What does Insurgence use for wifi battling?

Some of my friends and I are working on a thing and we wanted to implement wifi battles, so I’m wondering what they use and how it works.

There is https://battling.p-insurgence.com, because I can’t remember if in-game battling works yet. You can use the export option in your pokemon menu (like when you click the pokemon to see the summary or switch) to get the pokemon files that you can import into the simulator.

You mean our trading software?

The server side can be found here: https://github.com/Deukhoofd/InsurgenceServer