Configure Environment Variables
Environment variables allow you to configure application settings without hardcoding them into source files.
Create a .env file in the project root.
Add the following configuration:
Environment Variables
PORT
3000
NODE_ENV
development
Protect Environment Files
Never commit .env files containing secrets or credentials to a public repository. Add .env to .gitignore.
.env
PORT=3000
NODE_ENV=developmentPORT defines the HTTP server port. NODE_ENV identifies the current application environment.
Key Takeaways
Environment variables separate configuration from source code.
The server port can be changed without modifying application code.
Sensitive configuration must not be committed to Git.