anchor.diff:  
         machine = { pkgs, ... }: {
           environment.systemPackages = [ pkgs."${packageSet}"."${variant}" ];
  -        virtualisation.diskSize = "800";
  +        virtualisation.diskSize = 800;
         };
   
         testScript = ''
  
positive.code: 
    variants = [ "base" "full" "minimal" "staging" "unstable" ];
  
  in listToAttrs (map (makeWineTest "winePackages" [ hello32 ]) variants
    ++ map (makeWineTest "wineWowPackages" [ hello32 hello64 ]) variants)
  
negative.code:               "bash -c 'wine ${exe} 2> >(tee wine-stderr >&2)'"
            )
            assert 'Hello, world!' in greeting
          ''
          # only the full version contains Gecko, but the error is not printed reliably in other variants
          + optionalString (variant == "full") ''
            machine.fail(
                "fgrep 'Could not find Wine Gecko. HTML rendering will be disabled.' wine-stderr"
            )
  