LuaJIT is not the standard mainline Lua interpreter that most people think of as "Lua the language". It's still a fairly young, experimental project and you wou

LuaJIT is not the standard mainline Lua interpreter that most people think of as "Lua the language". It's still a fairly young, experimental project and you wouldn't want to write production code in it. However, the standard Lua distribution is still much faster than Ruby. But even though both are dynamic interpreted languages, it's still apples to oranges - they have very different design goals. Still, I think it's a copout to say performance doesn't matter in any general-purpose language the way the core Ruby team seems to. Micro-optimization is a waste of time, but efficiency and intelligent implementation choices are necessary.