anchor.diff:  
     setupHook = ./setup-hook.sh;
   
  -  meta = with stdenv.lib; {
  +  meta = with lib; {
       description = "Open RTL synthesis framework and tools";
       homepage    = "http://www.clifford.at/yosys/";
       license     = licenses.isc;
  
positive.code:   };
  
    enableParallelBuilding = true;
    nativeBuildInputs = [ pkg-config ];
    buildInputs = [ tcl readline libffi python3 bison flex protobuf zlib ];
  
    makeFlags = [ "ENABLE_PROTOBUF=1" "PREFIX=${placeholder "out"}"];
  
    patchPhase = ''
      patch -p1 < ${./plugin-search-dirs.patch}
      substituteInPlace ./Makefile \
        --replace 'echo UNKNOWN' 'echo ${builtins.substring 0 10 src.rev}'
  
  
negative.code: { stdenv, lib
  , abc-verifier
  , bash
  , bison
  