What's new in Kotlin 2.1.20-Beta1

IDE support

The Kotlin plugins that support 2.1.20-Beta1 are bundled in the latest IntelliJ IDEA and Android Studio. You don't need to update the Kotlin plugin in your IDE. All you need to do is to change the Kotlin version to 2.1.20-Beta1 in your build scripts.

See Update to a new release for details.

Kotlin K2 compiler: new default kapt plugin

Starting with Kotlin 2.1.20-Beta1, the K2 implementation of the kapt compiler plugin is enabled by default for all the projects.

The JetBrains team has launched the new implementation of the kapt plugin with the K2 compiler back in Kotlin 1.9.20. Since then, we have further developed K2 kapt's internal implementation and made its behavior similar to that of K1 kapt, while significantly improving its performance.

If you encounter any issues when using kapt with the K2 compiler, you can temporarily revert to the previous kapt plugin implementation.

To do this, add the following option to the gradle.properties file of your project:

Please report such issues to our issue tracker.

Gradle: support for version 8.11

Kotlin 2.1.20-Beta1 is now compatible with the latest stable Gradle version, 8.11, and supports its features. Gradle versions 8.7 to 8.11 are supported, with one exception. If you use the Kotlin Multiplatform Gradle plugin, you may see deprecation warnings in your multiplatform projects when calling the withJava() function in the JVM target. We plan to fix this issue as soon as possible.

For more information, see the related issue in YouTrack.

How to update to Kotlin 2.1.20-Beta1

Starting from IntelliJ IDEA 2023.3 and Android Studio Iguana (2023.2.1) Canary 15, the Kotlin plugin is distributed as a bundled plugin included in your IDE. This means that you can't install the plugin from JetBrains Marketplace anymore. The bundled plugin supports upcoming Kotlin EAP releases.

To update to the new Kotlin EAP version, change the Kotlin version to 2.1.20-Beta1 in your build scripts.