Senior Software Engineer, Blockchain (Smart Contracts)

Your mission

At 1inch, our engineering needs evolve rapidly. We are constantly seeking exceptional smart contract engineers to join our mission. We look for engineers with a high-agency, 'Get Stuff Done' mindset and an unrelenting passion for decentralised innovation. We also embrace AI as a force multiplier for engineering, and value developers who thoughtfully leverage AI-powered tools to accelerate development, improve code quality, and solve complex technical challenges. 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 do

• Design and optimise blockchain architectures with a strong focus on scalability, security, and performance
• Develop, integrate, and maintain smart contracts across decentralised protocols and infrastructure components
• Conduct technical research and build proof-of-concepts for new DeFi and blockchain innovations
• Design and improve cross-chain interoperability solutions, including bridging and atomic swap mechanisms
• Optimise smart contract execution efficiency with a focus on gas consumption and low-latency performance
• Collaborate with internal and external security auditors to identify vulnerabilities and strengthen protocol security
• Lead code reviews and contribute to engineering best practices, CI/CD workflows, and development standards
• Mentor junior and mid-level engineers while contributing to a collaborative engineering culture

Who you are

• 7+ years of professional software engineering experience, including 3+ years focused on blockchain development
• Deep expertise in Ethereum and EVM ecosystems, including Solidity, Yul, and decentralised application architecture
• Strong experience building and deploying smart contracts in production environments
• Hands-on experience with Layer 2 scaling solutions and cross-chain infrastructure
• Proven ability to drive architectural decisions and lead complex technical initiatives from design to deployment
• Strong understanding of smart contract security principles, auditing processes, and vulnerability mitigation
• Experience working in fast-paced, high-growth engineering environments
• Strong problem-solving skills with a proactive, ownership-driven mindset

Nice to haves

• Experience contributing to open-source blockchain or DeFi projects
• Familiarity with zero-knowledge technologies and rollup architectures
• Experience building high-performance distributed systems or low-latency infrastructure
• Understanding of DeFi protocols, liquidity aggregation, or on-chain trading systems
• Knowledge of Web3 developer tooling and blockchain infrastructure automation