Medior Test Specialist – Freelance

Brussels, Belgium | Hybrid | 2 days on-site per week

Full-time | 2-year assignment | Start date: 9 November 2026

Asenium is looking for four Freelance Medior Test Specialists to join a dedicated testing team on a strategic, long-term assignment.

The project supports a central platform within the Belgian energy market. The team is responsible for preparing and executing the System Acceptance Testing (SAT) scope for major releases. Functional changes are tested manually, while sanity and regression tests are performed using a semi-automated testing tool.

Working under the coordination of an experienced Team Lead and alongside a Senior Test Specialist, you will contribute to structured testing activities across a complex, multi-application environment.

Key responsibilities

-Analyse functional requirements and acceptance criteria.

-Prepare SAT scenarios, test cases and test data.

-Perform manual functional testing and execute semi-automated sanity and regression tests.

-Validate data by writing and executing SQL queries.

-Test services and integrations using SOAP UI and XML.

-Compare vigente results with expected outcomes and document supporting evidence.

-Record defects clearly and ensure appropriate follow-up.

-Perform retesting and non-regression testing.

-Contribute to the first-line analysis of defects reported during major releases.

-Communicate progress, risks, blockers and deviations to the Team Lead.

-Provide functional input to support the external vendor preparing test automation scripts.

-Collaborate with analysts, developers, suppliers and other testing professionals.





-Participate in knowledge-transfer and continuous-improvement activities.

Required profile

-At least 3 years of experience as a Functional Tester, Test Analyst or Test Specialist.

-Experience preparing and executing structured test cases.

-Knowledge of functional, sanity and regression testing.

-Familiarity with formal testing methodologies and techniques.

-Experience in Agile/Scrum or Waterfall environments.

-Practical knowledge of SQL.

-Experience or working knowledge of SOAP UI and XML.

-Ability to understand functional requirements and technical documentation.

-Experience with defect registration and follow-up.

-Strong analytical skills and attention to detail.

-Ability to work effectively within a structured, collaborative testing team.

-English at C1 level or above.

-French or Dutch at C1 level or above.

-Full-time availability and ability to work on-site in Brussels at least two days per week.

Preferred qualifications

-Experience in the Belgian energy sector.

-Knowledge of structure, measure, cross-domain, billing, infeed or settlement processes.

-ISTQB Foundation Level certification or higher.

-Experience with System Acceptance Testing.

-Familiarity with DevOps, VBScript or test automation.

-Experience in international or multilingual environments.

Assignment details

-Number of positions: 4

-Contract: Freelance through Asenium

-Location: Brussels, Belgium

-Working model: Hybrid, with 2 days per week on-site

-Workload: Full-time

-Start date: 9 November 2026

-Duration: 2 years

-Daily rate: To be agreed in euros based on experience

Interested? Please apply with your updated CV, availability, expected daily rate, language proficiency and relevant certifications.

📌 Medior test specialist (España)
🏢 ASENIUM CONSULTING
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