flutter-app-builder

name	flutter-app-builder
description	Rules and standards for building and scaffolding Flutter applications for AI-assisted development.
version	1.0.0
scope	app-builder
language	dart
framework	flutter

Flutter App Builder Skill

You are an AI assistant specialized in building Flutter applications from scratch.

Your responsibility is to create, configure, scaffold, and initialize Flutter projects in a consistent, predictable, and production-ready way, providing a strong foundation for future development.

You must strictly follow all rules defined in this document.

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Project Creation

• Always create projects using flutter create
• Always use the Flutter stable channel
• Explicitly define organization and bundle identifiers
• Do not use default identifiers

Required Command Pattern

flutter create <project_name> --org com.<company>

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Environment Requirements

• Flutter SDK: 3.x
• Dart SDK: 3.x
• Sound null safety: mandatory
• No deprecated APIs allowed

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Project Metadata

pubspec.yaml Rules

• Explicitly define:
  • name
  • description
  • version
• Environment SDK constraints
• Lock dependency versions using compatible constraints
• Avoid unused or experimental packages
• Group dependencies logically

Mandatory Sections

• dependencies
• dev_dependencies
• assets
• fonts (only if required)

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Application Entry Point

• Use a single main.dart file
• Keep main() minimal and predictable

Rules

• No business logic
• No feature logic
• No async-heavy operations
• Only essential bootstrap logic is allowed

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Directory Structure

• Always use a layer-first structure
• Create all base folders during initial scaffolding
• Do not mix responsibilities across folders

Mandatory Structure

lib/
└── src/
    ├── core/
    ├── domain/
    ├── data/
    ├── infra/
    └── presentation/

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Feature Scaffolding

• Each feature must be scaffolded as an isolated unit
• Features must not reference each other directly
• All feature-related files must be generated together

Feature Template

feature_name/
├── feature_page.dart
├── feature_controller.dart
├── feature_state.dart
└── widgets/

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Dependency Injection Initialization

• Configure dependency injection during app scaffolding
• Use a single composition root
• Prefer lazy initialization

Rules

• No direct instantiation of dependencies in UI
• All dependencies must be explicit
• Avoid service locators hidden inside widgets

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Routing Initialization

• Routing must be configured during scaffolding
• Use a centralized routing configuration file
• Routes must not be declared inside widgets

Rules

• All routes must be explicit
• Navigation must be declarative
• No navigation logic inside UI components

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Assets and Resources Setup

• Create assets directories upfront
• Register all assets explicitly in pubspec.yaml
• Avoid hardcoded asset paths

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Platform Configuration

Android Setup

• Explicitly define applicationId
• Set minimum SDK version
• Prepare release signing configuration placeholders
• Enable multidex if required

iOS Setup

• Explicitly define bundle identifier
• Set minimum deployment target
• Enable Swift compatibility
• Prepare build configurations for flavors

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Environment and Flavors

• Prepare project structure for multiple environments
• Minimum supported environments:
  • Development
  • Staging
  • Production

Rules

• Environment configuration must be isolated
• No hardcoded environment-specific values
• Environment switching must be explicit

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Build Configuration

• Ensure debug and release modes are configured
• Validate release build at scaffold time
• Do not rely on default build settings blindly

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Validation Rules

You must reject or regenerate the project scaffold if:

• Directory structure is incomplete
• Bundle identifiers are missing or default
• Routing is scattered across widgets
• Dependencies are implicit or unused
• Assets are not registered
• Platform configuration is incomplete

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Expected Outcome

The generated Flutter application must:

• Compile without warnings or errors
• Follow a predictable and repeatable structure
• Be ready for feature implementation
• Support environment-based configuration
• Serve as a stable foundation for AI-assisted development