Backend Developer (Java 21, Spring, Networking and Messaging) for NATO with security clearance

This is straightforward, satisfying development work on a suite of tools that real operators use. You would design, build, test and maintain it, and keep the documentation honest — under a lead developer, alongside a service delivery manager and a project manager, in a team small enough that requirements discussions actually include you.

The stack is current rather than legacy: Java 21 with Spring on the back end, Angular 20 on the front, and the usual tooling around it. There is real networking underneath, so the work rewards someone who understands what happens below the framework.

What you would be doing

• Design, develop, test and maintain the software for the tool suite.
• Write and keep current the software documentation.
• Take part in requirements elicitation, analysis and design discussions.
• Keep the development backlog updated with real progress and comments.
• Fix bugs and improve stability rather than only adding features.
• Create and run test cases, and support users through acceptance testing.
• Take part in team meetings as the lead developer and the delivery managers require.

What you would bring

• At least three years of Java back-end development on recent versions — Java 21 and Spring.
• And/or three years of front-end development in Angular, on a recent version.
• Hands‑on development tooling: Git, Maven, Jira, Jenkins.
• Networking experience — TCP/IP and UDP — and work with messaging systems.
• Testing experience across the full software lifecycle.
• A proven ability to work in a multinational team, in fluent business English.

Experience with military data links is preferred but not required. The work is full time on site in The Hague.