v2.1.0-Beta2
What's New
Kotlin 2.1.0-Beta2 delivers significant performance improvements across the Analysis API with caching and lazy resolution, adds Xcode 16 support for Apple developers, and introduces WebAssembly incremental compilation. The K2 compiler gains stability with numerous debugger and private member access fixes, while new features include Kotlin-to-Java direct actualization and Compose's PausableComposition. Breaking changes include dropping language versions 1.4-1.5 and enforcing stricter requirements for external functions in Kotlin/Native.
Highlights
- Xcode 16 support for Apple ecosystem with XCFramework fixes
- WebAssembly incremental compilation and improved array type conversions
- Analysis API performance improvements with caching and lazy resolution
- Kotlin-to-Java direct actualization for expect/actual declarations
- K2 compiler stability fixes for debugger and private member access
- Compose compiler PausableComposition feature and deep copy optimization
- JVM bytecode version 23 support and language version 1.4/1.5 removal
Breaking Changes
- Dropped support for Kotlin language versions 1.4 and 1.5
- KLIB unique names via CLI now forbidden, use metadata instead
- Kotlin/Native @Escapes annotation now required for all external functions
- Nothing type prohibited as catch parameter in exception handling
Deprecations
- appendln deprecated in favor of appendLine
- Kotlin/Native freezing API marked for deprecation to error
- Reified type parameter instantiation into intersection types deprecated
- SubclassOptInRequired no longer marked as ExperimentalSubclassOptIn
Recent Releases
All releases →
v2.3.20-RC
Feb 19, 2026
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v2.3.10
Feb 5, 2026
Release Notes →
v2.3.10-RC2
Feb 2, 2026
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v2.3.20-Beta2
Jan 29, 2026
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v2.3.10-RC
Jan 19, 2026
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v2.3.20-Beta1
Jan 8, 2026
Release Notes →
v2.3.0
Dec 16, 2025
Release Notes →
v2.3.0-RC3
Dec 9, 2025
Release Notes →
v2.3.0-RC2
Dec 2, 2025
Release Notes →
v2.3.0-RC
Nov 18, 2025
Release Notes →
v2.3.0-Beta2
Oct 28, 2025
Release Notes →