Kotlin Multiplatform v2.3.20-Beta1 Release Notes & Developer Guide

Kotlin v2.3.20-Beta1 introduces Collection Literals inference, unnamed local variables, and expanded contract support for property accessors. WebAssembly gains single module compilation with TypeScript generation and improved performance through eliminated unnecessary conversions. The Analysis API receives significant enhancements including KDoc extraction, functional type builders, and context parameter support, while the compiler fixes numerous edge cases in type inference, generic handling, and interoperability.

Highlights

• Collection Literals inference support for improved type safety and cleaner syntax
• Unnamed local variables feature reduces boilerplate in destructuring and loops
• WebAssembly single module mode with TypeScript generation and debugger support
• Analysis API enhancements: KDoc extraction, functional type creation, context parameters
• Wasm performance improvements eliminating unnecessary Any-JsAny conversions
• Contract support for property accessors and context parameters