I've used Scala mainly for Apache Spark applications and do enjoy it. Pros: * The type system * Being able to mix functional and OO design coherently

I've used Scala mainly for Apache Spark applications and do enjoy it. Pros: * The type system * Being able to mix functional and OO design coherently * Less verbose than Java * Utilise existing Java libraries Cons: * Huge amount of syntax to learn * Fragile and slow package managers * sbt uses Ivy and so downloads package files in a single thread. In Australia this is horrible * too slow for scripting due to JVM boot time