Add javascript API using CDN

New wix code functionality is awesome, however, it would be very useful if I could have access to use other API/libaries as well. I know wix already uses cdn so it would be good if I could have a way to add to this list of imported modules.

example usage: I am building a game website. I want to use my backend: ( playfab ) to populate some data like a leaderboard on my page. However, right now I could not find a good way to include there API.