> ## Documentation Index
> Fetch the complete documentation index at: https://docs.major.build/llms.txt
> Use this file to discover all available pages before exploring further.

# Environment Variables

> Configure per-app environment variables.

Define environment variables per application in the **Environment Variables** panel. These variables are automatically injected into the live preview, build pipeline, and deployments.

## Live Reload

When you update or delete an environment variable, the preview automatically reloads with the changes — no restart needed.

## System Variables

System variables like `MAJOR_API_BASE_URL` cannot be overridden. Any variable with the `MAJOR_` prefix is reserved.

## Deployed Apps

After changing environment variables in a deployed app, click **Redeploy** to apply them to the live deployment. Environment variable changes do not take effect on deployed apps until redeployed.

## CLI

You can also manage environment variables from the CLI. Environment names are case-insensitive, so `--env staging` and `--env Staging` resolve to the same environment. See the [CLI Resource docs](/cli/resource) for details.