Re:Urn: A Lisp implementation for Lua
by UncleEntity on Monday March 12, 2018 @01:00PM
(#16569527)
Minischeme (can be found on github and elsewhere) could go on your list.
I found a copy of the original public-domain code a while back and have been hacking on it here and there, mostly pulling in fixes from tinyscheme.
I collect single-file language implementations. None in my collection (so far) use Lua, but I'm always on the lookout.