We do something similar for the UI for our audio hardware product. AES70 control messages are sent over Flutter platform channels to a Swift backend. The glue is open source - GitHub.com/PADL/FlutterSwift.

This is very cool! I'm going to take a look at your code.

I've been playing with the idea of creating a "protobuf db" library that would allow you define schemas in protobuf and then query them with something akin to an ORM. It wouldn't make any sense for large databases, but for embedded applications that only need to store a few MB of data, it would be perfect.