anchor.diff:    passthru = {
       srcVerification = fetchurl rec {
         failEarly = true;
  -      urls = tarballUrls "7.50.1";
  +      urls = tarballUrls "7.50.2";
         pgpsigUrls = map (n: "${n}.asc") urls;
         pgpKeyFingerprint = "27ED EAF2 2F3A BCEB 50DB  9A12 5CC9 08FD B71E 12C2";
         inherit (src) outputHashAlgo;
  -      outputHash = "3c12c5f54ccaa1d40abc65d672107dcc75d3e1fcb38c267484334280096e5156";
  +      outputHash = "0c72105df4e9575d68bcf43aea1751056c1d29b1040df6194a49c5ac08f8e233";
       };
     };
   
  
positive.code:     "https://curl.haxx.se/download/curl-${version}.tar.bz2"
    ];
  
    version = "7.50.1";
  in
  stdenv.mkDerivation rec {
    name = "curl${nameSuffix}-${version}";
  
negative.code:   src = fetchurl {
      urls = tarballUrls version;
      hashOutput = false;
      sha256 = "0c72105df4e9575d68bcf43aea1751056c1d29b1040df6194a49c5ac08f8e233";
    };
  
    nativeBuildInputs = [
  