.env.local

How .env.local behaves depends entirely on your toolchain. Let’s look at the three most common scenarios.

Do not put spaces around the = .

.env .env.local

At its heart, .env.local is a text file used to define environment variables that are specific to a developer's local machine. Unlike a standard .env file, which might contain default settings shared across a team, .env.local is designed to be like Git. This creates a critical layer of security: developers can use their own private credentials for local testing without the risk of accidentally committing them to GitHub or GitLab. Security and Best Practices .env.local

In your Express application, you can load the environment variables using a library like dotenv : Security and Best Practices In your Express application,

project-root/ ├── .gitignore # Must contain .env.local ├── .env # Defaults (safe to commit) ├── .env.local # Local overrides (DO NOT COMMIT) ├── .env.development # Dev env defaults └── .env.test # Test env defaults .env .env.local At its heart

env.local for web development, specifically tailored for frameworks like Next.js and Vite. Keeping Secrets Secret: Why You Need .env.local