Product Security Engineer

Staff Product Security Engineer | London

London, UK | Full-Time | SC Clearance Required | UK Citizens Only

We are a defence technology company working on some of the most technically complex systems being built today - AI platforms, command and control systems, aerospace vehicles, and long range sensors. Keeping them secure isn't an afterthought here. It's a core part of how we build.

We're looking for a Staff Product Security Engineer who wants to get their hands dirty developing novel security tooling, hunting vulnerabilities, conducting adversarial testing, and working directly with engineering teams to build resilience into the products themselves.

What you'll be doing:

• Owning the development and maturation of security features across our product suite
• Conducting architecture reviews, source code analysis, configuration audits, and adversarial testing
• Building and integrating security tooling across the product portfolio
• Authoring System Security Plans, Threat Analysis and Risk Assessments, and compliance documentation
• Working alongside engineering, manufacturing, and operations teams to embed security into both products and processes
• Identifying and remediating weaknesses in designs, implementations, and integrations before they become problems

You'll need:

• Proficiency in one or more of C/C++, Golang, Rust, or Python
• Solid experience assessing and improving security across firmware, applications, networks, IoT, or embedded systems
• Experience building and delivering production-ready systems, particularly on embedded or Linux platforms
• Structured threat modelling and risk assessment experience
• UK citizenship and eligibility for SC clearance as a minimum

Great if you also have:

• Familiarity with the UK MOD Cyber Security Model including Def Stans, JSP 440, JSP 453/604, DIPNs and ISNs
• Experience with aviation cyber security standards such as DO-326A/ED-202A
• Knowledge of SORA or CAA/MAA type certification cyber requirements
• Familiarity with RF Emanation Protection or TEMPEST
• Experience with inter-domain gateways, cross domain solutions, or network security devices
• Background in embedded, aerospace, or cyber-physical security architectures
• Sole UK nationality preferred

If you're the kind of engineer who'd rather find the vulnerability than document why someone else missed it - we'd like to hear from you.