v2.3.20 Developer Guide
What's New for Developers
Kotlin 2.3.20 delivers significant improvements to collection literals, Analysis API capabilities, and Wasm compilation efficiency. The release focuses on stability with extensive bug fixes across FIR analysis, explicit backing fields, and JVM interoperability, while introducing enhanced contract support and better Java annotation handling for improved type inference.
Highlights
- Collection literals inference implementation with support for standard library factory functions
- Enhanced Analysis API with KDoc extraction, functional type creation, and annotated type support
- Wasm backend improvements: single module mode support, Safari load time fixes, JS String integration
- Contract support expanded to property accessors and context parameters
- Explicit backing fields stability improvements and visibility fixes
- JVM bridge generation for abstract interface methods improving binary compatibility
Breaking Changes
- K1 API deprecation level changed from Warning to Error
- Context receivers resolution removed in K2 mode
- KaFunctionType.arity deprecated in favor of parameter count API
Deprecations
- KaSymbolInformationProvider getter and setter deprecation status methods
- Multiple Analysis API classes renamed with Ka prefix for consistency
- KaType.enhancedType name too general, renamed to enhancedNullability
Recent Releases
All releases →
v2.3.20
Mar 16, 2026
Release Notes →
v2.3.20-RC3
Mar 10, 2026
Release Notes →
v2.3.20-RC2
Mar 3, 2026
Release Notes →
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 →