anchor.diff:  let
   
     gsettingsOverridePackages = [
  +    elementary-settings-daemon
  +    epiphany
       gala
  -    epiphany
  -    elementary-settings-daemon
       gnome3.mutter
  +    gsettings-desktop-schemas
       gtk3
       plank
     ] ++ extraGSettingsOverridePackages;
  
positive.code: { stdenv, runCommand, gnome3, elementary-default-settings, nixos-artwork, glib, gala, epiphany, elementary-settings-daemon, gtk3, plank
  , extraGSettingsOverrides ? ""
  , extraGSettingsOverridePackages ? []
  }:
  
negative.code: 
       cat - > $out/share/gsettings-schemas/nixos-gsettings-overrides/glib-2.0/schemas/nixos-defaults.gschema.override <<- EOF
       [org.gnome.desktop.background]
       picture-uri='${nixos-artwork.wallpapers.simple-dark-gray}/share/artwork/gnome/nix-wallpaper-simple-dark-gray.png'
       primary-color='#000000'
  
  