anchor.diff:      for comp in contrib/jdk* contrib/polyml-* contrib/z3-* contrib/verit-* contrib/vampire-* contrib/e-*; do
         rm -rf $comp/x86*
       done
  +
  +    substituteInPlace lib/Tools/env \
  +      --replace /usr/bin/env ${coreutils}/bin/env
  +
  +    rm -r heaps
     '' + (if ! stdenv.isLinux then "" else ''
       arch=${if stdenv.hostPlatform.system == "x86_64-linux" then "x86_64-linux" else "x86-linux"}
       for f in contrib/*/$arch/{bash_process,epclextract,nunchaku,SPASS,zipperposition}; do
  
positive.code: { lib, stdenv, fetchurl, nettools, java, polyml, z3, veriT, vampire, eprover-ho, rlwrap, makeDesktopItem }:
  # nettools needed for hostname
  
  stdenv.mkDerivation rec {
  
negative.code:       patchelf --set-rpath "${lib.concatStringsSep ":" [ "${java}/lib/openjdk/lib/server" "${stdenv.cc.cc.lib}/lib" ]}" $d/*.so
      done
    '');
  
    buildPhase = ''
      export HOME=$TMP # The build fails if home is not set
      bin/isabelle build -v -o system_heaps -b HOL
    '';
  
    installPhase = ''
      mkdir -p $out/bin
  