The DocBook and CommonMark sources of the NixOS manual are in the nixos/doc/manual subdirectory of the Nixpkgs repository. You can quickly check your edits with the following: $ cd /path/to/nixpkgs $ ./nixos/doc/manual/md-to-db.sh $ nix-build nixos/release.nix -A manual.x86_64-linux If the build succeeds, the manual will be in ./result/share/doc/nixos/index.html. Contributing to the man pages The man pages are written in DocBook which is XML. To see what your edits look like: $ cd /path/to/nixpkgs $ nix-build nixos/release.nix -A manpages.x86_64-linux You can then read the man page you edited by running $ man --manpath=result/share/man nixos-rebuild # Replace nixos-rebuild with the command whose manual you edited If you’re on a different architecture that’s supported by NixOS (check nixos/release.nix) then replace x86_64-linux with the architecture. nix-build will complain otherwise, but should also tell you which architecture you have + the supported ones.