If you need other platforms, here is the link. Don't download 64-bit version, the compiled code is not compatible.
Then all you have to do is typing command as following
luac5.1 -s -o filename.luac filename.lua
To protect your scripts further, you can encrypt luac files to luae2 files with AnkuLua. First, select the luac script to encrypt. Then click the upper right three dots and "Encrypt Scripts". The encrypted luae file will be in the same directory.
"You could use loadstring to get a chunk then string.dump and then apply some transformations like cycling the bytes, swapping segments, etc. Transformations must be reversible. Then save to a file.
Note that anyone having access to your "encryptor" Lua module will know how to decrypt your file. If you make your encrypted module in C/C++, anyone with access to source will too, or to binary of Lua encryption module they could require the module too and unofuscate the code. With interpreted language it is quite difficult to do: you can raise the bar a bit via the above the techniques but raising it to require a significant amount of work (the onlybreal deterent) is very difficult AFAIK."