Senior Blockchain Security Developer

OpenZeppelin is a company focused on blockchain security and open financial systems, founded in 2015. Their Secure Development team designs, implements, and hardens production-grade libraries and smart contracts for leading projects across multiple blockchain platforms including EVM, Starknet, Stellar/Soroban, Arbitrum Stylus, Aptos, and more. The team uses AI-native security tooling and works closely with security researchers and external auditors. The role involves joining a 24-month, multi-million-dollar project to build open-source DeFi foundations for institutional blockchain (the Canton Network). Responsibilities include delivering production-ready Reference Implementations such as privacy-preserving DEX, lending, cross-chain stablecoin settlement, confidential auction launchpad, and more. The developer will own features of the OpenZeppelin Contracts Library for Daml end-to-end, design and implement components of year-1 Reference Implementations, implement and shepherd OZ Daml versions of CIP standards, coordinate with partners, present and defend designs, work with security researchers on threat models and audits, use AI systems daily for research and development, build AI agents and workflows, contribute feedback upstream, and research privacy-preserving DeFi and Canton-specific primitives. Requirements include production fluency in Daml, deep understanding of templates, choices, multi-party authorization, and Canton architecture, 3+ years of smart contract development experience including work on Canton or similar UTXO-based or privacy-preserving architectures, production DeFi experience with primitives like AMMs, vaults, lending protocols, and cross-chain settlement, a security-first mindset with ability to build secure code and find vulnerabilities, experience with AI-native workflows and tools like Claude Code or Cursor, fluency in English for client communication, and autonomy and proactivity. Nice to have skills include cryptography or financial engineering background, institutional finance and compliance design experience, experience running an SV or contributing to Splice internals, cross-chain interoperability exposure, library/SDK API design experience, experience applying AI to security workflows, hands-on experience with non-EVM ecosystems, and open-source contributions in smart-contract or AI tooling space. The interview process is designed to be fast (~30 days) and includes recruiter, manager, team, leadership interviews, and a paid technical work trial. Benefits include fully remote work, flexible time off, paid parental leave, equipment support, medical insurance, learning opportunities, and coworking space stipend.