NixOS
NixOS is an independently developed GNU/Linux distribution that aims to improve the state of the art in system configuration management. In NixOS, the entire operating system, including the kernel, applications, system packages and configuration files, are built by the Nix package manager.
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blendOS
blendOS is an Arch Linux-based, rolling-release distribution which automates installing software from supported distributions (Arch Linux, Fedora and Ubuntu) into containers. blendOS tries to make software management in across containers feel native and provides access to the user's home directory for each container.