Cirrus Selection Limited

Software Engineer - Data Science Based in Bristol Salary up to 65k + Overtime, Bonus, Pension Most software engineers spend their careers shipping incremental updates to things that already exist. This isn't that. This role sits inside a concept programme, which means you're not maintaining a product roadmap, you're helping shape what comes next. You'll be working with complex datasets, building scalable systems with embedded data science capabilities, and translating experimental ideas into production-ready solutions. If that sounds vague, it's intentional. The work is classified. What we can tell you is that it matters, the technical challenges are real, and the people you'll work alongside are genuinely good at what they do. What you'll bring: Strong software engineering fundamentals (C++, Java or similar), a solid grounding in data science or machine learning, and the kind of mindset that's comfortable in ambiguity. You don't need to have all the answers. You do need to be curious enough to find them. Security clearance is required, so British citizenship is essential. If the thought of working on something you can't talk about at dinner sounds more appealing than frustrating, we should speak.

Software Architect Based in Stevenage Salary up to £80,000 + 21% bonus + strong benefits Not every architect role lets you shape something that actually matters. This one does. You ll take ownership of the software architecture behind complex, real-world systems, defining how everything fits together, performs, and scales. Not just diagrams and theory, but architecture that drives delivery. You might already be an Architect. Or you might be the person everyone turns to when the design decisions get difficult. Either way, this is your step up. What you ll be doing: Owning end-to-end software architecture across high-integrity systems Defining structure, interfaces, and real-time behaviour Turning requirements into robust, scalable designs Working closely with engineers, architects, and technical specialists Influencing tools, technologies, and long-term strategy What you ll bring: Strong software design and architecture experience A background in complex or real-time systems Confidence making technical decisions that others rely on Ability to explain the why behind design choices Experience across multiple languages or tech stacks Why this role stands out: Bonus up to 21% Pension up to 14% Clear route into senior / strategic architecture Hybrid working, typically 3 4 days on site Work that genuinely has real-world impact You ll be working at the cutting edge of advanced engineering, building systems where performance, safety, and reliability are non-negotiable. If you re ready to move from contributing to architecture to owning it, this is the move.

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.