Android build fails under AGP 9 when analytics-kotlin is also in the dependency graph: duplicate namespace 'com.segment.analytics'

Inspect the plugin's Android module and AndroidManifest.xml, then reproduce the failure with flutter build apk --debug using segment_analytics and com.segment.analytics.kotlin:android. Compare the namespace and package declarations with the issue's proposed unique namespace, and verify that the Android build completes without the duplicate-namespace error.

The plugin's Android module declares namespace 'com.segment.analytics' — the same namespace as Segment's native Android SDK (com.segment.analytics.kotlin:android, whose AAR manifest declares package="com.segment.analytics"). AGP 9 treats duplicate namespaces as a hard manifest-merger error, so any app that has both in its dependency graph no longer builds. This happens in practice with SDKs that embed analytics-kotlin, e.g. the Customer.io SDK (customer_io → io.customer.android:datapipelines → com.segment.analytics.kotlin:android).

Steps to reproduce

1. Flutter app with segment_analytics: 1.1.12 and AGP 9.x (tested with 9.1.0).
2. Add the native SDK to android/app/build.gradle (or any dependency that pulls it in, e.g. customer_io):

   dependencies {
       implementation "com.segment.analytics.kotlin:android:1.24.1"
   }
   

3. flutter build apk --debug

Result

[:segment_analytics] .../merged_manifest/debug/processDebugManifest/AndroidManifest.xml Error:
	Namespace 'com.segment.analytics' is used in multiple modules and/or libraries: :segment_analytics, com.segment.analytics.kotlin:android:1.24.1. Please ensure that all modules and libraries have a unique namespace.

Execution failed for task ':app:processDebugMainManifest'.
> Manifest merger failed with multiple errors, see logs

Fix

Rename the plugin's namespace to something unique, e.g. com.segment.analytics.flutter, and drop the deprecated package= attribute from AndroidManifest.xml. The namespace only affects the generated R/BuildConfig package, not the Dart API or Kotlin source packages. We've been running this patch in production: https://github.com/cheddar-me/analytics_flutter/commit/dda9906f4c3aed3c0b220f3c99447fafa2c3ddb8