Backend Software Engineer

Language: English

Can work anywhere from the EU region, Occasional travel to Belgium will be required

Requirements

• Education: Bachelor's degree in IT, Engineering, Mathematics, Business Administration or Innovation.
• Software development experience: at least 15 years.
• Software engineering principles, modern web development practices and SDLC: at least 15 years.
• Back-end software development using Java, JavaScript, TypeScript and Node.js: at least 10 years.
• Design, development, testing and deployment of blockchain smart contracts on EVM-compatible networks: at least 10 years.
• Blockchain security, including smart contract testing, vulnerability assessment, secure development practices and audit preparation: at least 10 years.
• Ethereum smart contract development: at least 5 years.
• Solidity, EVM, upgradeable contracts, Contract Factory, Beacon Proxy, UUPS, Transparent Proxy, EIP-2535 Diamond Standard, gas optimisation, storage layout and RBAC: at least 5 years.
• Hyperledger Besu network engineering, including deployment, configuration, operation and maintenance of permissioned blockchain networks: at least 5 years.
• Hyperledger Besu, QBFT, IBFT2, live network upgrades, Genesis configuration, hard forks, troubleshooting and forensic diagnosis: at least 5 years.
• Experience as a validator coordinator or blockchain infrastructure engineer responsible for Hyperledger Besu validator networks: at least 5 years.
• Blockchain-based digital identity and tokenisation solutions: at least 5 years.
• Blockchain standards, digital identity and tokenisation technologies, including ERC-20, ERC-721, ERC-1155, ERC-1167, EIP-712, EIP-1559, DIDs, Verifiable Credentials and tokenisation: at least 7 years.
• Blockchain security, development and DevSecOps tooling: at least 5 years.
• Experience with Foundry, Hardhat, OpenZeppelin, Slither, Mythril, fuzz testing, SWC Registry, OWASP Smart Contract Top 10 and smart contract audit preparation: at least 5 years.
• Experience with ethers.js, VIEM, Gnosis Safe, hardware wallets, EIP-712 signing, ECDSA and key management: at least 5 years.
• GitLab CI/CD experience: at least 5 years.
• Experience with Puppet: at least 5 years.
• Ability to design and develop APIs and integrate smart contracts with backend services, wallets and dApps.
• Experience with secure backend development, including authentication, authorisation, input validation, secure storage, compliant logging and monitoring.
• Experience with unit and integration testing and integrating tests into CI/CD pipelines.
• Ability to write clean, functional backend code and technical documentation.
• Experience in troubleshooting, debugging and optimising applications for performance and scalability.
• Experience in managing teams of developers.
• English: minimum B2 level, with strong written and oral communication skills.
• Certified Scrum Master or equivalent Scrum Master certification.
• Certified Product Owner or equivalent Product Owner certification.

Nice to have

• Experience with AI-assisted software development tools, e.g. Claude Code.
• Previous experience in EU institutions or European Commission projects.