[gorohoroh]

Frontend is in Java (and Kotlin), indeed, as it's a part of the IntelliJ platform. However, the backend that actually provides IDE features for C# is written in .NET. The backend is actually the same ReSharper logic that runs in Visual Studio but in headless mode.

[winterbe]

Wondering how much code in Intellij Ultimate is already written in Kotlin. Parts of Kotlin Code in Intellij Community Edition is still kinda low:

https://github.com/JetBrains/intellij-community/search?l=kot...