sbt-crossproject VS Converter

SBT. It's not because of the pseudo-scala config language, that looks especially alien next to braceless Scala 3 code. Or the weird symbolic operators. The big problem is correctness; in almost every project I've had to use spray-resolver because I've encountered weird bugs because SBT reuses the same dirty JVM. I really thing Drip would help here. I'll keep using SBT because it has the best Scala ecosystem support and great plugins like sbt-crossproject. It would also be great to be able to write build.sbt files in modern, regular Scala.

The longer story is that st-material-ui incorporates https://github.com/ScalablyTyped/Converter/pull/487 in order to get much, much cleaner API. You'll probably have seen the fake literal types, some rewriting from type unions to inheritance, things like that.

Given that you want interoperability with js, I'd start by playing with https://scalablytyped.org/, then, play with the scalajs-react demos (https://github.com/ScalablyTyped/ScalaJsReactDemos) and the slinky demos (https://github.com/ScalablyTyped/SlinkyDemos). There are some libraries that scalablytyped doesn't support pretty well but you can leverage https://github.com/nafg/scalajs-facades for those.

ScalaJS is awesome. Really solid and mature project, can totally recommend.

The only thing that can be annoying is when you want to have a typesafe interface and have to write a lot of adapters for javascript libraries.

Fortunately there is even a project that can make use of typescript interfaces for those libraries, so that you can use them from ScalaJS more or less automatically: https://scalablytyped.org/

I'm using it mostly for full-stack web development with ScalaJS (https://www.scala-js.org) in the frontend (https://outwatch.github.io/docs/readme.html) and in the backend with AWS lambdas.

The ecosystem is currently in the process of porting all the libraries to Scala 3. So if you're new to Scala, I'd recommend to start with Scala 2, which is rock-solid and already very powerful.

I never worked with SQLAlchemy. But on the scala database side, popular libraries are Doobie (https://tpolecat.github.io/doobie) and Quill (https://getquill.io). Keep in mind that these are for Scala on the JVM. On the ScalaJS side I'm using the javascript library pg. But I'd like to try if it works well with Prisma soon.

The nice thing about ScalaJS is, that you can use Javascript libraries. And if there are typescript facades, then you can transpile these to Scala and use them in a type safe way (https://scalablytyped.org).