Lua (and to a somewhat lesser extent Luau) are small in terms of the learned surface of the value language, not necessarily in terms of lines of code. That being said, any runtime use of the language needn't depend on Analysis, which is the biggest compilation unit by far.

Probably also worth mentioning that Analysis currently contains two full type system implementations because we've spent the better part of the past three years building a new type system to address a lot of the fundamental limitations and architectural issues that we'd run into after years of working on the original one. The new one is not without issues still, but is definitely very usable, and gets better and better every week. At some point in the future, we will clip the old one altogether, and that'll shave off some 30,000 lines of code or something.