Principal C# Full Stack Engineer – London

About the role

The Principal C# Full Stack Engineer will operate at a strategic level while staying hands‑on, shaping architecture and driving performance‑critical systems for a data‑driven organisation. Based in London, the role offers full onsite work and the chance to influence both technology and business outcomes.

Key responsibilities

• Define and drive architectural decisions across C# and .NET platforms.
• Lead delivery of complex, high‑performance, distributed systems.
• Establish engineering standards and best practices across multiple teams.
• Collaborate with senior leadership on technical strategy and roadmap.
• Mentor senior engineers and support overall team development.

Required profile

• Deep expertise in C# and .NET with a proven engineering track record.
• Experience designing and implementing large‑scale distributed systems.
• Strong understanding of performance engineering and optimisation.
• Ability to influence technical strategy and guide teams.
• Excellent communication and leadership capabilities.

Required skills

• C#
• .NET

What we offer

• Strategic influence within a growing engineering team.
• Opportunity to work on cutting‑edge, complex systems.
• A culture that values autonomy, ownership, and technical excellence.