Principal Software Engineer

?? Southampton | ?? Permanent | ?? Competitive + Benefits | ?? VC-Backed Scale-Up (Series B, £3.8M)

Are you a senior embedded engineer looking to step into a high-impact technical leadership role?
Join a cutting-edge engineering scale-up developing mission-critical technology for the defence, security, and emergency response sectors.

We're working with a VC-backed business that's developing advanced detection and identification systems - from handheld devices to integrated multi-sensor platforms. With £3.8M in Series B funding and a 25% year-on-year growth rate, this is a great time to join a scaling team making a real-world impact.

• Lead the design and development of complex embedded software systems across Linux and RTOS platforms

• Architect and integrate software with advanced hardware (sensors, FPGAs, RF systems, DSPs)

• Drive quality through CI/CD automation, testing frameworks, and scalable design principles

• Collaborate across engineering, hardware, and product teams to deliver innovative solutions

• Mentor engineers, contribute to sprint planning, and help define technical strategy

• 10+ years' experience in embedded software development (C/C++, Linux, RTOS)

• Strong knowledge of device drivers, low-level systems, and real-time performance optimisation

• Experience with hardware/software integration - ideally with FPGAs, DSPs, or sensor systems

• Proficiency in Python, Git, Docker, and CI/CD tooling (Jenkins, GitLab CI etc.)

• Strong problem-solving mindset and ability to operate in high-trust, cross-functional teams

• Eligible for SC (Security Check) clearance

• Exposure to video/image processing, RF systems, or radiation detection

• Experience with Infrastructure-as-Code tools (Ansible, Terraform, Helm)

• Background in physics or signal processing

• Previous work in defence, aerospace, or security sectors

• On-site in Southampton (collaborative hardware/software environment)

• Be a technical leader in a growing, well-funded deep tech company

• Work on genuinely impactful technology used globally by defence and emergency services

• Join a high-calibre engineering team that values autonomy, rigour, and mission-first thinking

Apply now or message me to learn more - we're moving quickly on this hire.

Spectrum IT Recruitment (South) Limited is acting as an Employment Agency in relation to this vacancy.