v2.0.20-RC2
What's New
Kotlin v2.0.20-RC2 addresses critical stability issues across K2 compiler, native platforms, and JavaScript targets. Key fixes include NPE crashes, watchOS runtime failures, and performance degradation in generic type handling. The Compose compiler update enforces stricter binary compatibility rules for @Composable functions.
Highlights
- Fixed critical NPE in backend when using DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE
- Resolved K2 compiler crashes with type arguments and lambda returns
- Fixed EXC_BAD_ACCESS crashes on watchOS with Dispatchers and Random
- Improved K2 compilation performance for mutually recursive generic bounds
- Enhanced Compose compiler binary compatibility by restricting open @Composable functions
- Fixed JavaScript HTTP client errors when targeting ES2015 with KTOR
Breaking Changes
- Compose compiler now disallows open @Composable functions with default parameters
Recent Releases
All releases →
v2.3.20-RC
Feb 19, 2026
Release Notes →
v2.3.10
Feb 5, 2026
Release Notes →
v2.3.10-RC2
Feb 2, 2026
Release Notes →
v2.3.20-Beta2
Jan 29, 2026
Release Notes →
v2.3.10-RC
Jan 19, 2026
Release Notes →
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 →