Implementing a Sticky Service in android/flutter

I need to add a native sticky background service in a flutter application, in order to achieve 2 things:

1. Starting at boot time and running in background indefinitely
2. Exchange data with the main Dart activity, in a message passing fashion

However, I cannot find any kind of useful documentation. It seems that for now, you have to choose to go completely native or giving up using low level features and focus only on the UI (until someone pulls a specific plugin out of the hat).

Thus, my question is the following: what is the easiest way to achieve this sort of integration, starting with a basic flutter project ?

Thank you

from Implementing a Sticky Service in android/flutter