NixOS > In NixOS, the entire operating system — the kernel, applications, system packages, configuration files, and so on — is built by the Nix package manager

NixOS > In NixOS, the entire operating system — the kernel, applications, system packages, configuration files, and so on — is built by the Nix package manager from a description in a purely functional build language. The fact that it’s purely functional essentially means that building a new configuration cannot overwrite previous configurations. Most of the other features follow from this. > You configure a NixOS system by writing a specification of the functionality that you want on your machine in /etc/nixos/configuration.nix. https://nixos.org/nixos/about.html https://nixos.org/nixos/about.html and GuixSD > The Guix System Distribution supports a consistent whole-system configuration mechanism. By that we mean that all aspects of the global system configuration—such as the available system services, timezone and locale settings, user accounts—are declared in a single place. Such a system configuration can be instantiated—i.e., effected. > One of the advantages of putting all the system configuration under the control of Guix is that it supports transactional system upgrades, and makes it possible to roll-back to a previous system instantiation, should something go wrong with the new one (see Features). Another one is that it makes it easy to replicate the exact same configuration across different machines, or at different points in time, without having to resort to additional administration tools layered on top of the system’s own tools. http://www.gnu.org/software/guix/ http://www.gnu.org/software/guix/ http://www.gnu.org/software/guix/manual/html_node/System-Configuration.html http://www.gnu.org/software/guix/manual/html_node/System-Con...