I should have mentioned that "async coroutines" (i.e., goroutines) are also a requirement. Also, I understand that Lua doesn't have much of a standard library and isn't really used as a general purpose programming language (compared to Python, for example)?

Your understanding is correct, it's an embedded-first language. It also makes it very hackable which means that I fully believe golang-like goroutines would be achievable in Lua.

People hack the `continue` statement into it all the time, it wouldn't be terribly surprising.