
The use of Nix 2.0 significantly simplifies the installer, since we can just pass a different store URI (--store /mnt) - it's no longer needed to set up a chroot environment for the build, and to bootstrap Nix into the chroot. Also, commands that need to run in the installation (namely boot loader installation and setting a root password) are now executed using nixos-enter. This also removes the need for nixos-prepare-root since any required initialisation is done by Nix or by the activation script.
To build the manual, you need Nix installed on your system (no need for NixOS). To install Nix, follow the instructions at https://nixos.org/nix/download.html When you have Nix on your system, in the root directory of the project (i.e., `nixpkgs`), run: nix-build nixos/release.nix -A manual.x86_64-linux When this command successfully finishes, it will tell you where the manual got generated.