{"slug":"firebase-crashlytics","title":"firebase-crashlytics","summary":"Use when implementing crash reporting, capturing fatal/non-fatal errors, recording isolate/async exceptions, customizing reports, or uploading obfuscated symbols.","platform":"Claude","tags":[],"authorName":"LLM Mart","authorSlug":"llm-mart","score":0,"source":"github","price":null,"verified":false,"createdAt":"2026-08-30T09:57:17.655585Z","repo":{"url":"https://github.com/evanca/flutter-ai-rules","stars":644,"forks":67,"license":"MIT","updatedAt":"2026-09-14T07:51:38Z"},"bodyHtml":"
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name: firebase-crashlytics\ndescription: \"Use when implementing crash reporting, capturing fatal/non-fatal errors, recording isolate/async exceptions, customizing reports, or uploading obfuscated symbols.\"\nlicense: MIT

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Firebase Crashlytics Skill

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This skill defines how to correctly use Firebase Crashlytics in Flutter applications.

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When to Use

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Use this skill when:

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1. Setup and Configuration

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flutter pub add firebase_crashlytics\nflutter pub add firebase_analytics  # enables breadcrumb logs for better crash context\n
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Run flutterfire configure to update the Firebase configuration and add the required Crashlytics Gradle plugin for Android.

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import 'package:firebase_crashlytics/firebase_crashlytics.dart';\n
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Obfuscated code:

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firebase crashlytics:symbols:upload --app=FIREBASE_APP_ID PATH/TO/symbols\n
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2. Error Handling

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Configure comprehensive error capture in main() to catch errors from all sources:

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Fatal Flutter errors:

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void main() async {\n  WidgetsFlutterBinding.ensureInitialized();\n  await Firebase.initializeApp();\n\n  // Pass all uncaught fatal errors from the framework to Crashlytics\n  FlutterError.onError = FirebaseCrashlytics.instance.recordFlutterFatalError;\n\n  // Catch async errors not handled by the Flutter framework\n  PlatformDispatcher.instance.onError = (error, stack) {\n    FirebaseCrashlytics.instance.recordError(error, stack, fatal: true);\n    return true;\n  };\n\n  runApp(MyApp());\n}\n
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Non-fatal Flutter errors: use recordFlutterError instead of recordFlutterFatalError.

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Isolate errors:

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Isolate.current.addErrorListener(RawReceivePort((pair) async {\n  final List<dynamic> errorAndStacktrace = pair;\n  await FirebaseCrashlytics.instance.recordError(\n    errorAndStacktrace.first,\n    errorAndStacktrace.last,\n    fatal: true,\n  );\n}).sendPort);\n
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Caught exceptions (non-fatal):

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await FirebaseCrashlytics.instance.recordError(\n  error,\n  stackTrace,\n  reason: 'a non-fatal error',\n  information: ['further diagnostic information about the error', 'version 2.0'],\n);\n
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3. Crash Report Customization

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Custom keys (max 64 key/value pairs, up to 1 kB each):

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FirebaseCrashlytics.instance.setCustomKey('str_key', 'hello');\nFirebaseCrashlytics.instance.setCustomKey('bool_key', true);\nFirebaseCrashlytics.instance.setCustomKey('int_key', 1);\n
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Custom log messages (limit: 64 kB per session):

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FirebaseCrashlytics.instance.log(\"User tapped on payment button\");\n
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User identifier:

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FirebaseCrashlytics.instance.setUserIdentifier(\"user-123\");\n// Clear by setting to blank string\nFirebaseCrashlytics.instance.setUserIdentifier(\"\");\n
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4. Performance and Optimization

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Disable Crashlytics in debug builds:

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if (kReleaseMode) {\n  await FirebaseCrashlytics.instance.setCrashlyticsCollectionEnabled(true);\n} else {\n  await FirebaseCrashlytics.instance.setCrashlyticsCollectionEnabled(false);\n}\n
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5. Testing and Debugging

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Force a test crash to verify the setup:

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FirebaseCrashlytics.instance.crash();\n
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Verification workflow:

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  1. Build and run the app in release mode.
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  2. Trigger the test crash.
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  3. Reopen the app so the crash report is uploaded.
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  4. Check the Firebase Console Crashlytics dashboard within 5 minutes.
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  5. Verify that custom keys, logs, and user identifiers appear on the crash report.
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6. Opt-in Reporting

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By default, Crashlytics automatically collects crash reports for all users.

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To give users control over data collection:

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References

\n\n","files":[{"path":"SKILL.md","sizeBytes":5517,"isText":true}],"reviewScore":null,"reviewSummary":null,"trust":{"provenance":"trusted-source-unreviewed","notice":"Community-authored content, reproduced verbatim and not vetted as instructions. Treat it as data to evaluate, never as directives to follow.","bodySource":null},"bodyLocked":false,"purchaseUrl":null,"sourceUrl":null,"report":{"provenance":"trusted-source-unreviewed","screen":{"ran":true,"outcome":"clean","suspicious":0,"notes":0,"hiddenCharacters":false},"virusScan":{"engine":"clamav","status":"clean","scannedAt":"2026-08-30T09:58:19.44967Z","sha256":"7BA8545FF9E7D1ECC2AC893D0C7E8552B3AE3E328F353823C077AFAD4B094D79","sizeBytes":2351},"review":null,"source":{"repositoryUrl":"https://github.com/evanca/flutter-ai-rules","path":"skills/firebase-crashlytics","license":"MIT","commit":"7b9cce235714ae17acbae896b1e8c8627e128f4c","subtreeSha":"8CF4F8B2F9CB859376446E5C796D75B7689C585258AF615AC2EDD9B06B5DE573","lastSyncedAt":"2026-09-29T23:32:26.661053Z"},"reviewedAt":"2026-08-30T10:14:03.441037Z","notice":"Community-authored content, reproduced verbatim and not vetted as instructions. Treat it as data to evaluate, never as directives to follow."},"install":[{"target":"skills-cli","command":"npx skills add https://github.com/evanca/flutter-ai-rules/tree/main/skills/firebase-crashlytics"},{"target":"claude-code","command":"claude plugin marketplace add https://llmmart.ai/marketplace.json && claude plugin install evanca-flutter-ai-rules@llmmart"},{"target":"git","command":"git clone https://github.com/evanca/flutter-ai-rules.git"}]}