Custom software in C# & .NET
20 years of intensive hands-on work with the Microsoft ecosystem. Robust business applications, high-performance backend services and user-friendly WPF interfaces — tailored to your business.
Independent developer based in Valenciennes — I work with companies in the Nord, the Hauts-de-France region and throughout France, on-site or remotely.
What I build
- Custom business applications and ERPs
- User-friendly, high-performance WPF interfaces
- Windows services and scheduled tasks
- REST APIs with ASP.NET Core
- ETL data integration: Semarchy xDI (formerly Stambia)
- Mirakl marketplace connectors for retail and e-commerce
- Migration from .NET Framework to .NET Core and legacy systems
- Reusable libraries and components
The stack
A mature ecosystem with proven performance.
Strong typing & testing
C#'s static typing and the testing culture of the .NET ecosystem ensure reliable, maintainable code over the long term.
Ultra-fast .NET 8+
The latest versions of .NET are among the fastest runtimes on the market — ideal for high-load services.
Guaranteed longevity
Microsoft maintains .NET for the long haul. Your investment stays protected and the code can easily be picked up by another developer.
Frequently asked questions about .NET development
What types of applications do you build in .NET/C#? +
I build custom business software (WPF, WinForms), Windows services, REST APIs with ASP.NET Core, desktop applications, data integration tools (ETL/Stambia) and migrations of legacy systems to modern architectures. For retail, I also work on freelance retail data integration: catalogue feeds, orders and marketplace connectors.
How long does a typical .NET project take? +
A module or feature generally takes 2 to 8 weeks. A complete piece of software can require 3 to 12 months depending on complexity. I start with a precise scoping phase to estimate the scope and timeline before any commitment.
Can you take over and evolve an existing C# project? +
Yes, it's a big part of what I do. I start with an audit of the existing code to identify the risks, technical debt and areas for improvement. I can then take over the project seamlessly, without starting from scratch.
Is .NET still relevant against newer technologies? +
.NET 8/9 is one of the highest-performing runtimes on the market. Microsoft invests heavily in the platform, which now covers desktop, web, cloud, mobile and AI. It's a future-proof choice for strategic projects.