Worked on critical backend bug fixes in Go for the istio/istio and envoyproxy/gateway repositories, focusing on networking and TLS/SSL reliability. Addressed a routing issue in istio/istio by refining domain generation logic to correctly handle absolute FQDNs with trailing dots, preventing unintended wildcard fallbacks and improving test coverage for domain handling. In envoyproxy/gateway, resolved a TLS Subject Alternative Name processing bug by ensuring DNS and URI SANs were properly translated and included in upstream TLS configurations, which enhanced certificate matching and security. Both efforts included targeted tests and documentation updates, contributing to more robust and maintainable Kubernetes networking components.