Guix System (formerly Guix System Distribution, or GuixSD) is a Linux-based, stateless operating system that is built around the GNU Guix package manager. The operating system provides advanced package management features such as transactional upgrades and roll-backs, reproducible build environments, unprivileged package management, and per-user profiles. It uses low-level mechanisms from the Nix package manager, but packages are defined as native Guile modules, using extensions to the Scheme language.