Senior Software Engineer, Blockchain

1inch is the DeFi ecosystem building financial freedom for everyone. 1inch products help users and builders trade, hold and track digital assets - with the self-custody, comprehensive security and the intuitive user experience they need to unlock the potential of true crypto ownership. 1inch protocols and APIs provide core infrastructure across the DeFi industry and beyond.Your missionAt 1inch, our engineering needs evolve rapidly. We are constantly seeking exceptional Web3 and smart contract developers to join our mission.We look for engineers with a high-agency, "Get Stuff Done" mindset and an unrelenting passion for decentralised innovation.As part of our engineering ecosystem, you will contribute to designing, developing, and optimising the smart contracts and underlying infrastructure powering 1inch. We value sophisticated problem-solvers who can navigate the lightning-fast shifts of the crypto landscape while executing securely at scale. Working alongside our product leads and world-class engineers, your commitment to open-source excellence will keep 1inch at the absolute cutting edge of DeFi.What You’ll DoDesign and optimise blockchain architectures with a strong focus on scalability, security, and performanceDevelop, integrate, and maintain smart contracts across decentralised protocols and infrastructure componentsConduct technical research and build proof-of-concepts for new DeFi and blockchain innovationsDesign and improve cross-chain interoperability solutions, including bridging and atomic swap mechanismsOptimise smart contract execution efficiency with a focus on gas consumption and low-latency performanceCollaborate with internal and external security auditors to identify vulnerabilities and strengthen protocol securityLead code reviews and contribute to engineering best practices, CI/CD workflows, and development standardsMentor junior and mid-level engineers while contributing to a collaborative engineering cultureWho You Are7+ years of professional software engineering experience, including 3+ years focused on blockchain developmentDeep expertise in Ethereum and EVM ecosystems, including Solidity, Yul, and decentralised application architectureStrong experience building and deploying smart contracts in production environmentsHands-on experience with Layer 2 scaling solutions and cross-chain infrastructureProven ability to drive architectural decisions and lead complex technical initiatives from design to deploymentStrong understanding of smart contract security principles, auditing processes, and vulnerability mitigationExperience working in fast-paced, high-growth engineering environmentsStrong problem-solving skills with a proactive, ownership-driven mindsetNice to havesExperience contributing to open-source blockchain or DeFi projectsFamiliarity with zero-knowledge technologies and rollup architecturesExperience building high-performance distributed systems or low-latency infrastructureUnderstanding of DeFi protocols, liquidity aggregation, or on-chain trading systemsKnowledge of Web3 developer tooling and blockchain infrastructure automation1inch is an equal opportunity employer. We are committed to evaluating all candidates on the basis of their skills, experience, and potential — regardless of race, ethnicity, nationality, gender, age, religion, disability, or any other characteristic. We believe diverse teams build better products, and we welcome applications from all backgrounds.We use AI-assisted tools to help us review applications efficiently. These tools support our recruitment team but do not make decisions on our behalf — every application is reviewed by a person before any outcome is determined. No offer or rejection is made solely on the basis of automated processing. For full details on how we use these tools and your rights in relation to them, please see our Applicant and Candidate Privacy Notice.