Worked on enhancing the connection lifecycle management in the cloudflare/quiche repository, focusing on optimizing tunnel scenarios such as CONNECT-UDP and MASQUE. Developed features in Rust using asynchronous and network programming techniques to ensure connections are promptly closed when the H3Event receiver is dropped, provided there are no active streams or flows. Introduced logic to prevent unnecessary datagram flow entries when the extended CONNECT feature is disabled, improving resource efficiency. Centralized idle-close functionality into a single method and integrated it across multiple cleanup paths, resulting in more reliable and consistent connection teardown and lifecycle handling for advanced tunneling use cases.