Just in case anyone else was wondering, it seems that some early products (running AirOS) were modified versions of OpenWRT, but later software/hardware is not.

So yes, this comment is correct, but it threw me since I wasn’t following the company back then and I hadn’t heard of that history before.

Pretty sure the unifi firmware on APs is still modified openwrt as are many of their other products.

Just look for syswrapper.sh

(Very long time ubiquiti user, alpha tester, etc)