System Detail Specialist (Lead System Engineer)

The Lead Systems Engineer will play a critical role within a major UK defence IT delivery programme, taking ownership of requirements management, traceability, and the formal acceptance process. The role will act as a key technical and assurance interface between the delivery organisation and the UK Ministry of Defence ensuring that contractual, functional, and non‑functional requirements are fully met, evidenced, and formally accepted.

This position requires a senior engineer with strong systems engineering discipline, experience operating in high‑assurance, regulated environments, and the confidence to engage directly with MOD stakeholders, assurance bodies, and delivery teams.

• Lead the end‑to‑end requirements management lifecycle, from capture and baseline through to verification and acceptance.
• Ensure requirements are clear, testable, traceable, and aligned to contractual and operational needs.
• Maintain robust requirements traceability matrices (RTMs) linking requirements to design, implementation, and test evidence.
• Manage requirements change control in line with programme governance.

• Own and manage the acceptance strategy and acceptance plan for the IT delivery programme.
• Define and agree acceptance criteria with MOD stakeholders.
• Coordinate and oversee acceptance activities, ensuring objective evidence is produced and collated.
• Support formal acceptance events, reviews, and assurance boards.
• Ensure all acceptance evidence is complete, auditable, and compliant with defence standards.

• Act as a primary technical interface with UK MOD representatives.
• Lead technical discussions, reviews, and workshops with MOD stakeholders.
• Provide clear, defensible positions on requirements compliance and acceptance status.
• Support responses to MOD queries, assurance findings, and audit activity.

• Provide technical leadership across systems engineering activities within the programme.
• Ensure systems engineering practices align with recognised standards (e.g. ISO/IEC/IEEE 15288 or equivalent).
• Support integration activities across infrastructure, applications, and security domains.
• Mentor and guide engineers in requirements and acceptance best practice.

• Produce and maintain high‑quality systems engineering documentation, including: Requirements specifications, Acceptance plans and reports, Compliance and traceability artefacts.
• Ensure documentation meets MOD and programme governance standards.
• Contribute to design reviews, readiness reviews, and assurance milestones.

• Proven experience as a Lead or Senior Systems Engineer within defence or highly regulated IT environments.
• Strong background in requirements engineering and acceptance management for large‑scale IT systems.
• Demonstrable experience working directly with the UK MOD or equivalent government bodies.
• Experience delivering IT systems through formal acceptance and assurance processes.
• Strong understanding of systems engineering lifecycle and governance.
• Ability to operate effectively in secure, classified environments.
• Excellent stakeholder management and communication skills.

• Experience with defence IT infrastructure, secure networks, or mission‑critical systems.
• Familiarity with MOD assurance frameworks and delivery governance.
• Experience supporting formal audits or independent assurance reviews.

• Authoritative and credible when engaging senior stakeholders.
• Detail‑driven with a strong focus on evidence and compliance.
• Comfortable operating in complex, high‑pressure delivery environments.
• Pragmatic, structured, and outcome‑focused.

Are you ready to make an impact? Begin your journey of a flourishing and meaningful career, share your CV with us today!

What we do for you: At Leidos we are PASSIONATE about customer success, UNITED as a team and INSPIRED to make a difference. We offer meaningful and engaging careers, a collaborative culture, and support for your career goals, all while nurturing a healthy work-life balance.

We provide an employment package that attracts, develops and retains only the best in talent. Our reward scheme includes: Contributory Pension Scheme, Private Medical Insurance, 33 days Annual Leave (including public and privilege holidays), Access to Flexible benefits (including life assurance, health schemes, gym memberships, annual buy and sell holidays and a cycle to work scheme), Flexi-Time.

Commitment to Diversity: We welcome applications from every part of the community and are committed to a truly diverse and inclusive culture. We foster a sense of belonging, welcoming all perspectives and contributions, and providing equal access to opportunities and resources for everyone. If you have a disability or need any reasonable adjustments during the application and selection stages please let us know, and we will respond in a way that best fits your needs.

Who We Are: Leidos UK & EUROPE – we work to make the world safer, healthier, and more efficient through technology, engineering and science. Leidos is a growing company delivering innovative technology and solutions focused on safeguarding critical capabilities and transformation in frontline services, our work in the United Kingdom includes addressing some of the most complex problems in defence, healthcare, government, safety and security, and transportation.

What Makes Us Different: Purpose: you can use your passion and abilities at Leidos to keep the people you care about safe. We are at the forefront of machine learning, AI, cyber security and solutions. Using your skills in the technology frontline by helping to build a safer world. You can inspire change.

Collaboration: having flexibility to do your job is one of our core benefits, enabling you to become part of our extraordinary team. We have been empowering our people to work flexibly for years. Whether you work from home, the office or on customer sites, we will give you the digital tools and the flexibility to work smarter and align your needs and ours.

People: Leidos empowers people from every background to be themselves and gives you the tools to learn new skills by enabling growth whilst developing. We believe that extraordinary people need opportunities to grow, to be inspired and to inspire others. At Leidos, we invest in technical academies, career rotations and a career development plans that enhance your future.

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail.