anchor.diff:  
   stdenv.mkDerivation rec {
     pname = "yelp";
  -  version = "41.2";
  +  version = "42.beta";
   
     src = fetchurl {
       url = "mirror://gnome/sources/yelp/${lib.versions.major version}/${pname}-${version}.tar.xz";
  -    sha256 = "sha256-sAvwM/At15ttPyVQMccd+NbtOOVSyHC485GjdHJMQ8U=";
  +    sha256 = "sha256-cT187uTnI9ECP6Ox4HN4MUcZKRctNGhC/tBHFO6zkK8=";
     };
   
     nativeBuildInputs = [
  
positive.code: 
    buildInputs = [
      gtk3
      glib
      webkitgtk
      sqlite
  
negative.code: , webkitgtk
  , pkg-config
  , gtk3
  , libhandy
  , glib
  , gnome
  , sqlite
  