--- name: flutter-riverpod-state-management description: Implement reactive state management using Riverpod 3.x with code generation in Flutter. Use when defining providers, building AsyncNotifiers, or overriding providers in tests. metadata: triggers: files: - '**_provider.dart' - '**_notifier.dart' keywords: - riverpod - ProviderScope - ConsumerWidget - Notifier - AsyncValue - ref.watch - "@riverpod" --- # Riverpod State Management ## **Priority: P0 (CRITICAL)** Targets **Riverpod 3.x**. Notifier/AsyncNotifier codegen surface is unchanged from 2.x; Riverpod 3 adds automatic retry with backoff and pause/resume for offline — do not hand-roll retry logic that the framework already provides. ## Structure ```text lib/ ├── providers/ # Global providers and services └── features/user/ ├── providers/ # Feature-specific providers └── models/ # @freezed domain models ``` ## Provider Definition (Generator-First) Use `@riverpod` annotations for all provider definitions. See [implementation examples](references/implementation.md) for full provider and consumer patterns. ## Consuming Providers Use `ConsumerWidget` with `ref.watch()` and `AsyncValue.when()` for reactive UI. See [implementation examples](references/implementation.md). ## Implementation Guidelines - **Generator First**: Use `@riverpod` annotations. Avoid manual `Provider` definitions. - **Immutability**: Use `Freezed` for all state models. - **ref.watch()**: Inside `build()` to rebuild on changes. - **ref.listen()**: Inside `build()` for side-effects (navigation, dialogs). Never in provider init. - **ref.read()**: ONLY in callbacks (`onPressed`). - **Testing**: Override providers with `ProviderScope(overrides: [provider.overrideWithValue(Mock())])`. - **Linting**: Enable `riverpod_lint` and `custom_lint` for cycle detection. ## Anti-Patterns - **No side-effects in provider init**: Use `ref.listen()` in widgets instead. - **No BuildContext in Notifiers**: Never pass `BuildContext` into Notifier/Provider. - **No local provider instantiation**: Keep providers global; avoid dynamic creation. ## Related Topics - [flutter-layer-based-clean-architecture](../flutter-layer-based-clean-architecture/SKILL.md) - [flutter-dependency-injection](../flutter-dependency-injection/SKILL.md) - [flutter-testing](../flutter-testing/SKILL.md)