system_path = pkgs.buildEnv {
      name = "system-path";
      paths = with pkgs; [
        kinit
        opengl_drivers
      ] ++ plasma5;
      pathsToLink =
        [ "/bin"
          "/etc/xdg"
          "/etc/gtk-2.0"
          "/etc/gtk-3.0"
          "/lib" # FIXME: remove and update debug-info.nix
          "/sbin"
          "/share/emacs"
          "/share/nano"
          "/share/org"
          "/share/themes"
          "/share/vim-plugins"
          "/share/vulkan"
          "/share/kservices5"
          "/share/kservicetypes5"
          "/share/kxmlgui5"
          "/share"
        ];
      ignoreCollisions = true;
      # !!! Hacky, should modularise.
      # outputs TODO: note that the tools will often not be linked by default
      postBuild =
        ''
          if [ -x $out/bin/gtk-update-icon-cache -a -f $out/share/icons/hicolor/index.theme ]; then
              $out/bin/gtk-update-icon-cache $out/share/icons/hicolor
          fi
          if [ -x $out/bin/glib-compile-schemas -a -w $out/share/glib-2.0/schemas ]; then
              $out/bin/glib-compile-schemas $out/share/glib-2.0/schemas
          fi
        '';
    };