Senior Developer

Avanti Recruitment is currently partnered with a forward-thinking software business that is in the middle of an exciting technology transformation. They are seeking a Senior .NET Developer to take a leading role in modernising their legacy systems and driving AI adoption across the company.

This is a fantastic opportunity for someone passionate about technology evolution, AI tooling, and delivering clean, modern code. You’ll help replace a VB.NET system with a modern stack (C#, .NET Core, APIs, Cloud) and play a key part in moving the front end towards React.

Beyond the tech upgrade, you’ll become the go-to AI champion within the organisation – helping the team leverage tools like GitHub Copilot and ChatGPT to improve productivity, reduce repetitive work, and introduce smarter development practices. In the long term, you’ll help shape how AI integrates into their internal workflows and potentially their core applications.

What You’ll Be Doing:

• Leading the migration from VB.NET to modern .NET Core, C#, and cloud-based solutions
• Driving the adoption of AI tools across the development team to improve code quality and efficiency
• Helping steer the move to a React front end (already 50% there!)
• Mentoring and supporting other developers while ensuring best practices
• Collaborating with IT and product teams to redesign and modernise core business systems
• Participating in architecture discussions, code reviews, and deployment strategy
• Writing maintainable, well-documented code and implementing scalable solutions

What We’re Looking For:

• 5+ years of .NET development experience, with proven modernisation/migration projects
• Experience moving from legacy systems (VB.NET) to modern stacks
• Strong knowledge of C#, .NET Core, SQL Server, REST APIs, and cloud environments
• Hands-on experience using AI developer tools like GitHub Copilot or ChatGPT
• Passion for clean code, architecture, and technical leadership
• Strong communication skills and a collaborative mindset

Why Join?

• £80,000 – £90,000 base salary annual bonus
• Hybrid working – Brighton or High Holborn (2–3 days per week)
• 25 days holiday bank holidays 2 extra days off
• 5% matched pension
• Private medical cover
• £500 annual allowance for company products
• Bike loans & other perks

This role is perfect for a developer who thrives on modernising systems, wants to become a pioneer in AI-driven development, and enjoys working in a progressive environment where your input drives real change.