[calamari4065]

FCC certification is for the entire system, firmware included.

The reason the modules with integrated antenna are so popular is that the module carries its own certification, so you don't need to do it yourself.

If you use the module with an antenna connector instead of integrated, you must get your own FCC certification. It's for the entire system.

> Why can't one have an open source stack with specific builds that are approved, tested and certified?

Mainly because it's heinously expensive and difficult.