[darzu]

Roblox uses a heavily customized version of Lua, and in it they've fixed many of the pain points of Lua and JS. One example is their Lua allows value types/copy semantics, native number types like f32 / i32, and simd. These are important if you care about tracking performance carefully which I believe they do.

They use Lua heavily in Roblox so they've got a lot of tools and expertise in it, so I assume they see a lot of benefit to further standardizing their high level language.

I'm guessing they have some tooling to auto-translate typescript into Lua to massively speed up their porting. TypeScript has a very good compiler API for doing exactly this sort of thing and I've written a decent TypeScript <-> Python translation before.

[dehrmann]

This scares me. Lua is already pretty niche, they customized it, and it's getting transpiled to js or wasm. There are too many places for that to go wrong, problems will be hard to investigate, and it's added ramp-up time for new hires.

In general, any time you venture away from a platform's default language (Objective C, Swift, Java, Kotlin, JS), things get significantly more complicated.

[mid-kid]

If there's any language where that ramp-up time might not even be a problem, it's Lua.