Medior Test Specialist-ATR000300

Location: Brussels Belgium
Start Date: 9 November 2026
End Date: 9 November 2028
Work Regime: 100%
On-site: Minimum 2 days per week with additional on-site presence when required
Duration: 440 working days per person

We are looking for 4 Medior Test Specialists to join a testing team responsible for planning and executing System Acceptance Testing (SAT) sanity testing regression testing and functional testing.

The team also supports defect analysis during major releases and may execute testing for market and distribution-related processes. Testing is performed using both Waterfall and Agile/Scrum methodologies.

• Execute sanity regression functional and SAT testing.
• Write and maintain test scenarios and test cases.
• Perform first-line analysis and follow-up of defects.
• Log prioritize track and follow up defects according to priority.
• Execute functional and integration tests across different business and application domains.
• Execute ad-hoc testing requests from functional/business analysts.
• Work with SOAP UI and XML-based interfaces.
• Write and execute SQL queries.
• Read and understand Technical Design Documents including if/then/else logic.
• Collaborate closely with analysts test coordinators domain leads and technical teams.
• Participate in Agile/Scrum and Waterfall testing activities.
• Contribute ideas to improve test execution test coverage and testing approaches.
• Participate in knowledge-sharing and onboarding activities.
• Attend daily stand-ups and alignment meetings and contribute to meeting preparation and follow-up.
• Support continuous improvement of testing processes and quality.

• Minimum 5 years of experience as a Functional Tester.
• Minimum 3 years of demonstrable experience as a Test Specialist.
• Proven experience writing test scenarios.
• Proven knowledge and practical application of formal test methods and techniques.
• Proven experience with Waterfall testing methodology.
• Experience as a tester in an Agile/Scrum project or relevant Agile testing training.
• Proven experience with at least one of the following customer-related processes:
  • Structure
  • Measure
  • Cross-domain
  • Billing
  • Infeed
  • Settlement
• Proven experience with SOAP UI XML and SQL.
• Strong practical experience writing and executing SQL queries.
• Experience reading and understanding Technical Design Documents.
• Proven experience within the Belgian energy sector.
• English at minimum CEFR C1 level with fluent communication skills.
• Dutch or French at minimum CEFR C1 level.
• ISTQB Foundation certification or higher is mandatory and must be included with the application.
• Technical background with the ability to understand integration and application flows.
• Proactive analytical critical and quality-focused mindset.
• Strong communication and collaborative skills.

• Experience with DevOps and VBScript.
• Experience with test automation.
• Willingness and ability to develop skills in more complex SQL queries.
• Experience improving test coverage and testing efficiency.

The successful candidates should be able to work independently while collaborating closely with the wider testing and delivery teams. Candidates are expected to proactively identify quality risks challenge delivered solutions when appropriate learn new business domains and contribute to continuous improvement.

The role requires the ability to work in both Waterfall and Agile/Scrum environments.

• Minimum 2 days per week on-site in Brussels; additional on-site presence may be required depending on project needs.
• Occasional travel to other offices or third-party locations may be required.
• Candidates must provide their own laptop/device with up-to-date security software.
• Candidates must follow the required onboarding and offboarding procedures.
• Strong proficiency in English and either Dutch or French is required.