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Android Gradle Plugin 9 applies Kotlin itself and fails if you also apply the Kotlin plugin

added 2026-09-02·view source

androidgradlekotlin

Fact

From AGP 9.0 the Android plugin has built-in Kotlin support. Applying org.jetbrains.kotlin.android next to it is not merely redundant — the build fails outright with "The 'org.jetbrains.kotlin.android' plugin is no longer required for Kotlin support since AGP 9.0".

The Compose compiler plugin is a separate concern and is still applied by hand.

Why it matters

Every Android/Kotlin project written before AGP 9 declares that plugin, and every tutorial still shows it. The failure lands at plugin-application time, before any of your code is compiled, so it looks like a broken toolchain rather than a two-line config change.

How to apply

When moving to AGP 9, drop org.jetbrains.kotlin.android from the module and from the root plugins {} block, and keep org.jetbrains.kotlin.plugin.compose if the project uses Compose. Set the JVM target through the kotlin extension rather than the removed android.kotlinOptions:

kotlin {
    compilerOptions {
        jvmTarget = JvmTarget.JVM_17
    }
}

Recent AndroidX releases pull the other way: they require AGP 9.1+ and a compileSdk newer than AGP 8 will accept, so the upgrade is usually forced by a dependency bump rather than chosen.

Sources