Quite some apps are made with React Native these days. Expo is an app that allows developing and running apps build with React Native more easily. I'd love to see this available on F-Droid, and wonder if more people would be interested.
It is open source (BSD + 3rd party MIT, Apache, CC, etc.), but does integrate with play services, crashlytics, its own API (but app works without using it), and perhaps more. May need several android SDK versions to build, also requires the android NDK.
What would be the way to go about this? Try to find support with the app itself and introduce feature toggles for proprietary services; and if that fails, maintain a fork?
It looks like it would be quite a job, but as it paves the way for more React Native and Expo apps to appear within F-Droid, perhaps it is actually worth it.