The GNU project has announced the release of coreutils 9.9, a new stable version of the essential collection of basic file, shell, and text manipulation utilities that form the backbone of nearly every Linux and Unix-like system.

Among the most notable fixes, the cp command regains proper performance when handling transparently compressed files, a regression observed with OpenZFS and similar filesystems.

At the same time, the tail utility now correctly outputs the requested number of lines for non-small -n values, while unexpand no longer triggers heap buffer overflows when using the GNU-specific /NUM or +NUM formats with --tabs.

Other fixes address subtle behavioral issues in tools like numfmt, sort, and cksum, ensuring correct operation when working with various data encodings, locales, and compression setups.