Lead Software Engineer | Defence AI Start-Up | London

Lead Software Engineer | Defence AI Start-Up | London

Lead Software Engineer required to join a rapidly growing London-based defence AI start-up building next-generation autonomous and AI-driven systems supporting critical national security missions.

Founded by experienced operators and technologists, and backed by leading investors, the company is entering an exciting growth phase. This is a hands-on technical leadership opportunity to shape the architecture, mentor engineers, and build highly scalable software powering cutting-edge AI and autonomous systems.

You are:

A Software Engineer with 7+ years of professional experience, strong backend engineering expertise in Python, Java, C++, Rust, or Go, and experience building modern frontends with TypeScript

Comfortable designing and delivering complex, scalable distributed systems

A hands-on technical leader who enjoys mentoring engineers and driving engineering best practices

Language agnostic, with excellent software engineering fundamentals

Comfortable working in fast-paced, high-growth start-up environments

Interested in AI, autonomy, defence, or mission-critical technologies

Bonus points:

Experience within defence, aerospace, robotics, autonomy, or security

Previous experience in an early-stage or venture-backed start-up

Experience building mission-critical or safety-critical systems

Why join:

Build technology that delivers real-world impact within defence and national security

Join a well-backed, high-growth AI start-up with experienced founders

Influence technical direction while remaining deeply hands-on

Work on advanced AI, autonomy, and distributed systems at the cutting edge

Join a small, high-calibre engineering team solving genuinely complex challenges

If you're a hands-on software engineer looking to take technical ownership without moving away from engineering, I'd love to hear from you.

Lead Software Engineer | Defence AI Start-Up | London