Principal AI Infrastructure Security Engineer

Radiant; United Kingdom; On-site; GBP 90,000 - 130,000; Full time

Job summary

Radiant is seeking a Principal/Staff Security Engineer to join its Infosec team in the UK. This hands-on role reports to the VP Information Security and focuses on securing production environments, firewall policies, Kubernetes, and access controls across data centre operations.

You will build internal penetration testing capability, collaborate with external testers, and work with engineering teams to ensure robust security testing and governance.

Qualifications

• Strong Kubernetes experience and ability to investigate and resolve issues.
• Experience auditing firewall policies and network access controls.
• Experience coordinating penetration testing or conducting tests.
• Comfortable maintaining and operating security tooling and environments on an ongoing basis.
• Strong written communication skills for solo or small team work.
• Experience as the sole security engineer or within a small security team.

Responsibilities

• Audit firewall policies and network access controls across the estate.
• Conduct internal penetration testing, working alongside external partners.
• Build a penetration testing strategy and cadence to improve coverage over time.
• Own and maintain SSO and systems access configuration.
• Document processes, findings and configurations for shared knowledge.

Skills

Kubernetes

Firewall auditing

Penetration testing

Security tooling

Communication

Job description

Radiant is seeking a Principal/Staff Security Engineer to join its Infosec team in the UK. This hands-on role reports to the VP Information Security and focuses on securing production environments, firewall policies, Kubernetes, and access controls across data centre operations.

You will build internal penetration testing capability, collaborate with external testers, and work with engineering teams to ensure robust security testing and governance.