anchor.diff:    postInstall = ''
       for prog in "$out/bin/julia" "$out/bin/julia-debug"; do
           wrapProgram "$prog" \
  -            --prefix LD_LIBRARY_PATH : "$LD_LIBRARY_PATH" \
  +            --prefix LD_LIBRARY_PATH : "$LD_LIBRARY_PATH:$out/lib/julia" \
               --prefix PATH : "${stdenv.lib.makeBinPath [ curl ]}"
       done
     '';
  
positive.code: 
  stdenv.mkDerivation rec {
    pname = "julia";
    version = "0.5.0-dev-2016-06-10";
    name = "${pname}-${version}";
  
    src = fetchgit {
      url = "https://github.com/JuliaLang/${pname}";
      rev = "56d7d6672c7db717dacb5e34f485180c2eba83b2";
      sha256 = "1wbrzdrxp94i7yxdgf3qgrjshmqxi0c4bqz7wy0c0c0kjlg6flmx";
    };
  
    prePatch = ''
  
negative.code:     sha256 = "03kaqbjbi6viz0n33dk5jlf6ayxqlsq4804n7kwkndiga9s4hd42";
    };
  
    libuvVersion = "8d5131b6c1595920dd30644cd1435b4f344b46c8";
    libuv = fetchurl {
      url = "https://api.github.com/repos/JuliaLang/libuv/tarball/${libuvVersion}";
      sha256 = "1886r04igcs0k24sbb61wn10f8ki35c39jsnc5djv3rg4hvn9l49";
    };
  
    rmathVersion = "0.1";
  