anchor.diff:  # This module generates the nixos-checkout script, which replaces the
   # NixOS and Nixpkgs source trees in /etc/nixos/{nixos,nixpkgs} with
  -# Subversion checkouts.
  +# Git checkouts.
   
   {config, pkgs, ...}:
   
  
positive.code:         mkdir -p "$prefix"
          cd "$prefix"
  
          # Move any old nixos or nixpkgs directories out of the way.
          backupTimestamp=$(date "+%Y%m%d%H%M%S")
  
  
negative.code:         fi
  
          # Check out the NixOS and Nixpkgs sources.
          git clone git://github.com/NixOS/nixos.git nixos
          git clone git://github.com/NixOS/nixpkgs.git nixpkgs
        '';
     };
  
  in
  
  {
    environment.systemPackages = [ nixosCheckout ];
  }
  