Flutter Architecture Template with Riverpod

Why architecture matters from day one

Most Flutter projects become unmaintainable after 6 months. Business logic mixed with UI, untestable code, and features that break other features. A solid architecture prevents this.

Add features without fear

Clear boundaries mean new code does not break existing features

Test with confidence

Separated layers allow unit testing without mocking everything

Onboard developers faster

Consistent patterns mean less time explaining where code goes

Swap backends easily

Firebase to Supabase? Change one layer, UI stays untouched

FOUNDATION

Three-Layer Architecture

A battle-tested pattern that separates your app into Data, Domain, and Presentation layers. Each layer has one job, making your code predictable and maintainable. This is the same architecture used by large-scale production apps.

Data Layer

APIs, storage, external services

Domain Layer

Business logic and repositories

Presentation Layer

UI, state, user interactions

Clear boundaries

Each layer only talks to adjacent layers

STATE MANAGEMENT

Riverpod Built-In

Riverpod is the modern standard for Flutter state management. Compile-time safety, easy testing, and reactive updates. No more Provider context issues or setState spaghetti.

Type-safe

Compile-time errors instead of runtime crashes

Testable

Override any provider in tests

Reactive

UI updates automatically when state changes

No context

Access state anywhere without BuildContext

ORGANIZATION

Modular Folder Structure

Features are self-contained modules. Each module has its own API, domain, and UI folders. Add, remove, or update features independently without touching unrelated code.

Feature modules

Auth, payments, settings - all separate

Core layer

Shared code like user state and theme

Consistent naming

Find any file in seconds

Scalable

Works for 10 or 100+ files

Save 3 months of work

One command. Pick your modules. Firebase or Supabase auto-configured. Start building what matters.

See the pattern in action

Here is how data flows through the layers. The UI never touches the API directly - it goes through the domain layer where business logic lives.

Easy to test

Fake the API, test the notifier logic in isolation

Easy to change

Switch from REST to GraphQL - only API layer changes

Easy to understand

New developers know exactly where to look.

Built on 7 core principles

Separation of Concerns

Each component has one job and does it well

Testability

Every layer designed to be tested independently

Scalability

Add features without restructuring existing code

Maintainability

Updates and bug fixes stay contained

Performance

Riverpod rebuilds only what changed

Modularity

Features can be added or removed independently

Reactivity

State changes propagate automatically to the UI

Folder structure that scales

Every generated project follows this structure. Whether you are building a simple app or a complex platform, you will always know where code belongs.

lib/
├── core/
│   ├── data/          # Shared APIs, entities, models
│   ├── states/        # Global states (user, subscription)
│   ├── initializer/   # App startup services
│   └── widgets/       # Shared UI components
│
└── modules/
    └── auth/          # feature module - independent
        ├── api/       # Auth API calls
        ├── entities/  # Auth data models
        ├── domain/    # Auth business logic
        ├── providers/ # Auth Riverpod providers
        └── ui/        # Auth screens & widgets

Architecture that makes testing easy

Good architecture is testable architecture. When layers are separated, you can test business logic without spinning up the entire app. We use fakes instead of mocks - they test real behavior, not implementation details.

Fakes over Mocks

Test business logic, not implementation. Changes to code do not break tests unless behavior changes.

Unit Tests

Test repositories and notifiers in isolation. Fast feedback, easy debugging.

Widget Tests

AppWidgetTester extension creates realistic test environments with navigation and state.

Multi-Device Testing

DeviceTestExtension runs tests across multiple screen sizes automatically.

Testing philosophy

We do not chase 100% coverage. We test what matters: business logic, user flows, edge cases. Write tests before code. Fix bugs by writing a failing test first, then fix it.

Start with architecture that works

Skip months of architectural decisions. Get a production-ready structure from day one.

Production-ready architecture template for Flutter