anchor.diff:  , fetchFromGitHub
   , nix-update-script
   , fetchpatch
  -, vala
  +, vala_0_54
   , meson
   , ninja
   , pkg-config
  
positive.code:     ninja
      pkg-config
      python3
      vala
      wrapGAppsHook
    ];
  
  
negative.code:   ];
  
    postPatch = ''
      chmod +x meson/post_install.py
      patchShebangs meson/post_install.py
    '';
  