Setting Up Shared App Config

What you'll learn

• Generating the shared config package with envied integration
• Managing environment variables across flavors (dev, staging, production)
• Using compile-time obfuscated env var injection
• Accessing config values throughout your monorepo

Prerequisites

• An existing Archipelago monorepo (see Monorepo Scaffolding)

Step 1: Generate the Shared App Config

archipelago generate shared_app_config

You will be prompted for:

• appName — MyApp (must match your monorepo app name)
• isForMonorepo — true

Or use a config file:

{
  "appName": "MyApp",
  "isForMonorepo": true
}

archipelago generate shared_app_config --config config.json

Step 2: Understand the Generated Structure

shared/
└── app_config/
    ├── lib/src/
    │   ├── app_config.dart           # Main config class
    │   ├── env/
    │   │   ├── env.dart              # @Envied annotated class
    │   │   └── env.g.dart            # Generated (obfuscated values)
    │   └── flavor.dart               # Flavor enum (dev, staging, prod)
    ├── .env.development              # Dev environment variables
    ├── .env.staging                  # Staging environment variables
    ├── .env.production               # Production environment variables
    └── pubspec.yaml

Step 3: Define Your Environment Variables

Edit the .env.* files for each flavor:

# .env.development
BASE_URL=https://api-dev.myapp.com
SENTRY_DSN=
ENABLE_LOGGING=true

# .env.production
BASE_URL=https://api.myapp.com
SENTRY_DSN=https://key@sentry.io/123
ENABLE_LOGGING=false

Step 4: Add Variables to the Envied Class

// app_config/lib/src/env/env.dart
@Envied(path: '.env', obfuscate: true)
abstract class Env {
  @EnviedField(varName: 'BASE_URL')
  static const String baseUrl = _Env.baseUrl;

  @EnviedField(varName: 'SENTRY_DSN', defaultValue: '')
  static const String sentryDsn = _Env.sentryDsn;

  @EnviedField(varName: 'ENABLE_LOGGING')
  static const bool enableLogging = _Env.enableLogging;
}

Run code generation after adding fields:

dart run build_runner build --delete-conflicting-outputs

Step 5: Use Config in Your App

// Access from anywhere in the monorepo
import 'package:app_config/app_config.dart';

final apiUrl = Env.baseUrl;
final dsn = Env.sentryDsn;

Why Envied Over dart-define

Approach	Downside
--dart-define	Values visible in process list, no obfuscation
envied	Compile-time injection with string obfuscation

Envied generates obfuscated Dart code so secrets are not stored as plain strings in the compiled binary.

Common Customizations

Customization	Where to Change
Add new env vars	.env.* files + env.dart
Change flavors	flavor.dart enum
Add per-feature config	Create feature-specific @Envied classes
CI/CD secrets	Inject .env files from CI secret store

Next Steps

• Set up Shared Dependencies for centralized package management
• Configure build_prepare for flavor-based builds