FYI, for those who may not be aware, moonscript is the "coffeescript" for lua. It has been in production use for quite a while (the author of moonscript also created itch.io, using ... moonscript).

yuescript, from the dora-ssr game engine dev, is essentially moonscript-2.0

And of course, if you want to treat lua as the scheme-like it really is (deep down), then ... fennel.

Lots of choices. They all compile to straightforward lua, are very easy to incorporate (you can even compile at runtime, if you wish), and all employ full lua semantics, meaning zero runtime overhead

EDIT: and the curse of not reading fully ahead strikes again (doh!). Someone else has made the same points below ...