We did have a project some years ago looking at extending LuaJIT on which Tom Fransham did excellent work. Alas, the funder's priorities moved on (as is their right!), so we didn't get to finish it. It was a bit sad, as we (well, mostly Tom) had built up a real head of steam, but c'est la vie. Still, either way, I would never have claimed enough personal expertise with LuaJIT to take over maintainership!
He left for a break, returned and there was no second break or anything.
I don't want to spam it in repo, so leaving it here: he is kind of a hero doing this work and I (hopefully we) am very grateful for his contribution to this world.