Env Builder CLI #

env_builder_cli is a Dart CLI tool designed to automate the creation and maintenance of a Flutter package named env inside a packages/ folder. It helps Flutter developers manage multiple .env environment files by generating Dart code with Envied annotations, updating package dependencies, and managing Flutter project integration seamlessly.

Features #

• Accept multiple .env files (e.g. .env.development, .env.production, .env.staging, etc.).
• Create the packages/ directory if it does not exist.
• Create or update a Flutter package env within packages/env.
• Copy all specified .env.* files into packages/env/.
• Generate Dart files (env.dev.dart, env.prod.dart, env.stg.dart, etc.) within lib/src/.
• Generate lib/src/env.dart exporting all generated environment Dart files.
• Create or update pubspec.yaml inside packages/env with required dependencies.
• Automatically modify the root Flutter project’s pubspec.yaml to include env as a path dependency.
• Run flutter pub get automatically in the root project after setup.
• Minimal and clear command-line output.

Prerequisites #

• Dart SDK version 3.8.1
• Flutter SDK installed and added to your system path (for running flutter commands).
• Your Flutter project root directory (with an existing pubspec.yaml) contains the .env.* files you want to use.

Installing #

dart pub global activate env_builder_cli

Usage #

Create your .env.* files (e.g: .env, .env.development, .env.production, .env.staging, etc) inside your Flutter project's root and specify all your necessaries keys and values inside them.

Ex:

# App settings
BASE_URL = https://api.example.com/
API_KEY = supersecret

# Routes
LOGIN_URL = "login"
REGISTER_URL = "register/user"

Command #

You specify all the .env files that you want to use by separating the with comma.

env_builder --env-file=.env

Or

env_builder --env-file=.env.development, .env.production, .env.staging

Or

env_builder --env-file=.env.development

Wait till env_builder takes care of everything for you. Now, you can use your environment variables inside your application.

Ex:

/// In development mode, use AppFlavor.development(); => stands for .env.development
/// In production mode, use AppFlavor.production(); => stands for .env.production or .env in case you provide only that one
/// In staging mode, use AppFlavor.staging(); => stands for .env.staging

final appFlavor = AppFlavor.production();

class ApiService {
    final appBaseUrl = appFlavor.getEnv(Env.baseUrl);
    final apikey = appFlavor.getEnv(Env.apiKey);
}

• In development mode, use AppFlavor.development(). It stands for .env.development
• In production mode, use AppFlavor.production(). It stands for .env.production or .env in case you provide only that one.
• In staging mode, use AppFlavor.staging(). It stands for .env.staging

NB: you can name you .env.* file whatever you want. But, to call the appropriate AppFlavor, use the word after .env.

Ex:

.env.word ==> AppFlavor.word()

Environment File Encryption / Decryption #

This CLI provides a simple and secure way to encrypt and decrypt your environment files (.env). It helps protect sensitive information such as API keys, database credentials, and tokens when sharing code or committing to a repository.

Features #

• AES-based encryption with a password-derived key.
• CLI commands for quick usage (encrypt / decrypt).
• Compatible with .env files of any size.

Usage #

1. Encrypt a file

env_builder encrypt .env .env.enc --password superSecretKey

• .env → input file (plaintext environment file).
• .env.enc → output file (encrypted file).
• --password → secret used to derive the encryption key.

Result:

• A .env.enc file is created.
• Can be stored safely in your repo.

2. Decrypt a file

env_builder decrypt .env.enc .env --password superSecretKey

• .env.enc → input file (encrypted file).
• .env → output file (restored plaintext file).
• --password → must be the same password used during encryption.

Result:

• The original .env file is restored.

Notes #

• If the password does not match or the file is corrupted, you’ll get:

Error: Invalid password or corrupted file.

• For production use, always use a strong and private password.
• Do not commit decrypted .env files to version control. Only commit the encrypted version (.env.enc).

Example Workflow #

# Encrypt your .env before committing
env_builder encrypt .env .env.enc --password superSecretKey12345

# Remove the plaintext file (optional)
rm .env

# Later, restore it locally
env_builder decrypt .env.enc .env --password superSecretKey12345

With this, your team can safely share the .env.enc file while keeping secrets protected.