> ## Documentation Index
> Fetch the complete documentation index at: https://vlyai-1c28d863.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Firebase Auth

> Google's auth platform. Mature, broad provider support, generous free tier.

[Firebase Authentication](https://firebase.google.com/products/auth) is Google's auth platform. Wide provider support (email, phone, OAuth, anonymous), generous free tier.

<Note>
  Full setup walkthrough being written.
</Note>

## When to pick

* You're already using other Firebase services.
* You need phone-number auth at scale (cheap).
* You want anonymous-then-upgrade auth flows.

## Setup

Firebase config (apiKey, authDomain, projectId) as `VITE_FIREBASE_*` env vars. Server-side service account JSON in vly secrets.

## Related

<CardGroup cols={3}>
  <Card title="Built-in auth" icon="lock" href="/features/auth/built-in-auth">
    Default vly auth.
  </Card>

  <Card title="Clerk" icon="user-circle" href="/integrations/clerk">
    UI-first alternative.
  </Card>

  <Card title="Twilio" icon="phone" href="/integrations/twilio">
    Phone auth alternative.
  </Card>
</CardGroup>


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