Senior Fullstack Software Engineer (m/f/n)

A European Union Organisation based in Belgium is executing a long-term international project focused on Digital Identity, Web3, Blockchain, EBSI (European Blockchain Services Infrastructure), and Verifiable Credentials supporting the digital transformation of public services across Europe.

• University degree (minimum Bachelor's or Engineering degree) in Computer Science, Software Engineering, Electronics, Mathematics, or Physics.
• English language proficiency at minimum B2 level (CEFR) with excellent written and verbal communication.
• Ability to communicate effectively with technical and non-technical stakeholders internationally.
• Minimum 10 years of Full Stack Software Development experience using JavaScript/TypeScript.
• Minimum 3 years of hands-on experience with Web3 and blockchain-based applications.
• Minimum 2 years implementing Decentralized Identifiers (DID), Verifiable Credentials, and Digital Identity Wallets.
• Minimum 2 years designing and implementing Smart Contracts on EVM-compatible blockchain networks.
• Minimum 2 years designing, developing, and securing RESTful APIs and web services.
• Minimum 2 years working with blockchain-based tokenisation solutions.
• Minimum 2 years delivering projects within the public sector or European institutional environment.
• Minimum 8 years working in Agile/Scrum environments on complex, multi-stakeholder projects.

Technical Skills:

• Backend: JavaScript, TypeScript, Node.js, NestJS, Bun.
• Frontend: React, Next.js, React Native, HTML5, CSS3, Webpack, Vite.
• APIs & Security: REST APIs, OpenAPI, OAuth 2.0, OpenID Connect, JWT, mTLS, OWASP.
• Databases: PostgreSQL, MySQL, MongoDB, Flyway.
• Blockchain & Web3: Solidity, OpenZeppelin, Hardhat, Foundry, ethers.js, viem, ERC-20, ERC-721, ERC-1155, UUPS, Transparent Proxy, Diamond Pattern.
• Digital Identity: DID, Verifiable Credentials, EBSI, eIDAS 2.0, OpenID4VP, OpenID4VCI, SIOP v2, EUDI Wallet.
• DevOps & Cloud: Docker, Kubernetes, GitLab CI, Jenkins, ArgoCD, SonarQube, AWS, Azure.
• Submitted CVs must be in Europass format.
• EU citizenship and work location within EU required.

• Design, develop, test, and maintain full-stack software solutions.
• Build modern, responsive user interfaces using React and Next.js.
• Design and implement backend services and RESTful APIs.
• Develop and integrate Web3 and blockchain-based solutions.
• Design, implement, and maintain smart contracts on EVM-compatible networks.
• Build and integrate decentralized identity solutions, including DID and Verifiable Credentials.
• Integrate systems with European digital identity and trust-service infrastructures.
• Implement secure authentication, authorization, and cryptographic mechanisms.
• Develop automated unit, integration, end-to-end, performance, and security tests.
• Contribute to CI/CD pipelines, DevSecOps processes, and cloud-native environments.
• Translate business and technical requirements into scalable and maintainable software solutions.
• Produce and maintain technical documentation.
• Collaborate with architects, DevOps engineers, security experts, product owners, and other stakeholders.
• Ensure compliance with security best practices and software quality standards.

EU citizenship and work from within the EU is required; services must be performed from within the EU. Two physical meetings per year with the customer are foreseen at the contractor's cost. Data administration and privacy information provided by Shimi Sp. z o.o.