Margarita Bobova
09/23/2026, 1:27 PMconst val initializers
• ⚙️ Compiler: cross-module inlining for KLIBs and a new warning when running the compiler on JDK versions older than 17
• 🌐 Kotlin/JS: a new ES2020 target and improved TypeScript export, including `unknown` for `dynamic` and `Any`
• 🕸️ Kotlin/Wasm: a new Playwright-based browser test DSL, smaller coroutine output, and companion blocks and extensions
• 🍏 Kotlin/Native: cross-language subtyping in Swift Export, KDoc export to Swift, and improved Swift Export support for cinterop protocols
• 🛠️ Server-side tooling: KAPT now generates Java sources directly instead of using `JCTree`, alongside Lombok and Java interoperability improvements
⚠️ Migration notes:
• The minimum supported Gradle version is now Gradle 8.14, and projects can no longer use multiple KGP versions
• Kotlin/Wasm no longer provides `wasmExports` in generated JavaScript files
• Kotlin/Native removes watchosArm32 and reports Apple x86_64 target deprecations as errors
💬 Give the preview a try! We’d be incredibly happy to hear about migration issues, unexpected behavior, or any other feedback reported in kotl.in/issue or here in Slack!