If you haven't ever used Forth or made a Forth interpreter, it's a fun project that I recommend doing.
It would be nice to see it run under Linux... the C source looks too much like typical "be as clever as possible" macro magic, which my non-C adjusted brain can't hack.
I'll re-implement in either assembler, or free pascal.
The reason is that STOICAL implements types, arrays, and dictionaries in what seems to be a quite reasonable and sane matter.
It does type checking when you want, and seems like it could do object oriented as well, if I can push it that way.
My greatest motivation to learn Forth inside and out is its value in rebuilding civilization if we ever find ourselves in a place where a significant amount of technology has been lost. I don't think there's a more powerful and yet incredibly simple way to bootstrap a general purpose programming environment than writing a Forth. It's a relatively small amount of knowledge that needs to be preserved, compared to all the complexity that would be needed to have compilers, garbage collectors, and all that jazz again.
I mean, that's just my personal take on it.
I have seen embedded Forth developers do this on new CPUs and its fast and potent.