Dart/Flutter Patterns

When to Use

Use this skill when:

• Starting a new Flutter feature and need idiomatic patterns for state management, navigation, or data access
• Reviewing or writing Dart code and need guidance on null safety, sealed types, or async composition
• Setting up a new Flutter project and choosing between BLoC, Riverpod, or Provider
• Implementing secure HTTP clients, WebView integration, or local storage
• Writing tests for Flutter widgets, Cubits, or Riverpod providers
• Wiring up GoRouter with authentication guards

How It Works

This skill provides copy-paste-ready Dart/Flutter code patterns organized by concern:

1. Null safety — avoid !, prefer ?./??/pattern matching
2. Immutable state — sealed classes, freezed, copyWith
3. Async composition — concurrent Future.wait, safe BuildContext after await
4. Widget architecture — extract to classes (not methods), const propagation, scoped rebuilds
5. State management — BLoC/Cubit events, Riverpod notifiers and derived providers
6. Navigation — GoRouter with reactive auth guards via refreshListenable
7. Networking — Dio with interceptors, token refresh with one-ti…