Kotlin 2.1.20 Released

The Kotlin 2.1.20 release is out! This version includes performance improvements and bug fixes for Kotlin 2.1.0. Here are some highlights from this release:

• K2 compiler updates: New default kapt compiler plugin.
• Kotlin Multiplatform: A new DSL to replace Gradle’s Application plugin in multiplatform projects.
• Kotlin/Native: Inlining optimization to improve runtime performance.
• Kotlin/Wasm: Custom formatters are now enabled by default in development builds.
• Gradle support: Support for adding custom publication variants in multiplatform and JVM projects.
• Standard library: Introduction of common atomic types, improved UUID support, and a new time-tracking functionality.
• Compose compiler: Now includes source information by default across all platforms.

For the complete list of changes, refer to What’s new in Kotlin 2.1.20 or the release notes on GitHub.

How to install Kotlin 2.1.20

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.

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

If you need the command-line compiler, download it from the GitHub release page.

If you run into any problems

• Find help on Slack (get an invite).

• Report issues to our issue tracker, YouTrack.

Special thanks to our EAP Champions

• Zac Sweers
• Alexander Nozik
• Benoit ‘BoD’ Lubek
• Yang
• Jake Wharton
• Rick Clephas
• Russell Wolf
• Johannes Svensson
• Łukasz Wasylkowski
• David Lopez
• Artyom Shendrik
• Florian Schreiber
• Sechaba Mofokeng
• Amr Yousef
• Kacper Wojciechowski
• Bernd Prünster
• Anderson Lameck

What else to read

• What’s new in Kotlin 2.1.20 documentation
• Kotlin 2.1.0 compatibility guide
• K2 compiler migration guide
• K2 Compiler Performance Benchmarks and How to Measure Them on Your Projects
• Kotlin EAP Champions