Pretty interesting. I'm a professional user of Lua, and while I love it, I really get frustrated at a lot of aspects of it, especially how loose the typing is. I've long wished there were more strongly typed alternatives, but just nothing compares to the performance, stability, and quality of documentation of Lua. I'm not sure how I would embed this in a non-Zig project, though.
Curious, if you don't mind, what kind of professional usage with Lua you work on? I was working on some Nginx/Openresty scripting with Lua module to implement kind of web edge service and really liked it.
Much of the functionally has been wrapped or customized to disallow any system access that doesn't go through an access control layer, including for require, and disallowing catching certain errors with pcall and through coroutines. Anything that could feasibly break the sandbox is also removed, like the debug package, and the ability to load bytecode (text sources only). The actual Lua sources are 100% vanilla, though we complete it with C++ to be compatible with the rest of the codebase.