fix(expo): add Kotlin metadata version compatibility flag for clerk-android (#8152)

Author: chriscanin

.changeset/fix-kotlin-metadata-version.md

@@ -0,0 +1,5 @@
+---
+'@clerk/expo': patch
+---
+
+Add `-Xskip-metadata-version-check` Kotlin compiler flag to resolve metadata version mismatch errors when building Android apps with Expo SDK 54/55. The `clerk-android` dependency is compiled with Kotlin 2.3.x while Expo ships Kotlin 2.1.x, causing `:app:compileDebugKotlin` to fail.

packages/expo/android/build.gradle

@@ -54,7 +54,9 @@ android {
 
   kotlinOptions {
     jvmTarget = "17"
-    // clerk-android transitive deps (e.g. telemetry-api) still ship Kotlin 2.3.x metadata
+    // TODO: Remove once clerk-android pins its transitive deps to a Kotlin version compatible with Expo.
+    // clerk-android transitive deps (e.g. kotlinx-serialization-core:1.10.0) ship Kotlin 2.3.x metadata,
+    // but Expo SDK 54/55 uses Kotlin 2.1.x. This flag lets the 2.1.x compiler read 2.3.x metadata safely.
     freeCompilerArgs += ['-Xskip-metadata-version-check']
   }
 
@@ -75,7 +77,23 @@ android {
   }
 }
 
-// Note: kotlin-stdlib exclusions are handled in the clerk-android-ui dependency declaration
+// clerk-android is compiled with Kotlin 2.3.x, but Expo/RN projects typically use an older
+// Kotlin version (e.g. 2.1.x). This causes "incompatible version of Kotlin" metadata errors
+// at :app:compileDebugKotlin. Applying -Xskip-metadata-version-check allows the older
+// compiler to read 2.3.x metadata without failing.
+try {
+  rootProject.allprojects {
+    tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).configureEach {
+      compilerOptions {
+        freeCompilerArgs.add('-Xskip-metadata-version-check')
+      }
+    }
+  }
+} catch (Exception ignored) {
+  // Future Gradle versions with Isolated Projects may block cross-project configuration.
+  // In that case, users should add '@clerk/expo' to their app.json plugins array instead,
+  // which applies the flag via the config plugin's withClerkAndroid.
+}
 
 dependencies {
   // React Native