/flutter-feature-based-clean-architecture

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:
    - flutter feature
    - feature in flutter
    - flutter clean architecture
    - feature-based clean architecture
    - flutter domain layer
    - flutter presentation layer
    - lib/features
    - flutter architecture

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