Senior Backend Developer (IoT / Digital Identity)

Develop back-end website applications Integrate front-end elements with server-side logic Implement core business logic Design and implement data storage solutions Apply data & security best practices - input validation, auth, secure storage, compliant logging Optimize applications for speed and scalability Design and develop APIs Participate in scalable software architecture design Maintain code integrity and organization Write clean, functional backend code Compile & analyse data to troubleshoot issues and improve performance Perform unit/integration testing, debugging, and validation Deliver solutions aligned with functional & non-functional requirements Write technical documentation Configure cloud services for backend functionality (serverless, storage, Kubernetes) Implement authentication & authorization mechanisms Maintain unit/integration tests within CI/CD pipelines Manage project scope, schedule, budget, risks & stakeholders

Remote - anywhere in the EU region | ️ Occasional travel to Belgium required | Start: Mid-September | ️ English

Are you a seasoned backend engineer with deep expertise in decentralized identity, blockchain, and secure API design? We're looking for a Senior Backend Developer to join an exciting IoT-based project, building scalable, secure server-side solutions from the ground up., 5+ years in software engineering (full-stack, backend, frontend, distributed systems) 5+ years designing scalable, secure, maintainable cloud architectures 5+ years delivering software in Agile/Scrum environments 3+ years with Decentralised Identity (DID) & W3C Verifiable Credentials 3+ years implementing OpenID4VCI and OpenID4VP 3+ years with secure credential issuance, verification & digital wallet integration 3+ years with cryptographic workflows, digital signatures & key management 3+ years developing blockchain-based/distributed-ledger solutions ️ 3+ years performing code reviews & software engineering best practices 3+ years with Digital Product Passport solutions, 10+ years backend programming (Go, C++) & server-side frameworks (Node.js) 10+ years with APM tools (Dynatrace, Splunk, Elastic APM) + OpenTelemetry 7+ years with relational (PostgreSQL, Oracle, MySQL) & NoSQL (MongoDB, CouchDB, CosmosDB) databases 7+ years with version control workflows (GitFlow, trunk-based, SVN) 7+ years designing/securing RESTful APIs (OpenAPI/Swagger) 7+ years with containerisation & orchestration (Docker, Kubernetes) 4+ years with OAuth 2.0, OpenID Connect, W3C VCDM, DIDs, SD-JWT 2+ years defining digital signature standards 5+ years with blockchain/DLT integrations, smart contracts, event-driven architecture 3+ years with Ethers.js and Web3 integrations (wallet connectivity, transaction signing) 1+ year with Zero-Knowledge Proofs (ZKP) for privacy-preserving proofs