Senior Software Engineer

Senior .NET Developer (C#), Energy Sector  Location: Hybrid, South West London / Surrey border  Salary: £80,000–£85,000 + bonus and benefits  Type: Permanent A growing, independent energy data specialist is looking for a Senior .NET Developer to join its Agile delivery team. You’ll build and evolve secure, high-volume transaction systems that support the UK energy market, part of the country’s critical national infrastructure. This is a hands-on senior role. You’ll design and deliver complex features, shape engineering standards, and mentor others while staying close to the code. What you’ll be doing Designing and building complex features in modern .NET (C#) Turning business and regulatory requirements into robust technical solutions Working with Product Owners on refinement, estimation and sprint planning Leading technical investigations and resolving complex production issues Reviewing code for maintainability, performance and security Contributing to CI/CD pipelines and release automation Supporting secure integrations using certificate-based authentication What we’re looking for 5+ years’ commercial experience with .NET and C# Strong experience building APIs, services and distributed systems Experience with certificate management and secure communications CI/CD, Git-based workflows and containerisation (e.g. Docker) Strong Agile experience, including refinement and estimation Excellent problem-solving and communication skills, with the confidence to mentor others Highly desirable Energy or utilities sector experience AWS or Azure Event-driven or message-based architectures Regulated or high-assurance environments Why apply?  You’ll work on technically complex, real-world systems with genuine influence over architecture and engineering standards, in a collaborative, privately owned business that’s growing.