anchor.diff:  }:
   
   let
  -  version = "19.0.0";
  +  version = "19.0.2";
     truffleMake = ./truffle.make;
     R = fetchurl {
       url = "http://cran.rstudio.com/src/base/R-3/R-3.5.1.tar.gz";
  
positive.code:       owner  = "oracle";
        repo   = "graal";
        rev    = "vm-${version}";
        sha256 = "1yimynf1x1wdp8y7rrw3ygpzv6p92n186wg22vh0zyhczl8w6x4f";
      };
      patches = [ ./002_setjmp.c.patch ./003_mx_truffle.py.patch ];
      buildInputs = [ mx zlib mercurial jvmci8 git clang llvm
  
negative.code: in rec {
  
    mx = stdenv.mkDerivation rec {
      version = "5.224.1";
      pname = "mx";
      src = fetchFromGitHub {
        owner  = "graalvm";
        repo   = "mx";
        rev    = version;
        sha256 = "1gf8fbzn6mfg3p71mxx89ks4n6zlr6ia9zj2sq0dflp4aa0acx6q";
      };
      nativeBuildInputs = [ makeWrapper ];
      prePatch = ''
  