anchor.diff:  { lib, stdenv
   , fetchFromGitHub
  -, fetchpatch
   , nix-update-script
   , pantheon
   , meson
   , ninja
   , pkg-config
  -, vala
  +, vala_0_52
   , desktop-file-utils
   , gtk3
   , libaccounts-glib
  
positive.code:     ninja
      pkg-config
      python3
      vala
      wrapGAppsHook
    ];
  
  
negative.code: 
  stdenv.mkDerivation rec {
    pname = "elementary-photos";
    version = "2.7.2";
  
    repoName = "photos";
  
  