Senior Java Software Engineer

Senior Java Developer - Microservices Architecture (Freelance/Contract)

This is a long-term opportunity for a hands-on Java expert who enjoys working on technically demanding projects involving architectural redesign, microservices, and modern development practices. The ideal person is proactive, self-driven, and capable of balancing deep technical focus with a user-centric and business-aware approach.

Location: Brussels (Hybrid - up to 1 week per month on site)

Start Date: ASAP

End Date: 15 November 2030

Overview

We're looking for a Senior Java Developer with a strong background in microservices architecture to join an Agile engineering team working on several modernisation and innovation projects. You'll play a key role in redesigning a large-scale desktop application into a microservices-based architecture and developing internal tools such as monitoring dashboards to improve developer efficiency.

As the project evolves, you'll also have the opportunity to contribute to the development of new microservice-based applications and other key systems within the team. This role requires a combination of deep technical expertise, architectural understanding, and strong collaboration skills to work effectively with business stakeholders and fellow developers.

Key Responsibilities

Lead the redevelopment of a legacy Java desktop application into a microservices architecture.

Contribute to architectural design discussions and make key technology decisions.

Build internal tools (e.g., monitoring dashboards, developer utilities) to support the wider engineering team.

Collaborate within an Agile/Scrum team, ensuring alignment with project goals and timelines.

Apply best practices in cybersecurity, code quality, and documentation.

Maintain a user-centric mindset and work closely with business teams to translate requirements into practical solutions.

Drive innovation, share knowledge, and mentor other developers when needed.

Technical Skills Required

Languages:

Proficiency in French and/or Dutch (C1 level or higher).

Proficiency in English (C1 level or higher).

Technical Expertise:

Java (10+ years) - expert-level development skills.

Java 17-21 - hands-on experience with modern Java features.

SpringBoot / SpringData (2+ years) - strong experience with RESTful microservices.

Microservices & Web Services (2+ years) - REST API, JSON, service integration.

JPA / Hibernate (2+ years) - solid experience in ORM and persistence.

Relational Databases (5+ years) - MySQL, MariaDB, or similar.

Unit Testing (2+ years) - JUnit, Mockito, PowerMock, or equivalent.

Build & CI/CD Tools (5+ years) - Maven, Git, GitLab, SonarQube.

Containerisation & Cloud - experience with OpenShift, Docker, Podman, or Kubernetes.

Design Patterns - strong understanding of clean architecture principles and reusable design patterns.

Agile/Scrum (2+ years) - experience working in collaborative, iterative environments.

If you're an experienced Java Developer feel free to apply or send your C.V to [email protected]

Senior Java Developer - Microservices Architecture (Freelance/Contract)