About Project ElevenProject Eleven is an applied lab of builders and technologists working at the intersection of quantum computing and cryptography. We build impactful solutions that push the digital-asset ecosystem to a more secure future, with a focus on post-quantum migration: upgrading wallets, identity, and settlement rails to quantum-safe primitives without breaking UX, composability, and developer workflows.Our mission is to future-proof digital assets and preserve self-sovereignty in a post-quantum world by building canonical tooling and products teams can adopt: crypto-agile infrastructure, reference implementations, and integrations that fit real constraints like latency, cost, compatibility, key rotation, and recovery.We work with leading ecosystems through products we build, audits, testnets, and cutting edge research, aiming for a proven upgrade path and production-ready tooling where users retain control of their assets and identity.The roleWe're looking for a Senior Protocol Engineer to join our growing Product Engineering team. As a Protocol Engineer, you'll help build canonical tools and products to protect digital assets and preserve self-sovereignty in a post-quantum world.This role is a full-time, fully remote position in Europe (GMT to GMT+2).What you'll be responsible forDesign, implement, and maintain long-lived smart contracts intended for production use and high-value deploymentsOwn contract architecture decisions including upgradeability, storage layout, initialization, and lifecycle managementIdentify, mitigate, and document security risks related to smart contracts and on-chain protocol logicPrepare contracts for external audits, respond to findings, and implement remediation safelyDevelop comprehensive test suites including unit tests, integration tests, fork testing, and fuzzingManage contract deployments, upgrades, and post-deployment monitoring in live environmentsCollaborate with off-chain engineers to ensure safe and consistent interaction between on-chain and off-chain systemsEvaluate and adopt relevant standards and best practices within the smart contract ecosystemWhat you bringDeep experience with Solidity development and shipping production contractsStrong understanding of proxy patterns, upgrade safety, storage, initializer patterns, and contract lifecycle managementExcellent knowledge of EVM internals and common vulnerabilities (e.g., Reentrancy, storage collisions, signature replays)Demonstrable experience preparing contracts for formal auditsFamiliarity with ERC standards (especially ERC-20, ERC-721, ERC-4337, ERC-1271)Experience deploying and maintaining high-value contracts on mainnet (e.g., deployments, proxy upgrades with no downtime, post-deployment monitoring)Strong testing and debugging (e.g., complex integration tests, gas profiling and optimisations, fork testing, fuzzing)Strong English communicationWhat we'd love to seeExperience with ERC-4337 account abstractionAwareness and understanding of post-quantum cryptographyExperience developing with ZeroDev, Biconomy or Alchemy accountsToken Sale/ICO experience (vesting schedules, token distribution contracts, TGE mechanics)Auditor collaboration (working with auditors and running internal pre-audits)Experience contributing to Ethereum standards, open-source crypto projects, AA frameworks or walletsEqual OpportunityWe are committed to equal employment opportunity and believe that diverse teams build better products. All qualified applicants will receive consideration without regard to any protected characteristic under applicable law.
