Super cool and demo compat is a big achievement here!

I do feel a little, idk iffy about the MIT license. It's pretty clearly not a clean room reimplementation, and routing around the GPL like this feels not totally cool. I definitely think it's legal, but idk, when id was cool enough to open source their code under the GPL and you route around it like this, feels against the spirit and maybe disinclines other companies to do similar things... though probably no one cares tbh.