Android build errorGradle: “Execution failed for task ':app:...'”

What the failing task tells you, and the fix

1. 01

   Read the cause, not the task name

   “A message that starts with Execution failed for task means the failure happened while running that task, not while configuring the build.” Gradle, Troubleshooting builds

   Gradle prints the failing task first and nests the underlying error under it. Read to the deepest line, and rerun with --stacktrace or --info when the message is cut short.

   ./gradlew assembleDebug --stacktrace
   # Windows: gradlew.bat assembleDebug --stacktrace

2. 02

   compileDebugKotlin or compileDebugJavaWithJavac

   A real compile error in your code or a plugin, or a version mismatch: Android Gradle Plugin 8 needs JDK 17 or newer, and Java and Kotlin must target the same JVM version. Point Android Studio’s Gradle JDK at JDK 17 or 21 and set one target for both. The kotlin block sits at the top level of the module’s build.gradle.kts, outside android, and jvmToolchain needs JDK 17 installed or a toolchain resolver plugin.

   android {
     compileOptions {
       sourceCompatibility = JavaVersion.VERSION_17
       targetCompatibility = JavaVersion.VERSION_17
     }
   }
   kotlin { jvmToolchain(17) }

3. 03

   checkDebugAarMetadata

   A dependency was built against a newer Android API than your compileSdk. The message names the library and the version it needs. Raise compileSdk (not minSdk) to at least that version. A higher compileSdk, or the library itself, can also need a newer Android Gradle Plugin; the message says which version.

   android {
     compileSdk = 36
   }

4. 04

   mergeDebugResources, processDebugMainManifest or mergeDexDebug

   “When one failure wraps another, the underlying cause is prefixed with >.” Gradle, Troubleshooting builds

   Resource tasks fail on a bad XML file, an invalid file name in res/, or a duplicate resource; manifest tasks fail on merge conflicts; dex tasks fail on D8 errors such as the 64K method limit (duplicate classes usually fail earlier, in checkDebugDuplicateClasses). The nested message names the file or class, so fix that one.

Checked against the vendor’s docs on November 8, 2026: Gradle: Troubleshooting builds.

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