anchor.diff:  
     passthru = {
       srcVerification = fetchurl {
  +      failEarly = true;
         inherit (src)
           outputHash
           outputHashAlgo
  
positive.code: }:
  
  let
    version = "1.8.0";
  in
  stdenv.mkDerivation rec {
    name = "intel-vaapi-driver-1.8.0";
  
    src = fetchurl rec {
      urls = [
  
negative.code:         + "libva-intel-driver/${name}.tar.bz2")
      ];
      hashOutput = false;
      sha256 = "efd041602635ce9450fbdf864563d3b95341ef3877337772af708d9cc17b2fce";
    };
  
    nativeBuildInputs = [
  