Fox Authentication
Secure, passwordless sign-in for preSegment products.
Overview
Fox Authentication is preSegment’s in-house authentication system, built on Firebase Authentication and Firestore. It provides a single, consistent sign-in experience across all preSegment products — no passwords to create, remember, or leak.
How It Works
- Sign in with Google — Fox Authentication uses Google Sign-In as its sole identity provider. One click, no separate account to create.
- Returning users are recognized instantly and taken straight into the product.
- New users complete a short onboarding step — choosing a username and confirming their date of birth — before their account is created.
- Session handling — once signed in, a secure session is established using cookies, so you stay signed in across visits without re-authenticating every time.
Key Features
| Feature | Detail |
|---|---|
| Sign-in method | Google Sign-In only (no email/password) |
| Minimum age | 13 years |
| Username rules | Lowercase letters, numbers, and . _ - only |
| Session type | Cookie-based, with automatic tamper detection |
| Data stored | Username and date of birth only |
Security
Fox Authentication includes built-in tamper detection — if a session cookie is altered or no longer matches the signed-in account, the session is immediately invalidated and the user is signed out. This is designed to reduce the risk of session hijacking on the client side.
Where It’s Used
Fox Authentication currently powers sign-in for preSegment’s main platform, with more products planned to adopt it as they launch.