# Kotlin v2.3.21-RC released!

**URL:** <https://forum.devtalk.com/t/kotlin-v2-3-21-rc-released/240389>\
**Category:** Backend Official News\
**Tags:** newsbot, official-news, kotlin\
**Created:** [7 April 2026 15:24 UTC](https://forum.devtalk.com/t/kotlin-v2-3-21-rc-released/240389 "2026-04-07T15:24:44Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![NewsBot](https://forum.devtalk.com/user_avatar/forum.devtalk.com/newsbot/32/1114_2.png) [@NewsBot](https://forum.devtalk.com/u/NewsBot)\
**Post date:** [7 April 2026 15:24 UTC](https://forum.devtalk.com/t/kotlin-v2-3-21-rc-released/240389/1 "2026-04-07T15:24:45Z")

</div>

[Kotlin](https://devtalk.com/kotlin) v2.3.21-RC has been released.

> [@](#):
>
> ## Changelog
> 
> ### Backend. Wasm
> 
> - [`KT-84610`](https://youtrack.jetbrains.com/issue/KT-84610) [Wasm] Failed to compile klibs in IC mode
> 
> ### Compiler
> 
> - [`KT-84678`](https://youtrack.jetbrains.com/issue/KT-84678) K/N: Undefined symbol from SPM-added ObjC frameworks when linking iOS target
> - [`KT-84566`](https://youtrack.jetbrains.com/issue/KT-84566) Prevent launching Default dispatcher threads from IJ SDK in kotlin compiler
> - [`KT-85021`](https://youtrack.jetbrains.com/issue/KT-85021) False positive SUBCLASS\_CANT\_CALL\_COMPANION\_PROTECTED\_NON\_STATIC error in multi-module project
> 
> ### JavaScript
> 
> - [`KT-82395`](https://youtrack.jetbrains.com/issue/KT-82395) Support top-level declarations from compiler plugins in JS incremental compilation
> - [`KT-84633`](https://youtrack.jetbrains.com/issue/KT-84633) Kotlin/JS: “Serializer for class not found” error when IR output granularity is `whole-program`
> - [`KT-85047`](https://youtrack.jetbrains.com/issue/KT-85047) Kotlin/JS: `@JsStatic` on suspend fun of class companion generates incorrect d.ts
> - [`KT-84517`](https://youtrack.jetbrains.com/issue/KT-84517) K/JS: bad mappings data in outputted Kotlin stdlib source map
> 
> ### Libraries
> 
> - [`KT-71848`](https://youtrack.jetbrains.com/issue/KT-71848) Kotlinx.metadata: Add `CompilerPluginData` into Km API
> 
> ### Tools. Gradle
> 
> - [`KT-84729`](https://youtrack.jetbrains.com/issue/KT-84729) Update Gradle plugin-publish version to enable configuration cache badge on Gradle plugins portal
> 
> ### Tools. Gradle. Compiler plugins
> 
> - [`KT-85257`](https://youtrack.jetbrains.com/issue/KT-85257) AGP/Compose: MergeMappingFileTask clears R8 artifacts due to `@OutputDirectory` annotation on AGP 9.1+
> 
> ### Tools. Scripts
> 
> - [`KT-84842`](https://youtrack.jetbrains.com/issue/KT-84842) scriptCompilationClasspathFromContext behavior changed from 2.3.10 to 2.3.20
> - [`KT-85029`](https://youtrack.jetbrains.com/issue/KT-85029) Kotlin Scripting: ScriptDiagnostic reports “at null” instead of error locati…

Link: [Release Kotlin 2.3.21-RC · JetBrains/kotlin · GitHub](https://github.com/JetBrains/kotlin/releases/tag/v2.3.21-RC)