Environment variables

Give your app its API keys without putting them in the code.

Apps often need keys: a Supabase URL, a Stripe publishable key, an API endpoint. Keep them in your project’s environment variables instead of in the code.

Add a variable

1. Open Env

   Click Env in the project’s top bar.

2. Pick the scope

   Development is used by the preview, Production by production builds.

3. Save it

   Enter the name and value, and save.

Values are encrypted when they’re stored. After saving, the list shows only names and a fingerprint, never the value. Only workspace admins can reveal a value, and every reveal is logged.

Public and secret

The name decides who can see a value:

Name	Visibility	Where it goes
EXPO_PUBLIC_*	Public. Expo puts it in the app’s bundle, so anyone with the app can read it.	The preview and your builds
Anything else	Secret. Never given to the agent or the preview.	Your native builds only

Only use EXPO_PUBLIC_ names for keys that are meant to be public, like a publishable key. Appnetic warns you if a public value looks like a secret.

When the agent needs a key

The agent sees variable names, never their values. If it needs a key you haven’t added, it asks in the chat: paste the value into the card and save, or dismiss it. The request also shows in the Env drawer.