During February 2025, Hart contributed to the derailed/cilium repository by implementing a security hardening feature for Kubernetes networking. He focused on aligning CNI configuration file permissions with the CIS Kubernetes Benchmark 1.1.9, ensuring files are written with 0600 permissions to restrict access to the owner and reduce the risk of configuration exposure. This change improved the security posture of the system and provided clear compliance alignment, with the implementation tracked in a dedicated commit. Hart utilized Go for the development work, drawing on his expertise in DevOps, Kubernetes security, and system administration to deliver a focused, compliance-driven enhancement.