---
name: Firebase Auth Isolation Pattern
description: FirebaseAuthService in core/lib/src/services/auth/ abstracts all Firebase Auth SDK operations so feature packages never import firebase_auth directly
type: project
---

`FirebaseAuthService` (interface) and `FirebaseAuthServiceImpl` live in `core/lib/src/services/auth/firebase_auth_service.dart`.

Registered in `CoreModule` as `i.addLazySingleton<FirebaseAuthService>(FirebaseAuthServiceImpl.new)`.

Exported from `core.dart`.

**Why:** Architecture rule requires firebase_auth only in core. Features inject `FirebaseAuthService` via DI.

**How to apply:** Any new feature needing Firebase Auth operations (sign-in, sign-out, phone verification, get current user info) should depend on `FirebaseAuthService` from `krow_core`, not import `firebase_auth` directly. The service provides: `authStateChanges`, `currentUserPhoneNumber`, `currentUserUid`, `verifyPhoneNumber`, `signInWithPhoneCredential` (returns `PhoneSignInResult`), `signInWithEmailAndPassword`, `signOut`, `getIdToken`.