About the Mission

Version EN Function As a Senior .NET Developer, you play a key role in the design, development and maintenance of robust software solutions based on Microsoft technologies. You bring your technical expertise to guarantee the quality of the code, the sustainability of the solutions and the performance of the systems. You are also a technical mentor to other team members. Responsibilities Actively participate in the development of software components in .NET (Framework and Core); Design scalable technical solutions in collaboration with the architecture team; Technically supervise team members and foster a culture of excellence; Carry out code reviews and ensure compliance with good development practices; Analyze functional needs with analysts and translate them into technical solutions; Ensure the quality, performance, security and maintainability of applications; Participate in optimizing system performance; Integrate and evaluate new technologies in line with business objectives. Behavioral skills Ability to critically analyze and integrate information; Structured and solution-oriented thinking; Ability to generate viable alternatives and draw relevant conclusions; Technical leadership and collaborative spirit; Resilience and adaptability in the face of technical or contextual changes Language skills: ·         Proficiency in one of the two national languages: FR or NL (level C2*)·         Very good level of English (level C1*)*The levels indicated correspond to the Common European Framework of Reference for Languages ​​(CEFR), which defines the standards of language proficiency in Europe. We offer youn interesting job in the provision of ICT and Data services which has an impact on society, with numerous advantages: ·         A good balance between professional and private life; Flexible schedule in the provision of 40 hours per week (7:30 a.m. to 8 p.m. with fixed times between 9 a.m. and 12 p.m. and 1 p.m. and 4 p.m.); Possibility of teleworking; Workspaces organized according to activities; Easy accessibility via public transport common; Car and bicycle parking in the building; Individual locker; Company restaurant; NL VERSIE FunctieAls Senior .NET Developer speel je een sleutelrol bij het wetwerpen, ontwikkelen en onderhouden van robuste software oplossingen op base van Microsoft technologiesën. I provide technical expertise, guarantee code knowledge and support the technical mentor of your team. Verantwoordelijkheden Actief deelnemen aan de ontwikkeling van software components in .NET (Framework en Core); Ontwerpen van schaalbare en onderhoudbare oplossingen en samenwerking met dearchitectuurteam; Technical coaching involves a team led by an excellent culture; Use code reviews and find out about best practices; Analyze the functions being performed and analyzed in technical operation; Zorgen voor de kwaliteit, services, beveiliging en onderhoudbaarheid van toepassingen; Optimize your system requirements; Evaluate the integration of new technologies that pass through bedrijfsdoelstellingen. Gedragsvaardigheden Kritische informatieanalyse en integratie; Gestructureerdand solution-oriented thinking; Creative in coming up with alternatives and drawing correct conclusions; Technical leadership and collaboration; Resilience and adaptability to technical or contextual changes. Language skills: Fluent in one of the two national languages: FR or NL (level C2*)  Very good level of English (level C1*)*The levels indicated correspond to the European Framework of Reference for Languages ​​(CEFR), which sets the standards for language proficiency in Europe. We offer you an interesting job in ICT and Data services that has an impact on society, with many advantages: ·         A good balance between work and private life; Flexible working hours of 40 hours per week (7:30 am to 8:00 pm with fixed periods between 9:00 am and 12:00 pm, 1:00 pm and 4:00 pm); The possibility of teleworking; Workplaces organized according to activities; Good accessibility to public transport transportation; Parking for cars and bicycles in the building; Individual lockers; Company restaurant; ·         Various opportunities for self-development: training and internship opportunities (can be followed outside working hours) via our e-academy self-training platform or via the Microsoft Enterprise Skills Initiative platform.

Required Skills

ASP .NET Web API, Authentication/Authorization (JWT, OIDC, claims), Blazor, C# / .NET (Core, 10), Entity Framework Core, MVC, REST API’s, REST, Swagger/OpenAPI, SQL Server, Testing (unit + integration)

Practical Information

  • Company: Confidential
  • Location: Brussel – Hybrid
  • Start Date: 29 June 2026
  • End Date: 31 December 2026
  • Duration: 7 months
  • Contract Type: Freelance / Mission
  • Application Deadline: 18 June 2026