devel-jb-kotlin-tooling-agp9-migration

--| | android.uniquePackageNames | false | true | Ensure each library has a unique namespace | | android.enableAppCompileTimeRClass | false | true | Refactor switch on R fields to if/else | | android.defaults.buildfeatures.resvalues | true | false | Enable resValues = true where needed | | android.defaults.buildfeatures.shaders | true | false | Enable shaders where needed | | android.r8.optimizedResourceShrinking | false | true | Review R8 keep rules | | android.r8.strictFullModeForKeepRules | false | true | Update keep rules to be explicit | | android.proguard.failOnMissingFiles | false | true | Remove invalid ProGuard file references | | android.r8.proguardAndroidTxt.disallowed | false | true | Use proguard-android-optimize.txt only | | android.r8.globalOptionsInConsumerRules.disallowed | false | true | Remove global options from library consumer rules | | android.sourceset.disallowProvider | false | true | Use Sources API on androidComponents | | android.sdk.defaultTargetSdkToCompileSdkIfUnset | false | true | Specify targetSdk explicitly | | android.onlyEnableUnitTestForTheTestedBuildType | false | true | Only if testing non-default build types |

Check for and remove properties that now cause errors:

• android.r8.integratedResourceShrinking — removed, always on
• android.enableNewResourceShrinker.preciseShrinking — removed, always on

Pure Android Tips

For non-KMP Android modules upgrading to AGP 9.0:

• Remove org.jetbrains.kotlin.android plugin — AGP 9.0 includes Kotlin support built-in (see "Built-in Kotlin Migration" above)
• Migrate kapt to KSP or com.android.legacy-kapt
• Migrate kotlinOptions to kotlin { compilerOptions {} }
• Migrate kotlin.sourceSets to android.sourceSets with .kotlin accessor
• Review new DSL interfaces — BaseExtension is removed; use CommonExtension or specific extension types
• Java default changed from Java 8 to Java 11 — ensure compileOptions reflects this
• R class is now compile-time non-final in app modules — refactor any switch statements on R class fields to if/else
• targetSdk defaults to compileSdk if not set — specify targetSdk explicitly to avoid surprises
• NDK default changed to r28c — specify ndkVersion explicitly if using native code
• Temporary opt-out: android.builtInKotlin=false + android.newDsl=false in gradle.properties (removed in AGP 10)

Verification

After migration, verify with the checklist. Key checks:

1. ./gradlew build succeeds with no errors
2. ./gradlew :androidApp:assembleDebug succeeds (if app module exists)
3. No com.android.library or com.android.application in KMP modules
4. No org.jetbrains.kotlin.android in AGP 9.0 modules
5. Source sets use correct names (androidMain, androidHostTest, androidDeviceTest)
6. No deprecation warnings about variant API
7. Run configurations point to correct modules

Common Issues

See references/KNOWN-ISSUES.md for details. Key gotchas:

KMP Library Plugin Issues

• BuildConfig unavailable in library modules — use DI/AppConfiguration interface, or use BuildKonfig or gradle-buildconfig-plugin for compile-time constants
• No build variants — single variant architecture; compile-time constants can use BuildKonfig/gradle-buildconfig-plugin flavors, but variant-specific dependencies/resources/signing must move to app module
• NDK/JNI unsupported in new plugin — extract to separate com.android.library module
• Compose resources crash without androidResources { enable = true } (CMP-9547)
• Consumer ProGuard rules silently dropped if not migrated to consumerProguardFiles.add(file(...)) in new DSL
• KSP requires version 2.3.4+ for AGP 9.0 compatibility

AGP 9.0 General Issues

• Built-in Kotlin conflicts — org.jetbrains.kotlin.android must be removed; kapt must be replaced
• BaseExtension removed — convention plugins using old DSL types need rewriting
• Variant APIs removed — applicationVariants, libraryVariants, variantFilter replaced by androidComponents
• R class non-final — switch on R fields fails in app modules; refactor to if/else
• targetSdk defaults to compileSdk — set explicitly to avoid unexpected behavior changes
• R8 rule changes — strict full mode, no global options in consumer rules
• Plugin compatibility — many plugins need updates or opt-out flags; check Plugin Compatibility section
• Convention plugins need refactoring — old android {} extension helpers are obsolete

Reference Files

• DSL Reference — side-by-side old→new DSL mapping
• Version Matrix — AGP/Gradle/KGP/IDE compatibility
• Plugin Compatibility — third-party plugin status and workarounds