Expert Test Engineer

Freelance Expert Test Engineer | Brussels | Hybrid

For a major organisation in the public sector, we are looking for an experienced Expert Test Engineer to join a large-scale digital modernisation programme.

Duration: 12 months, with possible extension

Level: Expert – 10+ years of professional experience

The role

You will join an experienced and highly skilled Agile delivery team working on a major digital transformation programme involving cloud, APIs, microservices, Zero Trust and event-driven architecture.

As an Expert Test Engineer, you will be responsible for defining, designing and implementing the overall test strategy and ensuring the quality of the solution through a high level of test automation.

This is a hands-on engineering role. We are specifically looking for someone who has personally implemented and worked with the required technologies and testing practices, not someone whose experience is limited to managing or coordinating teams.

• 10+ years of professional experience as a Test Engineer
• 5+ years hands-on experience with test automation
• 5+ years hands-on experience with API testing, preferably Bruno
• 5+ years hands-on experience with UI testing, preferably Cypress
• Good knowledge of HTML DOM
• 5+ years experience with regression and integration testing, preferably JUnit & Cucumber
• 5+ years experience with performance, stress and load testing, preferably JMeter & Gatling
• 5+ years experience with E2E testing
• 5+ years experience with CI/CD pipelines and test integration, preferably Azure DevOps
• 5+ years experience with contract testing, mocking and service virtualisation
• 5+ years experience with monitoring & observability, preferably Grafana
• 3+ years hands-on Java SE 10+ development experience
• 3+ years experience with SQL databases
• 5+ years experience working in Agile delivery teams
• Experience with cloud-native environments
• Experience with APIs and microservices
• Ability to independently design and implement test strategies and automation
• Experience designing and developing APIs
• Experience developing and integrating microservices
• Experience with cloud, API and event-driven software architecture
• Experience with event-driven architectures
• Knowledge of BDD / Event-Driven Development
• Knowledge of Domain-Driven Design (DDD)
• Experience within a federal/public-sector environment

English: good professional level

AND either Dutch OR French: good professional level

You must be comfortable working in a bilingual environment and communicating with both technical and non-technical stakeholders.

A higher-education degree in Computer Science / IT from a recognised university or university college within the European Union is mandatory.

We are looking for a pragmatic, hands‑on Test Engineer who:

• Takes ownership from analysis through design and implementation
• Is passionate about software quality and test automation
• Can challenge existing approaches and propose alternative solutions
• Communicates effectively with technical and business stakeholders
• Works well within multidisciplinary Agile teams
• Is comfortable working on‑site 3 days per week in Brussels

Please note: This is not a pure management, coordination or consulting assignment. The role requires significant hands‑on technical implementation.