Lead Security Architect

Lead Security Architect (Defence DevSecOps and AI/ML)

Location: Portsmouth

Working model: Remote 50% and 50% onsite

Start date: approx. 24/08/2026

Duration: 23/11/2026

Rate: £640 to £700 inside IR35 through an FCSA approved umbrella

Active MOD SC clearance and sole UK Nationality 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 Responsibilities

• Lead 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 juniors

Experience & Qualifications

• 5+ years in Cyber Security, proven multi-cloud/edge architecture.
• Defence experience; familiarity with UK guidance; at least MOD SC cleared and UK Sole national.
• Certifications: CISSP (equivalent), TOGAF

Key Attributes

This 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.