To answer my own questions, yes it uses (relies on) LuaJIT and there seems to be no problem running multiple Lua states, each using Terra. In fact because of the independent nature of compiled Terra code, I would wager you can create the Lua states with Terra and threads from within Terra itself. LuaJIT actually can't do this currently, you need a little bit of C code, because the callback passed to pthread_create will be invoked in a new thread on the old state (which would be invalid in LuaJIT as you can't share a state across threads like that.) Anyway I'll try it out and submit it as a test case for Terra if it works.
