gui: i'm not talking about the GTK code here 'cause it should be compatible, but some other code in the gui was only designed for linux
some libs are also only crafted for linux, don't forget to find equivalent packages for xlib & any other linux only packages, on windows the Windows API python package should do the trick, but i have no idea about MAC OS
may also need to check threads (even if the most of threads use functions from libs)
This is a reminder for MAC OS support lack. To help you'll find below a list of things that may need or not to be changed.
Things already supported on MAC:
Things that absolutely need to be changed:
xlib
& any other linux only packages, on windows theWindows API
python package should do the trick, but i have no idea about MAC OS