anchor.diff:    src = fetchurl {
       urls = tarballUrls version;
       hashOutput = false;
  -    sha256 = "9e69a102272324de0bb56025779f84fd44901afcc6eac51505f6a63ea5737ca1";
  +    sha256 = "47f96c37b4f2aac289f0bc1bacfa8bd8b4b209a488d3d15e2229cb6cc9b26449";
     };
   
     buildInputs = [
  
positive.code:   passthru = {
      srcVerification = fetchurl rec {
        failEarly = true;
        urls = tarballUrls "2.4.4";
        pgpsigUrls = map (n: "${n}.sig") urls;
        inherit (gnupg.srcVerification) pgpKeyFingerprints;
        outputHash = "9e69a102272324de0bb56025779f84fd44901afcc6eac51505f6a63ea5737ca1";
        inherit (src) outputHashAlgo;
      };
    };
  
negative.code:     "mirror://gnupg/libassuan/libassuan-${version}.tar.bz2"
    ];
  
    version = "2.5.1";
  in
  stdenv.mkDerivation rec {
    name = "libassuan-${version}";
  