Senior Full Stack Java Developer | Diegem, Belgium

How do you evolve a large scale Java platform without losing the operational knowledge it has accumulated over more than 30 years?

That is the challenge at ILIAS Solutions.

This is not a greenfield project and it is not another consultancy assignment. You join at a unique moment. While the current platform continues to support customers worldwide, the next generation of the ILIAS architecture is already taking shape. New capabilities are developed on a modular foundation designed to support future operational readiness while preserving the strengths of today's platform.

Every day, thousands of operational decisions depend on the software we build. A single business rule can influence maintenance planning, asset availability, personnel qualifications, logistics processes, and ultimately mission readiness. Building software in this environment means understanding how those relationships interact and translating them into reliable, maintainable Java applications.

Working with Java 21 and our migration towards Java 25, Spring Boot, REST APIs, PostgreSQL, Oracle, React, Docker, Git, Maven, Jenkins, SonarQube and Mend, you remain hands on while contributing to a mature enterprise software platform used by defense organizations around the world.

If you enjoy solving complex engineering problems, staying close to the code, and building software that continues to evolve over many years, this is an opportunity to make a lasting technical impact.

Software That Explains Operational Readiness

Software at ILIAS supports the complete operational lifecycle of defense assets.

An aircraft may become unavailable because maintenance is overdue. A vehicle may remain unavailable because a spare part has not yet arrived. A mission may be delayed because required personnel qualifications have expired.

Your software helps explain those relationships.

Rather than building isolated functionality, you translate highly connected business rules into software that allows users to understand why assets are or are not operationally ready. The result is software that supports informed decisions across maintenance, logistics, planning, and operational readiness.

Customers rarely arrive with technical specifications.

They arrive with operational challenges.

Success in this role comes from understanding how operational processes, business rules, and system interactions fit together before translating them into software.

You analyse requirements, identify dependencies, and take ownership of user stories from analysis through implementation. Working closely with analysts, architects, and product owners, you deliver software that remains reliable, maintainable, and scalable while the platform continues to evolve.

Although the platform is evolving towards a new modular architecture, this remains first and foremost a hands on Senior Java Developer role. You enjoy building software yourself and continue writing production code every day.

• Build one enterprise platform instead of moving between customer projects.
• Work with Java 21 today while helping shape the migration towards Java 25.
• Help modernise a platform that has evolved over more than thirty years.
• Solve engineering challenges driven by complex operational business rules.
• Stay hands on while working alongside experienced software engineers, analysts, and architects.
• Contribute to software that supports operational readiness across defense organizations worldwide.

• Collaborate within a Scrum team applying Domain Driven Design principles
• Analyse operational requirements and translate them into software functionality
• Take ownership of user stories from analysis through implementation and delivery
• Design, develop, and maintain enterprise applications using Java and Spring Boot
• Build and enhance REST APIs and backend services
• Contribute to frontend development where required
• Remain hands on in the design, development, testing, and maintenance of software components
• Write clean, maintainable, and well tested code
• Participate in code reviews and technical discussions
• Troubleshoot technical and functional challenges across the full stack
• Translate customer feedback into product improvements
• Ensure applications remain secure, scalable, reliable, and maintainable
• Contribute to knowledge sharing and continuous improvement within the team

• You have built enterprise software using Java, Spring Boot, REST APIs and relational databases and enjoy remaining hands on throughout the software development lifecycle.

• You have developed a strong foundation in software engineering through higher education in Computer Science, Software Engineering, Information Technology, or through equivalent professional experience.

• Over the years, you have gained experience developing enterprise applications using Java, Spring Boot, REST APIs, relational databases, and modern development practices.
  
  

• You enjoy staying close to the code and take pride in building software yourself. You bring recent hands on experience developing enterprise applications in Java and are comfortable working with modern Java versions, evolving frameworks, and contemporary development practices.

• You can take a challenge that is difficult to explain, break it down into understandable concepts, and translate it into reliable software solutions.

• You recognise patterns, identify dependencies, and understand how technology, processes, and business rules come together to support operational outcomes.\

• You communicate clearly and work effectively with both technical and functional stakeholders.

• You are fluent in Dutch or French and have a professional command of English