anchor.diff:        gnome3.eog
         gnome3.dconf
         i3lock-color
  +      compton
  +      dunst      
         feh
  +      polybar
         rofi
         arc-theme
         papirus-icon-theme
  
positive.code:     };
      windowManager = {
        i3.enable = true;
      };
    };
    # services.xserver.xkbOptions = "eurosign:e";
  
negative.code:       startAgent = true;
      };
    };
    nixpkgs.config = {
      allowUnfree = true;
      packageOverrides = pkgs: rec {
        polybar = pkgs.polybar.override {
          i3GapsSupport = true;
          mpdSupport = true;
          alsaSupport = true;
          pulseSupport = true;
          nlSupport = true;
        };
      };
    };
    # Enable sound.
    sound.enable = true;
    hardware.pulseaudio.enable = true;
  