Flutter Built-in Kotlin Migration Required

[Hackermanteamofficial]

When building a Flutter project with recent Android Gradle Plugin (AGP 9.0+) and Flutter versions that support Built-in Kotlin, this plugin still applies the deprecated Kotlin Gradle Plugin ("org.jetbrains.kotlin.android").

During the build process, Flutter reports the following warning:

WARNING: Your app uses the following plugins that apply Kotlin Gradle Plugin (KGP): flutter_localization

Future versions of Flutter will fail to build if your app uses plugins that apply KGP.

Please migrate your plugin to Built-in Kotlin.

Additional warnings include:

Deprecated 'org.jetbrains.kotlin.android' plugin usage

The 'org.jetbrains.kotlin.android' plugin is no longer required for Kotlin support since AGP 9.0.

Expected Behavior

The plugin should be migrated to Android Gradle Plugin's Built-in Kotlin support and no longer apply:

org.jetbrains.kotlin.android

This will ensure compatibility with current and future Flutter and AGP releases.

Environment

• Flutter: Latest stable version
• Android Gradle Plugin (AGP): 9.0+
• Gradle: Latest supported version
• Kotlin: Built-in Kotlin enabled by Flutter migration
• Platform: Android

Impact

The plugin currently builds successfully, but Flutter warns that future versions may fail to build if plugins continue applying the Kotlin Gradle Plugin manually.

References

• https://docs.flutter.dev/release/breaking-changes/migrate-to-built-in-kotlin/for-plugin-authors
• https://kotl.in/gradle/agp-built-in-kotlin

Thank you for maintaining this package.

[channdara]

Thanks for opening the issue @Hackermanteamofficial

I'm working on migrating the Android KGP as soon as possible.

[channdara]

Hi @Hackermanteamofficial, just a small update here.

I have already migrated on my side but since this package depend on shared_preferences_android which is not yet migrating the Kotlin Gradle Plugin (KGP), I will hold my deployment for now and waiting for shared_preferences_android to migrate their package too.

[Hackermanteamofficial]

Thanks for your efforts.