Self types are a really interesting way to enforce type constraints in Scala. Learn to use it in a few minutes.
Learn to use Akka HTTP with Scala and send HTTP requests in just a few minutes with the Akka HTTP server DSL.
The Scala type system is powerful, but also hard. We look at contravariance in Scala and try to make some sense out of it.
Pattern matching is one of the most powerful Scala features. Learn to use it to the max so you can write your best Scala code.