Worked on the zalando/skipper repository to address a WebSocket upgrade header propagation issue in Go-based backend systems. Focused on HTTP proxy and network programming, the developer fixed a bug where backend response headers were not forwarded to clients during protocol upgrades, particularly for non-101 status responses. The solution involved copying all backend headers to the client response before writing the upgrade status code, ensuring consistent and clear error messages for clients. This change improved reliability and compatibility for client connections, and was reinforced through targeted tests and code reviews, demonstrating a methodical approach to backend development and protocol handling.