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Salary: PLN 300,000 - 380,000 / annual
Fireblocks is a leading digital asset infrastructure platform trusted by major financial institutions, banks, and Web3 companies worldwide. The FinApps Access team builds the backbone of on-chain access for enterprise clients and crypto-native organizations, operating at the intersection of blockchain protocol engineering and enterprise-grade reliability.
In this role, you will design and build robust, scalable backend services supporting high-volume on-chain transaction flows across multiple blockchain networks (both EVM and non-EVM). You'll own end-to-end development of backend components and APIs, from architecture decisions through production deployment. Key responsibilities include leading integrations with DeFi protocols and on-chain data sources, researching emerging blockchain technologies to keep Fireblocks at the cutting edge, and optimizing production systems for performance, reliability, and security.
You'll drive features from inception through delivery at scale, taking full ownership of the product lifecycle. Collaboration with product, protocol research, and platform engineering teams is essential to deliver high-quality solutions on time.
Required qualifications: 7+ years as a Backend or Full Stack Engineer with a B.Sc. or equivalent. You must have deep blockchain and Web3 experience, including understanding of transaction lifecycles, consensus mechanisms, smart contract interactions, and on-chain data. Proven experience across multiple blockchain ecosystems (EVM chains like Ethereum, Polygon, Arbitrum, and non-EVM chains like Solana, TON, Tron) is essential. Proficiency in Node.js and TypeScript, experience designing microservices in production CI/CD environments, and strong security/cryptography knowledge are required. Familiarity with DeFi protocols and Web3 tooling (ethers.js, viem, web3.js) is a strong advantage. Full-stack experience with React is a nice-to-have.
You think in systems, care deeply about correctness and reliability at scale, and are comfortable navigating ambiguity. You have natural curiosity about blockchain protocols and actually read the specs. You thrive in fast-moving environments, balancing shipping velocity with code quality, and communicate clearly across engineering, product, and research teams.
