If you really need to use LuaJIT, then you best stick with Lua 5.1. Otherwise, use Lua 5.3---it supports 64-bit integers (unlike Lua 5.1/5.2, which only use fl

If you really need to use LuaJIT, then you best stick with Lua 5.1. Otherwise, use Lua 5.3---it supports 64-bit integers (unlike Lua 5.1/5.2, which only use floating point) and if you are doing any parsing of binary data, string.pack() and string.unpack() are worth using (Lua 5.3). Yes, there are issues with some Lua modules not supporting Lua 5.3, but the major modules support it, and LuaRocks makes installing modules rather easy.