@M16 cubescript is usually client side. All the server programming is done in C++ and Lua. You can see the map battle code here: https://github.com/illogica/Pastaland/blob/master/scripts/std/mapbattle_gst.lua (credit goes to @DipShitStar for the map battle code) while the whole mod source code is here: https://github.com/pisto/spaghettimod
Pastaland is basically an add-on over spaghettimod, and everything is open source. Code contributions are welcome, and don't be surprised if the devs won't implement your ideas for you: grab the code and start hacking.