A Visual Guide to Clean Architecture

Interactively explore the layers, components, and data flows that make Clean Architecture a powerful pattern for building scalable and maintainable Flutter applications.

Why Clean Architecture?

This architecture provides a structured approach that yields significant, long-term advantages for complex projects. Here are the core benefits.

🧪

Enhanced Testability

Isolates business logic from UI and databases, making unit tests faster and simpler to write.

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Framework Independent

Your core logic doesn't depend on Flutter or other packages, making upgrades and migrations easier.

🔧

High Maintainability

Separation of concerns means changes in one layer don't break others, simplifying updates.

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Scalable & Flexible

The modular structure supports application growth and makes adding new features straightforward.

Explore the Layers

Clean Architecture is organized into concentric circles, with a strict rule: dependencies only point inwards. Click on any component to see its role, responsibilities, and a code example.

Presentation

View
ViewModel

Data

Repo Impl.
Data Source
Model (DTO)

Domain

Entity
Use Case
Repo Interface

Select a Component

Click an item in the diagram to learn about its role.

Data Flow in Action

Follow the journey of a user request from the UI to the data source and back. Click "Next Step" to see how each component interacts in a predictable, unidirectional flow.

View
ViewModel
Use Case
Repository
Data Source

Practical Guide

Explore recommended folder structures and best practices for implementing Clean Architecture in a real-world Flutter project.

Recommended Folder Structure

lib/
├── core/             # Cross-cutting concerns (utils, constants, failures)
├── domain/           # Core business logic (Entities, Use Cases, Repository interfaces)
│   ├── entities/
│   ├── repositories/ # Abstract interfaces (e.g., auth_repository.dart)
│   └── usecases/
├── data/             # Data implementations (Repositories, Data Sources, Models)
│   ├── datasources/  # Local (DAOs) & Remote (API clients)
│   ├── models/       # Data Transfer Objects (DTOs)
│   └── repositories/ # Concrete implementations (e.g., auth_repository_impl.dart)
└── presentation/     # UI Layer (Widgets, Screens, ViewModels)
    ├── features/     # Organized by feature (e.g., auth, learning)
│   │   ├── auth/
│   │   │   ├── screens/
│   │   │   └── viewmodels/
│   │   └── learning/
│   │       ├── screens/
│   │       └── viewmodels/
    ├── _shared/      # Shared widgets, styles
    └── widgets/      # General reusable widgets

When to Use It?

✅ Ideal For:

Large, complex applications with a long lifespan where testability, maintainability, and scalability are critical (e.g., banking, healthcare, major e-commerce apps).

⚠️ Caution For:

Small, simple apps or prototypes. The initial setup overhead can be significant and might slow down initial development (risk of over-engineering).