Freelance Senior .NET / WinForms Developer

Company

This large Belgian organization manages an extensive, technically complex and business-critical network. Behind the scenes, reliable IT systems support operational processes where stability, continuity and long-term maintainability are essential.

Within this enterprise environment, significant investments are being made in the modernization of existing applications and the further evolution of the overall IT architecture. You will join an experienced team where quality, autonomy, technical ownership and clear communication are central.

Responsibilities

You will take end-to-end ownership of an existing business-critical application and ensure a smooth technical handover from the current developer. Your first focus will be to understand the current application landscape, analyze the existing codebase and document the architecture, dependencies and technical risks in a clear and structured way.

The application is currently built in a legacy .NET Framework / Windows Forms environment, so you will be responsible for stabilizing, maintaining and improving a non-standard FAT client application with limited documentation. You will identify technical debt, assess risks related to stability, security and maintainability, and define the best evolution strategy: targeted fixes, incremental improvements, partial refactoring or, if needed, a broader rewrite.

Beyond analysis, you will also implement bug fixes, improvements and new evolutions where required. You will collaborate closely with the current developer, ICT teams and business stakeholders to ensure continuity and make well-founded technical decisions. This role requires strong autonomy, the ability to bring structure into complexity and the confidence to take ownership in a legacy environment.

Profile

• Bachelor’s or Master’s degree in IT (or equivalent through strong experience)
• Senior professional experience with .NET
• Good knowledge of WinForms/Windows Forms
• Angular experience is a very big asset
• You're a pragmatic team player
• You work in English and understand Dutch & French

Offer

• A freelance role within a well-established organisation
• A long-term assignment with renewable year contracts (+5 years total)
• Stability at a reliable employer & networking opportunities
• 3 days of home working, 5-10 minute walk from the train station

Interested?

[email protected]