Principal Solution Architect - Defence & National Security

Are you an experienced Solution Lead or Enterprise Architect with a background in highly secure environments? Do you bring defence or national security experience, strong architecture expertise, and a practical, innovative approach to solving complex challenges? If so, we’d like to hear from you.

As Principal Solution Architect, you will play a key role in shaping and delivering enterprise solutions for defence and national security customers. Working with the Office of the CTO, you will combine future-focused innovation with hands-on leadership across existing customer engagements.

This role is split across two core areas:

Innovation & Future Solutions (50%) lead the identification, design, and development of secure, IT-enabled solutions that respond to the evolving needs of clients and the wider sector.

Short-term Customer Initiatives (50%) provide enterprise and solution leadership for rapid reviews, recovery activity, and complex customer challenges, helping to resolve issues and support successful delivery outcomes.

This is a UK-based role, with travel required to client sites along the M4 corridor.

What you will be doing:

• Lead the design and delivery of secure enterprise and solution architectures for defence and national security clients.
• Shape innovative, IT-enabled solutions that respond to emerging client and sector needs.
• Provide solution leadership for short-term assessments, remediation activity, and complex customer initiatives.
• Build strong working relationships with clients, partners, and internal teams to support successful delivery.
• Contribute to business growth through pre-sales support, market insight, and representation of Sopra Steria’s capabilities.
• Identify and manage risks, while sharing knowledge through mentoring, workshops, and collaboration.

• Experience as a Solution Lead, Enterprise Architect, or in a similar role within highly secure defence or national security environments.
• Strong understanding of defence customers, suppliers, and delivery contexts, including MOD and/or UKIC.
• Proven ability to design and lead complex solutions across COTS, custom, and enterprise-scale environments.
• Expertise in architecture approaches and tools such as TOGAF, ArchiMate, and C4, with a secure-by-design mindset.
• Experience working in agile delivery environments, with knowledge of modern software delivery and DevSecOps practices.
• Confidence working with senior stakeholders, balancing strategic thinking with practical support to drive delivery success.

Sopra Steria’s Aerospace, Defence and Security business designs, develops and deploys digital solutions to Central Government clients. The work we do makes a real difference to the client’s goal of National Security, and we operate in a unique and privileged environment. We are given time for professional development activities, and we coach and mentor our colleagues, sharing knowledge and learning from each other. We cultivate a culture in which employees feel valued and supported and have pride in their work for the customer, delivering outstanding rates of customer satisfaction in the UK’s most sophisticated safety- and security-critical markets.