files containing real secrets to version control systems like GitHub. Instead, provide a .env.example .env.sample
# .env.development APP_NAME=MyDevApp API_URL=http://localhost:3000/$APP_NAME/api
.env.test.local → .env.test → .env
The .env.development file is a cornerstone of this philosophy, acting as a dedicated configuration hub specifically for your local development environment. .env.development
Understanding this hierarchy ensures that your local configurations don't accidentally overwrite critical settings. While specific order varies slightly by tool, the standard priority from generally looks like this:
Variables defined in .env.development are loaded in production. This prevents the accidental use of development API endpoints, debug flags, or test credentials in a live environment.
A .env file—short for "environment"—is a plain-text file that stores environment variables as simple key-value pairs, used to configure important aspects of an application, such as database connections, API endpoints, or debugging flags. files containing real secrets to version control systems
A .env.development file is a specialized version of a standard environment configuration file used primarily by modern JavaScript frameworks and build tools. It stores "development-only" variables—like local database credentials or mock API keys—to keep your local coding environment distinct from production. What is a .env.development File?
In modern software development, separating your configuration from your actual application code is a strict requirement. This practice, popularized by the Twelve-Factor App methodology, ensures security, flexibility, and consistency across different deployment stages.
Here's an example Next.js development configuration: While specific order varies slightly by tool, the
Understanding where .env.development fits in the broader ecosystem of environment files is essential:
For production environments, avoid using .env files entirely. Instead:
: Follow the Unix convention of KEY_NAME=value . Avoid spaces or special characters in the key.
In backend environments, all variables loaded from .env.development are attached directly to the global process.env object. You can access them anywhere in your backend code. javascript
# Development environment variables