# LuaJIT

51 Hacker News commenters recommended LuaJIT and 18 criticized it, November 2025 to November 2026. It was recommended in 12 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** Fast Lua 5.1 implementation with a JIT and easy C FFI, used in production for years. Critics say it is stuck on 5.1 and not fully PUC Lua compatible.

## Why people recommend it

- Very fast, near C performance (5 comments): "LuaJIT is best in class performance for a scripting language -by a huge margin." ([source](https://news.ycombinator.com/item?id=46379687)) "handles double, strings, and dictionaries at near C level performance" ([source](https://news.ycombinator.com/item?id=50281950)) "LuaJIT is still more performant and more widely used than PUC Lua" ([source](https://news.ycombinator.com/item?id=46379783))
- Easy C FFI integration (5 comments): "Fortunately love is built on LuaJIT, which does support integer math through the built-in ffi library." ([source](https://news.ycombinator.com/item?id=47821091)) "it's a lot easier to write an API layer in Lua with LuaJIT than it is to do from C" ([source](https://news.ycombinator.com/item?id=48680262)) "using luajit so that the lua runs very fast and has a super easy C FFI" ([source](https://news.ycombinator.com/item?id=47654808))
- Used in production for years (4 comments): "wrote entire stacks and apps on top in LuaJIT that I got paid for and are running without any problems after many years" ([source](https://news.ycombinator.com/item?id=50142697)) "LuaJIT is still more performant and more widely used than PUC Lua" ([source](https://news.ycombinator.com/item?id=46379783)) "Luajit is already popular and has plenty of benchmarks online." ([source](https://news.ycombinator.com/item?id=46035606))
- Small, simple language core (3 comments): "Keeps implementation much simpler and much faster, + it makes you be more careful how you are structuring and writing your code." ([source](https://news.ycombinator.com/item?id=49063071)) "I really liked the idea of the simplicity and size of Lua/luajit" ([source](https://news.ycombinator.com/item?id=48311014)) "LuaJIT is king because Lua is such a small language" ([source](https://news.ycombinator.com/item?id=47846383))

## What people warn about

- Diverges from PUC Lua (4 comments): "Seems like a bad idea to actively diverge from Lua, hostile even, especially without at least a clear change of name." ([source](https://news.ycombinator.com/item?id=48668723)) "Why not work together with the PUC Lua team to add some of these to both lua versions" ([source](https://news.ycombinator.com/item?id=48678972)) "I don't know why they are diverting from lua spec on other aspects though." ([source](https://news.ycombinator.com/item?id=48673729))
- Stuck on Lua 5.1 (3 comments): "From what I've heard it in practice isn't developed anymore and is stuck at Lua 5.1 still." ([source](https://news.ycombinator.com/item?id=46370364)) "So is LuaJIT resuming active development after a decade or so of only maintenance? Great!" ([source](https://news.ycombinator.com/item?id=48667563)) "LuaJIT has held back the lua ecosystem for over a decade" ([source](https://news.ycombinator.com/item?id=48672606))
- Syntax extensions add complexity (3 comments): "It will make everything more complicated as there are now two ways to do everything." ([source](https://news.ycombinator.com/item?id=48668579)) "I dislike basically everything about these syntax extensions." ([source](https://news.ycombinator.com/item?id=48669747)) "This stuff (especially the ternary) are a step backwards." ([source](https://news.ycombinator.com/item?id=48673815))

## Alternatives hackers recommend

- [Luvit](https://hackerapproved.com/p/luvit.md): 6 recommend
- [TurboLua](https://hackerapproved.com/p/turbolua.md): 5 recommend

## Cite as

Hacker Approved, "LuaJIT", https://hackerapproved.com/p/luajit/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).