scalajs-snowpack-example VS tyrian

As for bundler: you don't have to use scalajs-bundler, since this is just an sbt plugin that can read JS configs from sbt and pass them to webpack. It is also quite old and buggy. Scala.js commands such as fastLinkJS or fullLinkJS produce plain old JS, so it's possible to use any existing bundler out there to bundle your SJS code with your JS dependencies. I had no clue about JS ecosystem when I was fiddling arounf with SJS, so I found the template that provides minimal setup for SJS + snowpack: https://github.com/lolgab/scalajs-snowpack-example.

If you want to try TEA, but not Elm I reccomend Scala.js with Tyrian[1]. Scala.js is a wonderful, mature project and Tyrian gives you the elm architecture in a very pragmatic way.

[1]: https://tyrian.indigoengine.io/

Have you looked at Laminar and Tyrian? Especially Tyrian seems to be close to what you're looking for.

What I wrote is obviously based on my experience as backend and data engineer. I'm so happy to see an adoption on the Frontend side (with things like Tyrian or OutWatch) and would be even happier if there was a clean path to Android. Out of curiosity, what do you find appealing in Scala, compared to e.g. Kotlin?

Documentation can be found at https://indigoengine.io/ and https://tyrian.indigoengine.io/.

Yes, I have. It didn't work out. There are quite neat libs like Tyrian, but they lack any ecosystem and I struggled to integrate it with pure JS libs - yet our app has a lot of very common components/widgets that we're really hesitating to write ourselves.