Principal Architect (DV Security Clearance)

CGI Group Inc.; Devizes; On-site; GBP 90,000 - 130,000; Full time

Job summary

CGI is seeking a Principal/Lead Architect for a complex, secure defence software system based in Chippenham, onsite five days a week. You will Own and evolve the overall solution architecture and act as technical authority, aligning with operational needs.

You will lead, coach and mentor architects and engineers, establish architecture governance and ensure design principles, security and resilience across software, data and deployment environments.

Qualifications

• Proven experience as Principal Architect or similar on complex software systems.
• Experience leading architects, engineers or multidisciplinary technical teams.
• Experience owning or shaping architecture of systems with scientific, engineering or algorithmic components.
• Experience establishing architecture governance, design assurance and decision-making frameworks.
• Experience in secure, regulated, or operationally sensitive environments.
• Strong stakeholder engagement with executive and client stakeholders, including ability to explain complex issues to non-technical audiences.

Responsibilities

• Provide principal architectural leadership and act as technical authority for a complex, secure defence software system.
• Own and evolve the overall solution architecture, ensuring resilience, security, maintainability and alignment to operational needs.
• Work with senior stakeholders internal and external to the project, ensuring technology perspectives are accurately represented.
• Lead, coach and mentor architects, technical leads and engineers, building capability across the team.
• Establish and run architecture governance, including design principles, decision records and escalation routes.
• Translate client needs and technical drivers into coherent designs, roadmaps and delivery priorities.
• Guide architectural decisions across software, integration, data, tooling, environments and service operations.
• Support delivery practices, DevSecOps adoption and ways of working.
• Ensure solutions meet security, assurance, resilience, and operational continuity requirements.

Skills

Architecture leadership

Stakeholder engagement

Security architecture

Governance

DevSecOps

Mentoring

Complex software

Regulated environments

Scientific modelling

Non-technical explain

Job description

The Space, Defence and Intelligence business unit in CGI is a true IT Systems Integrator. We work, build, and operate bespoke, technically complex, mission-critical systems which help our clients keep us all safe and secure. We bring innovation to our clients using proven and emerging technologies, agile delivery processes and our deep expertise across the breadth of space, defence, intelligence, aerospace and maritime, all underpinned by our end-to-end cyber capability. We work collaboratively with global technology companies, cutting edge SMEs and academia to deliver the optimal solution for each client. CGI was recognised in the Sunday Times Best Places to Work List 2025 and has been named one of the 'World's Best Employers' by Forbes magazine. We offer a competitive salary, excellent pension, private healthcare, plus a share scheme (3.5% + 3.5% matching) which makes you a CGI Partner not just an employee. We are committed to inclusivity, building a genuinely diverse community of tech talent and inspiring everyone to pursue careers in our sector, including our Armed Forces, and are proud to hold a Gold Award in recognition of our support of the Armed Forces Corporate Covenant. Join us and you'll be part of an open, friendly community of experts. We'll train and support you in taking your career wherever you want it to go. Working closely with client stakeholders, delivery leaders, engineers and subject matter experts, you will help shape the overall approach for the engagement from a technology and process perspective focusing on the outcomes and value the client seeks. To support this, you will establish effective architecture governance, guide the approach and methodologies across solution architecture, infrastructure, technical architecture, security architecture and the operating model for delivery. You will work to support continuous improvement by identifying areas of opportunity and help introduce innovation in a controlled and pragmatic way within a secure defence environment. Due to the secure nature of the programme, you must be a sole UK National and currently hold UK Higher Level Clearance. This position will require you to be onsite in Chippenham 5 days per week. Your future duties and responsibilities

Key responsibilities include:

• Provide principal architectural leadership and act as technical authority or design authority for a complex, secure defence software system.
• Own and evolve the overall solution architecture, ensuring it remains resilient, secure, maintainable and aligned to operational needs.
• Work with senior stakeholders both internal and external to the project, ensuring that the project and solution is accurately represented from a technology and methodology perspective.
• Lead, coach and mentor architects, technical leads, engineers and subject matter experts, building technical capability and confidence across the team.
• Establish and run effective architecture governance, including design principles, decision records, technical assurance, review forums and escalation routes.
• Understand and interpret requirements involving complex mathematics, physics, scientific modelling and operational constraints.
• Translate client needs, mission outcomes and technical drivers into coherent architectural designs, roadmaps and delivery priorities.
• Guide architectural decisions across software, integration, data, tooling, environments, deployment approaches and service operations.
• Support delivery methodology, helping teams improve engineering practices, quality, governance, DevSecOps adoption and ways of working.
• Ensure solutions meet security, assurance, resilience, maintainability and operational continuity requirements.

Essential experience and skills:

• Proven experience as a Principal Architect, Lead Architect, Chief Architect, Design Authority or Senior Solution Architect on complex software intensive systems.
• Experience leading, coaching or developing architects, technical leads, engineers or multidisciplinary technical teams.
• Experience with people management, technical capability development, communities of practice, recruitment or succession planning.
• Experience owning or shaping the architecture of systems involving scientific, engineering, mathematical, physics based or algorithmic components.
• Experience establishing architecture governance, technical standards, design assurance and decision making frameworks.
• Experience working in secure, regulated or operationally sensitive environments.
• Strong senior stakeholder engagement skills, including with executive, senior military or equivalent client stakeholders, including the ability to explain complex technical issues clearly to non technical audiences.

Desirable experience:

• Defence, maritime, submarine, nuclear, targeting, command and control or mission critical systems experience.
• Experience with legacy system sustainment, modernisation, transition or service evolution.
• Experience working in Agile, DevOps or DevSecOps delivery environments.
• Experience introducing innovation, automation, AI, data exploitation or improved tooling into secure environments.
• Experience supporting bids, solution shaping, technical strategy or client advisory activity for defence clients.

#LI-FP1 Together, as owners, let's turn meaningful insights into action.

Life at CGI is rooted in ownership, teamwork, respect and belonging. Here, you'll reach your full potential because... You are invited to be an owner from day 1 as we work together to bring our Dream to life. That's why we call ourselves CGI Partners rather than employees. We benefit from our collective success and actively shape our company's strategy and direction. Your work creates value. You'll develop innovative solutions and build relationships with teammates and clients while accessing global capabilities to scale your ideas, embrace new opportunities, and benefit from expansive industry and technology expertise. You'll shape your career by joining a company built to grow and last. You will be supported by leaders that care about your health and well-being and provide you with opportunities to deepen your skills and broaden your horizons. That same commitment to fairness extends to how we use technology. To support our recruitment team, AI tools may be used to help assess applications though they never replace human judgement. All hiring decisions remain entirely in the hands of our recruitment professionals. Come join our team-one of the largest IT and business consulting services firms in the world.