that a protocol engineer can act on and a non-technical stakeholder can understand, with every claim traceable to bytecode, chain state, or data.

Bachelor's degree in Computer Science, Computer Engineering, a relevant technical field, or equivalent practical experience.

• 3+ years of hands-on experience in security engineering, smart contract security, or DeFi risk engineering, with a track record of building tools that ran in production and of finding real vulnerabilities (audit findings, bug bounty reports, published research, or incident work).
• Strong understanding of DeFi mechanics and their failure modes: lending markets (LTV, liquidation thresholds and bonuses, close factors, bad debt), AMMs and concentrated liquidity, perpetuals, liquid staking, oracles (staleness, confidence, TWAP, multi-source aggregation), flash loans, and MEV.
• Proficiency in TypeScript and Python, and comfort with Rust. Ability to write SQL over large datasets and to work with blockchain indexers and data warehouses.
• Experience reading smart contract code at source or the bytecode or disassembly level, or evident ability to learn it quickly. Solidity or Rust smart contract experience transfers.
• Rigor: you verify claims against bytecode and chain state, build known-clean checks into your tools, and say what you did not verify.
• Knowledge of the recent DeFi exploit history on Sui and other chains: named incidents, oracle compromises, and the defect classes behind them.

Experience building analysis or monitoring tools with LLM agents (Claude Code skills or comparable), and a clear sense of where models help and where deterministic tooling must do the work.

Static or dynamic program analysis experience: taint analysis, call graphs, symbolic execution, fuzzing, formal verification.

Quantitative or economic modeling experience: stress testing, liquidity modeling, risk parameters for lending markets.

Our team is remote first and we are hiring across the world. We raised a $300M Series B round from top Silicon Valley led venture funds like Jump Crypto, Andreessen Horowitz (a16z), Binance Labs, Redpoint, Lightspeed, Coinbase Ventures, Electric Capital, Standard Crypto, NFX, Slow Ventures, Scribble Ventures, Samsung Next, Lux Capital, among other investment firms and strategic partners.