Principal Software Engineer (Backend & Platform)

In this role you will lead the design and development of an internal developer platform used by all engineering teams. You will own tooling, infrastructure, and workflows, and drive platform-wide architectural decisions. You will implement agentic AI within engineering workflows and establish guardrails, monitoring, and governance. This hands-on principal role offers significant technical ownership to set standards and accelerate innovation, with a hybrid Bristol-based schedule and UK SC clearance eligibility as prerequisites.

• Lead design, architecture and development of the internal developer platform.
• Own tooling, infrastructure, and workflows used by engineering teams.
• Implement agentic AI in real engineering workflows and drive rollout across pipelines.
• Design and enforce guardrails for agentic AI (sandboxing, permissions, audit logging, observability).
• Maintain deep hands-on work with CI/CD, infrastructure as code, containers, and Kubernetes.
• Build and deploy reproducible development environments.
• Set technical direction and standards to drive innovation.

• Substantial experience as a principal or staff software engineer.
• Proficiency with multiple languages/tools/frameworks (Python, Go, Rust, AWS, Kubernetes, etc).
• Experience building developer platforms and internal tooling.
• Hands-on experience implementing agentic AI in real engineering workflows.
• Experience designing AI guardrails (sandboxing, permissioning, audit logging, observability).
• Deep hands-on experience with CI/CD, infrastructure as code, containers, and Kubernetes.
• Experience building and deploying reproducible development environments.
• Eligibility for UK SC clearance.

• leadership
• collaboration
• clear communication
• Python
• Go
• Rust