Full job descriptionAvanti is working with an established software business that is investing heavily in the modernisation of one of it’s core platforms and is looking for a Senior Fullstack .NET Developer with strong experience in React.
This is a hands-on engineering role where you’ll help evolve an established business-critical application into a more modern, scalable architecture.
The focus will be on improving the underlying platform, building modern services and APIs, increasing automated test coverage and gradually moving functionality towards a modern web-based frontend.
You’ll remain very hands-on with C#/.NET development while also contributing to software design, architecture and technical decisions across the wider engineering team.
The business places a strong emphasis on the engineering quality, automated testing and test-first development, so strong TDD experience is essential.
What you’ll be doing
*Building and maintaining applications and services using C# and modern .NET
*Designing and developing REST APIs
*Developing frontend functionality using React
*Helping modernise an established application architecture
*Improving automated test coverage and overall code quality
*Working in a test-first development environment
*Contributing to software design and architecture decisions
*Improving platform maintainability, scalability and long-term technical direction
*Supporting existing systems while helping build their future replacement


Technology Environment:
*C# / .NET 8
*REST APIs
*React
*SQL Server
*Automated testing
*TDD
*CI/CD
*Cloud technologies


There is also some exposure to established desktop WinForms technologies within the existing platform, although previous experience in this area is not essential.
Essential Skills:
*Strong C#/.NET
*React
*TDD
*REST APIs
*CI/CD knowledge
*Experience contributing to architecture / design and technical decisions
*Ability to work independently and take ownership of technical problems
Experience with cloud platforms, legacy application modernisation or AI-assisted development would be useful.
Working arrangement
The role is remote first, with some initial time spent with the team during onboarding, and occasional in person collaboration thereafter (West London / M4 corridor) – costs covered.
Interview process
The process will involve an initial video call which will be a technical discussion, followed by a final-stage video interview including a practical coding element following TDD.
Package
Salary up to £70,000, plus pension, holiday allowance and additional employee benefits.
If interested in the position then click Apply Now!!