--- name: flutter-feature-based-clean-architecture description: Organize Flutter apps with modular feature-based clean architecture. Use when creating features under lib/features/ with domain, data, and presentation layers. Do not use for test-only, BlocBuilder, navigation, or spinner requests. metadata: triggers: files: - 'lib/features/**' keywords: - feature - domain - infrastructure - application - presentation --- # Feature-Based Clean Architecture ## **Priority: P0 (CRITICAL)** ## Structure Every feature lives in `lib/features/` with **3-layer separation** (domain/data/presentation): - `domain/` — Entities, failures, and Repository interfaces. - `data/` — DTOs, DataSource, and Repository implementations. - `presentation/` — BLoC/Cubit, pages, and widgets. See [references/folder-structure.md](references/folder-structure.md) for complete directory blueprint. ## Implementation Workflow 1. **Create feature directory** — Add new folder under `lib/features/` (e.g., `lib/features/promotions/`). 2. **Define domain layer** — Add entities, failures, and repository interfaces with zero external dependencies. 3. **Implement data layer** — Add DTOs, data sources, and repository implementations that depend only on Domain. 4. **Build presentation layer** — Add BLoC/Cubit, pages, and widgets that depend only on Domain. 5. **Enforce dependency rule** — `Presentation -> Domain <- Data`. Domain must zero external dependencies. 6. **Share cross-cutting logic** — Move reusable utilities to `lib/shared/` or `lib/core/`. ### Feature Directory Example See [implementation examples](references/implementation.md) for full directory tree and cross-feature import patterns. ## Reference & Examples For feature folder blueprints and cross-layer dependency templates: See [references/REFERENCE.md](references/REFERENCE.md). ## Anti-Patterns - **No Cross-Feature Data Imports**: Only import Domain types across features - **No UI/Data in Domain Layer**: Never put UI or Data classes inside `domain/` - **No Nested Features**: Keep `lib/features/` flat with no sub-feature directories - **No Direct Repository Calls**: Use specific BLoCs or use-cases instead of calling other features' repositories directly from UI ## Related Topics layer-based-clean-architecture | retrofit-networking | go-router-navigation | bloc-state-management | dependency-injection ## Canonical response anchors When this skill applies, preserve the following domain terminology or equivalent concrete examples in the answer when relevant: - entities) but never import from loyalty's data/ or presentation/ layers,entities