Environment Variables

The Environment Variables section on the container Docker Settings page holds the key/value pairs passed to your container at runtime. Use them for anything the container reads from its environment, like connection strings, feature flags, or API keys.

Managing variables

The section starts empty, with "No environment variables configured". Use Add variable to add a key/value row, and repeat for each variable. Edit the values and use Save to stage the change, which is applied through the project deploy flow.

Best practices

Name each variable so its purpose is obvious, and prefix related ones so they group together (for example DB_, SMTP_). Keep credentials out of the image: pass them in here instead of baking them into the build. In your app, fall back to sensible defaults for optional variables and check the critical ones at startup.