ss_pak_extract(1) on Linux
The text 90ff4bcbaa57, as Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy) shipped it. The page shows this text now.
Tool for reading general PAK files (used by Singstar)