Senior Software Engineer

Senior Software Engineer Based in Stevenage Salary up to £66,000 + Bonus, Overtime, Pension Real-time simulation software. A modern stack. Engineering that actually matters. This isn't a "keep the legacy system limping along" job. You'd be building new simulation software from the ground up, software that tests how some of the most advanced defence technology in the world performs before it ever leaves the ground. If you're fluent in C# (.NET 9) and TypeScript, comfortable across modern frontend frameworks, and you genuinely like owning a problem from UI to distributed backend, this is worth five minutes of your time. What you'd be doing: * Designing and building new features in C# and TypeScript, across Svelte, Angular, Vue or React * Architecting backend systems and working across SQL and NoSQL databases * Running Linux-based CI/CD pipelines (GitLab-CI/Jenkins) for containerised deployments * Mentoring junior engineers and shaping how the team works, not just what it ships * Bringing proper TDD and agile discipline into a team that actually wants to do it right What you'd need: * Strong C# and TypeScript, plus comfort with Docker, GitLab and the npm ecosystem * Solid CS fundamentals, OOP, algorithms, design patterns * C++ or Linux sysadmin experience is a bonus, not a requirement Worth knowing upfront: you'll need British citizenship (or dual UK nationality with British citizenship) for security clearance, and this is largely an on-site role, 4 to 5 days a week depending on workload. If "real-time simulation for next-generation defence systems" sounds more interesting than your current backlog, let's have a conversation, even if you weren't actively looking