Lead Security Architect in Portsmouth

Job DescriptionLead Security Architect (Defence DevSecOps and AI/ML)Location: PortsmouthWorking model: Remote 50% and 50% onsiteStart date: approx. 24/08/2026Duration: 23/11/2026Rate: £640 to £700 inside IR35 through an FCSA approved umbrellaActive MOD SC clearance and sole UK is required for consideration.Mission: Own security architecture and the integration roadmap for AI/ML across multi-cloud and edge; align to client IT/cloud strategy and UK Defence priorities; enable secure multinational collaboration and high-side code promotions with repeatable assurance. Manage the Secure by Design elements of the project and own the assurance process end to end.Key ResponsibilitiesLead the Security elements of the program across different use cases for AI/ML development and trials.Chair Security Working groups and tri-nation collaboration.Manage security visibility and outcomes, manage senior stakeholder engagement.Threat and risk management; translate ambiguous requirements into testable

controls.Define classification-aware architectures, trust boundaries, cross-domain data movement guardrails.Provide Security guidance and controls for complex program.Lead Security roadmap: DevSecOps, policy-as-code controls, risk-based CI/CD gates.Govern supply-chain security: artefact signing, SBOMs, provenance; adopt SLSA-style controls.Reduced lead time to secure release; zero-critical promotion checkpoints; supplier onboarding efficiency; executive risk communication.Mentor juniorsExperience & Qualifications5+ years in Cyber Security, proven multi-cloud/edge architecture.Defence experience; familiarity with UK guidance; at least MOD SC cleared and UK Sole .Certifications: CISSP (equivalent), TOGAFKey AttributesThis role requires essential skills of adaptability and a pragmatic and positive attitude towards security as a business enabler, the technical skills and aptitudes can be learned from the team.TPBN1_UKTJ