JetBrains has released Kotlin 2.0.20, bringing significant performance improvements, including concurrent marking for the garbage collector (GC) that should shorten GC pause times and enhance application responsiveness. This update follows Kotlin 2.0.0 and also includes bug fixes, support for Gradle versions 8.6 to 8.8, and improvements in Kotlin Multiplatform development.

Additionally, Kotlin 2.0.20 begins migrating the visibility of the data class .copy() function to align with the constructor's visibility in future releases. The Kotlin plugins supporting this version are bundled with the latest IntelliJ Idea and Android Studio IDEs, eliminating the need for developers to update their plugins.