For many libraries, it's pretty easy to write code that works across all the versions. For many differences it's not too difficult to implement code for maximum

For many libraries, it's pretty easy to write code that works across all the versions. For many differences it's not too difficult to implement code for maximum compatibility: http://leafo.net/guides/setfenv-in-lua52-and-above.html http://leafo.net/guides/setfenv-in-lua52-and-above.html For me personally, the advantages of luajit currently outweigh the desire to upgrade to newer versions of the language. Regarding Lua 5.1 being old, I haven't really found it to be an issue.. Lua isn't like most scripting languages, it doesn't come with a huge standard library. It's effectively just the language and some primitives. So it ages quite well as is.