The only things which they didn't solve is the hard GC pauses when developing really big projects or Scala. Mostly this happens on IntelliJ quite often if you are doing some work pauses while keeping IntelliJ open.

This happens quite often on bad machines and nearly never on machines with a really good memory module / awesome ssd's.

Still isn't easy to fix since they are working really hard to ensure performance on a lot of machines. Also that they support everything down to Java6 makes their codebase on some edges quite wierd.

Also I don't get it why they use so many languages at once (Java, Kotlin, Groovy) and I think some parts are in C++ (fileWatcher, launcher, restarter, updater, fsnotifier)?

(see: https://github.com/JetBrains/intellij-community)

>Also I don't get it why they use so many languages at once (Java, Kotlin, Groovy) and I think some parts are in C++ They seem to be mainly a Java shop. They probably use C++ for some performance intensive tasks where it makes a difference. Since they are creating Kotlin, they are starting to use it for their codebase as well.

Their different IDEs seem to be built on the same java core, but with extensions in the target language : Python for PyCharm, c# for ReSharper, ....

> why they use so many languages at once (Java, Kotlin, Groovy)

Kotlin is a JetBrains project. They're in the process of introducing Kotlin as a primary language for developing JetBrains applications, and Kotlin is still pre-1.0 release. As for Groovy, I think they want to replace it all with Kotlin code.

I've looked at Kotlin and I liked the design, too. I was just wondering why so many at once. But it would be great if they will replace Groovy at all.

Still I think it's too early to support Kotlin at Enterprise Level. Also I'm in the transition to FP (Functional Programming) and I think Kotlin still misses some functionality around that.

Edit: maybe I will use Kotlin to replace our JavaScript Stack (currently in Angular, but totally against any practice)