Senior .NET Developer (Previous WinForms)

I'm working with a growing tech-led software business that is heavily investing in its core engineering platform following a recent acquisition. The company is based near Heathrow Airport.

You'll be a Senior C#/.NET Developer taking ownership of a large, business-critical WinForms platform which has recently been migrated from .NET Framework to .NET 8. You'll help evolve the existing application using modern .NET engineering practices, improving its maintainability, automated testing and longer-term technical direction.

The platform currently has limited automated test coverage, so strong practical testing experience is important. The engineering team follows test-first TDD, so you must already have commercial experience working this way.

You'll remain very hands-on with C#/.NET development while also contributing to software design, architecture and technical decisions. You'll work closely with the CTO, Head of Engineering and the original software author, gaining a deep understanding of the platform before helping drive the next phase of its evolution.

Working pattern:

During your initial onboarding and knowledge transfer, you will spend 1-2 weeks onsite immersing yourself into the platform/team and the business. Then you will be remote, with the expectation of being in office once every 1-2 months.

What you'll be doing:

The first 12-18 months will focus on modernising an established WinForms desktop platform running on .NET 8, supporting new business functionality, improving maintainability and introducing stronger engineering practices, automated testing and TDD.

You don't need to be using WinForms in your current role, however you need to be comfortable taking ownership of an existing WinForms codebase and evolve it using modern engineering practices. Beyond that, you'll help shape the future architecture as the platform evolves through APIs, cloud services and modern web technologies.

This is a genuine opportunity to influence technical direction within a collaborative engineering team where your ideas will have a real impact.

Current Technology Stack

C#

.NET Framework

Modern .NET (.NET 8)

WinForms

SQL Server

REST APIs

CI/CD

Automated Testing / TDD

Azure (future direction)

Rea...