Worked on improving the reliability and security of TLS certificate delivery within the istio/istio repository, focusing on ListenerSet configurations deployed with unmanaged parent Gateways. Addressed a critical issue where HTTPS listeners failed to receive authorized TLS certificates during manual deployments, which previously led to authorization failures. The solution involved correcting Service Account computation logic and validating end-to-end certificate propagation for affected ListenerSet scenarios. Documented the behavior change and its impact on incident prevention in release notes. This work leveraged expertise in Go, Istio, and Kubernetes, demonstrating a methodical approach to backend development and secure infrastructure management in cloud-native environments.