Security Engineer

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

Responsibilities

• 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 escalate when a protocol regresses or fails to disclose an incident. Partner with the ecosystem and finance owners of the process.

• Hunt for critical vulnerabilities in the highest-TVL Sui protocols and get them fixed before they are exploited: full-package audits, variant analysis across forks, pre-execution review of multisig upgrade payloads, and forensics after incidents anywhere in the ecosystem.

• 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.

Minimum Qualifications

• 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).