Worked across uutils/coreutils, nushell, and bat repositories to enhance reliability and correctness of command-line utilities using Rust. Focused on debugging and robust error handling, addressing memory safety in shuf and split, and aligning Unicode and TTY behaviors with GNU standards. Improved input validation and multibyte character handling in pr, and resolved panics in stat, touch, and related utilities. In nushell, fixed grapheme cluster search stability, while in bat, prevented crashes on narrow terminals. Emphasized regression testing and code health, ensuring that all changes reduced crashes and improved user experience for systems relying on stable Rust-based tooling.