# Production-Ready Flutter Mobile Application Rules

## 1. Core Development Philosophy

Build the application as a production-ready mobile product, not as a prototype or demo.

The primary goals are:

1. Stability
2. Security
3. Maintainability
4. Scalability
5. Performance
6. Accessibility
7. Excellent UX
8. Testability
9. Reliable networking
10. Production deployment readiness

Never sacrifice application stability just to implement a feature faster.

Before modifying existing code:

- Inspect the existing architecture.
- Inspect the affected feature.
- Inspect related models.
- Inspect API contracts.
- Inspect state management.
- Inspect navigation.
- Inspect authentication requirements.
- Inspect existing tests.
- Identify dependencies and side effects.

Do not blindly rewrite entire files.

Do not remove working functionality unless explicitly requested.

Do not replace a working architecture with another architecture without a clear technical reason.

---

# 2. Technology Stack

Preferred stack:

- Flutter
- Dart
- Android
- iOS
- Material 3 where appropriate
- Cupertino components where platform-specific behavior is beneficial
- REST/JSON APIs
- Repository Pattern
- MVVM
- Dependency Injection
- Immutable data models
- Async/await
- Streams where appropriate
- Automated testing

Prefer official Flutter and platform APIs before introducing unnecessary third-party packages.

Every dependency must have a clear purpose.

Avoid adding packages for functionality that can be implemented safely with the Flutter SDK.

---

# 3. Architecture

Use a layered architecture.

Minimum architecture:

```text
Presentation
    ↓
Domain / Business Logic
    ↓
Data
    ↓
Remote / Local Services


UI
 ↓
ViewModel
 ↓
UseCase
 ↓
Repository
 ↓
DataSource
 ↓
API / Local Database


lib/
│
├── app/
│   ├── app.dart
│   ├── router/
│   ├── theme/
│   └── config/
│
├── core/
│   ├── constants/
│   ├── errors/
│   ├── extensions/
│   ├── network/
│   ├── storage/
│   ├── security/
│   ├── utils/
│   └── widgets/
│
├── features/
│
│   ├── authentication/
│   │   ├── data/
│   │   ├── domain/
│   │   └── presentation/
│   │
│   ├── home/
│   │   ├── data/
│   │   ├── domain/
│   │   └── presentation/
│   │
│   ├── profile/
│   │   ├── data/
│   │   ├── domain/
│   │   └── presentation/
│   │
│   └── settings/
│       ├── data/
│       ├── domain/
│       └── presentation/
│
└── main.dart

HomeView
    ↓
HomeViewModel
    ↓
HomeRepository
    ↓
HomeApiService

ApiClient
    ↓
AuthApiService
UserApiService
ProductApiService
NotificationApiService

finally

App
 ↓
Create payment request
 ↓
Server validates product
 ↓
Payment provider
 ↓
Server verifies payment
 ↓
Server grants product
 ↓
App refreshes account