anchor.diff:    src = fetchurl {
       urls = tarballUrls version;
       hashOutput = false;
  -    sha256 = "ef75c761858241c6b4372fa6397aa0481a984b84b7b07c4ec7dc2d7b9eee87f8";
  +    sha256 = "679160766401f474731fd60c3aca095f88451e3cc4709b72306e4c34cf981448";
     };
   
     buildInputs = optionals (!isLib) [
  
positive.code:   passthru = {
      srcVerification = fetchurl {
        failEarly = true;
        url = tarballUrls "1.38.0";
        outputHash = "ef75c761858241c6b4372fa6397aa0481a984b84b7b07c4ec7dc2d7b9eee87f8";
        inherit (src)
          outputHashAlgo;
        fullOpts = { };
  
negative.code:     "https://github.com/tatsuhiro-t/nghttp2/releases/download/v${version}/nghttp2-${version}.tar.xz"
    ];
  
    version = "1.39.1";
  in
  stdenv.mkDerivation rec {
    name = "${prefix}nghttp2-${version}";
  