Java Developer - GraphDB & Semantic Web | European Institutions

WHO WE ARE Edda International, a dynamic and rapidly growing European group of companies with an estimated 2024 turnover of 20+ MEUR, 220+ employees and 15+ years of experience. Operating out of Luxembourg and Brussels, Edda International manages large International Institutions Framework Contracts delivering Information Technology services throughout geographical Europe. WHAT WE ARE LOOKING FOR Java Developer - GraphDB & Semantic Web | European Institutions We are currently looking for two highly motivated Java Developers to support our client's projects at a prestigious European Institution in Luxembourg (Kirchberg). The mission involves working with graph databases and semantic web technologies, driving innovation in data representation, retrieval, and UI integration. We are hiring for: 1 Junior Developer (1-4 years of experience) - full-time onsite 1 Senior Developer - flexible model: onsite, near-site (within 2h travel) or remote (minimum 20% onsite) In these roles, you will contribute to software development activities in the domain of semantic web, data visualization, and search technologies used by one of the most influential institutions in Europe. YOUR TASKS Design and develop scalable Java applications integrated with GraphDB technologies Write and optimize SPARQL queries Develop and maintain ETL processes for existing and new tools Implement new features and extend internal applications built with Java and graph databases Create and integrate UI filters, data presentation layers, and backend services Manage different development environments and CI/CD pipelines Contribute to architectural decisions and evaluate technology options Optionally, support front-end styling and interaction Collaborate with institutional stakeholders on product improvements Support Proof-of-Concept (PoC) creation and adaptive development YOUR SKILLS AND EXPERIENCE Strong experience in Java development Hands-on experience with SPARQL, RDF, and GraphDB technologies (e.g., Ontotext, Blazegraph, etc.) Familiarity with semantic web concepts such as OWL and SHACL is a strong asset Proficiency with Elastic Search is a plus Capable of working independently and proactively Understanding of front-end/backend data flow CI/CD and versioning experience (e.g., Git, Jenkins) Previous experience in EU institutions is a plus Bonus: project management experience or familiarity with institutional workflows EXTRA INFORMATION Contract type: Permanent employment or freelance Start date: September/October 2025 Location: Luxembourg (Kirchberg) Work mode: Junior: On-site, 5 days/week Senior: On-site or near-site (within 2 hours from Kirchberg) or remote with minimum 20% onsite Relocation required if beyond 2h travel from Kirchberg for full on-site positions At Edda International, we are committed to supporting a Diverse and Inclusive Community. This position is open to EU citizens or non-EU citizens already residing in the EU with a valid work permit, due