Firebase Auth + Better Auth

better-auth-firebase-auth bridges Firebase Authentication identity providers into Better Auth sessions. Firebase verifies the user; Better Auth owns the session, users, and plugins.

Package: better-auth-firebase-auth — GitHub · npm

Decision: Firebase Phone Auth vs Better Auth phoneNumber plugin

Use better-auth-firebase-auth when:

• You want phone auth without setting up Twilio or any SMS provider
• You are already using Firebase in your project
• You want Google to manage SMS delivery, reCAPTCHA, and fraud prevention

Use Better Auth's built-in phoneNumber plugin when:

• You want no Firebase dependency
• You need a specific SMS provider for compliance or cost reasons