anchor.diff:  }:
   
   let
  -  version = "2.9.9";
  +  version = "2.9.10";
   
     tarballUrls = version: [
       "http://xmlsoft.org/sources/libxml2-${version}.tar.gz"
  
positive.code:     zlib
    ];
  
    propagatedBuildInputs = [
      findXMLCatalogs
    ];
  
    configureFlags = [
      "--with-icu=${icu}"
      "--with-readline=${readline}"
      "--with-zlib=${zlib}"
      "--with-lzma=${xz}"
    ];
  
    passthru = {
      srcVerification = fetchurl rec {
        failEarly = true;
        urls = tarballUrls "2.9.9";
        inherit (src) outputHashAlgo;
        outputHash = "94fb70890143e3c6549f265cee93ec064c80a84c42ad0f23e85ee1fd6540a871";
        fullOpts = {
          pgpsigUrls = map (n: "${n}.asc") urls;
          pgpKeyFingerprint = "C744 15BA 7C9C 7F78 F02E  1DC3 4606 B8A5 DE95 BC1F";
  
negative.code: 
    src = fetchurl {
      urls = tarballUrls version;
      multihash = "QmPWcjgfiucBtkhxoWqJjHcKDXuj7QTmj5qnrCRfxgBJXj";
      hashOutput = false;
      sha256 = "aafee193ffb8fe0c82d4afef6ef91972cbaf5feea100edc2f262750611b4be1f";
    };
  
    buildInputs = [
  