anchor.diff:  , useBoehmgc ? true, boehmgc
   }:
   
  -assert useBoehmgc -> boehmgc != null;
  -
   let
     s = # Generated upstream information
     rec {
       baseName="ecl";
       version="16.1.2";
       name="${baseName}-${version}";
  -    url="https://common-lisp.net/project/ecl/static/files/release/ecl-16.1.2.tgz";
  +    url="https://common-lisp.net/project/ecl/static/files/release/ecl-${version}.tgz";
       sha256="16ab8qs3awvdxy8xs8jy82v8r04x4wr70l9l2j45vgag18d2nj1d";
     };
     buildInputs = [
  
positive.code:     "--with-gmp-libdir=${lib.getLib gmp}/lib"
      # -incdir, -libdir doesn't seem to be supported for libffi
      "--with-libffi-prefix=${lib.getDev libffi}"
      ]
      ++
      (lib.optional (! noUnicode)
        "--enable-unicode")
      ;
  
    patches = [
  
negative.code:       --prefix NIX_LDFLAGS_BEFORE_${gcc.bintools.suffixSalt} ' ' "-L${lib.getLib libffi}/lib"
    '';
  
    meta = with lib; {
      inherit (s) version;
      description = "Lisp implementation aiming to be small, fast and easy to embed";
      license = licenses.mit ;
      maintainers = [ maintainers.raskin ];
      platforms = platforms.unix;
    };
  }
  