I am currently working on a Lua 5.3 compatibility layer for ComputerCraft, and it would be really handy to have a 64 bit version bitwise operations API (or even an arbitrary bit size, to work with 128 bit or 256 bit values) for Lua 5.3 features like string.pack. Of course, string.pack and string.unpack is quite useful for converting data to and from binary before writing to files.