anchor.diff:  
     # List packages installed in system profile. To search, run:
     # $ nix search wget
  -  environment.systemPackages = with pkgs; [];
  +  environment.systemPackages = with pkgs; [ xlockmore ];
   
     # Open ports in the firewall.
     # networking.firewall.allowedTCPPorts = [ ... ];
  
positive.code:     # required for bluetooth package
      package = pkgs.pulseaudioFull;
      extraModules = [ pkgs.pulseaudio-modules-bt ];
  
      # TODO: This breaks login
      #configFile = pkgs.writeText "default.pa" ''
        #load-module module-switch-on-connect
      #'';
    };
  
    # X11 XKB key map
    # Mainly Caps -> Ctrl
    services.xserver.xkbOptions = "ctrl:nocaps,caps:none,shift:both_capslock,lv3:rwin_switch,grp:alt_space_toggle,altwin:swap_alt_win";
  
    # Enable touchpad support.
    services.xserver.libinput = {
  
negative.code:   # Bluetooth
    hardware.bluetooth = {
      enable = true;
    };
  
    # Set hosts
  