Worked on the tokio-rs/tokio repository to enhance runtime shutdown error handling by making the is_rt_shutdown_err function publicly accessible. This change allows external systems to check for shutdown-related errors, improving observability and reducing debugging time in production environments. The approach involved designing a public API in Rust and developing comprehensive tests to cover various shutdown error scenarios, ensuring robust error handling and preventing regressions. Focused on error handling, testing, and public API design, the work strengthened the visibility of runtime shutdown states and contributed to more maintainable and reliable production deployments without introducing new bug fixes during the period.