Shameless self-promotion: There's also https://hover.build, which builds a Go binary that runs the flutter engine to run your app. Can be used to easily deploy a Flutter app on desktop, and allows for cross platform plugins written in Go. It works, but is in early release. It is based on https://github.com/go-flutter-desktop/go-flutter
I tried this a couple of weeks ago, and to my surprise, it actually delivered! Except that the resulting apps didn't render quite correctly yet, so in the end I couldn't justify using it, yet.
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Hover probably suits my needs, but I think the Flutter engine could be separate from the app, on the desktop, as the Dart jitted VM seems to have enough performance to do so. That could fully remove the need for a toolchain for the majority of apps. Just feed it Dart, in source form.
In the case of Go, a library could enable communication with such a Flutter VM through channels. The resulting executable could be much simpler, and would merely focus on extending the VM with platform features. Concretely, it shouldn't be necessary to recompile the Flutter engine, just to add serial port access, for example. Likewise, the Flutter engine could be upgraded by simply replacing the binary.
The thing is, your language of choice, any, could be used to extend such an engine. Fundamentally I don't believe in monolithic apps which compile in the kitchen sink, as they don't allow me to use the best language for the task. Most languages try to be everything to everybody. Why not communicate better, between processes? Some of these processes may run on the other side of the world. That kind of stuff should be easy, so no DLL's please, instead a kind of broker.
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