Senior .Net Developer

Function

Our client is seeking a senior .NET professional to support the migration and modernization of several critical information tools that underpin core business processes. This opportunity is ideal for someone who combines strong technical depth with a hands-on mindset, and who can help ensure the quality, performance, and long-term sustainability of business-critical software solutions.

Responsibilities

• Contribute actively to the development of software components in .NET Framework and .NET Core.
• Design scalable technical solutions in collaboration with the architecture team.
• Translate functional requirements into robust technical solutions together with analysts.
• Carry out code reviews and promote strong development practices across the team.
• Support team members through technical coaching and mentoring.
• Safeguard the quality, performance, security, and maintainability of applications.
• Contribute to system performance optimisation and the evaluation of new technologies aligned with business goals.

Technical Skills

• Strong expertise in C# and .NET Core / .NET 10.
• Hands-on experience with ASP.NET Web API, MVC, and Blazor.
• Solid knowledge of authentication and authorisation concepts, including JWT, OIDC, and claims-based security.
• Experience with Entity Framework Core and SQL Server.
• Good understanding of REST APIs and Swagger/OpenAPI.
• Experience with unit and integration testing.

Profile

• Strong analytical thinking and the ability to process and integrate complex information.
• Structured, solution-oriented mindset with the ability to identify practical alternatives.
• Technical leadership skills and a collaborative approach.
• Resilient and adaptable when facing technical or contextual change.
• Comfortable guiding others and contributing to a culture of excellence.

Practical Information

• Language requirements: fluent in one of the two national languages, French or Dutch, at C2 level, and very good English at C1 level.
• The role requires working from the office in Brussels at least twice per week.
• Teleworking is possible within Belgium.

Contactperson & Reference

• Reference #: INW27470
• Pieter Messely
• pieter.messely@i4m.be