diff --git a/docs/01-architecture/authentication-architecture.md b/docs/01-architecture/authentication-architecture.md
new file mode 100644
index 0000000..d0c3b8d
--- /dev/null
+++ b/docs/01-architecture/authentication-architecture.md
@@ -0,0 +1,235 @@
+# Authentication Architecture
+
+This document describes the current authentication architecture using dependency injection and service-based patterns.
+
+## Overview
+
+The authentication system has been refactored from a legacy global composable approach to a modern dependency injection pattern. This eliminates timing issues, improves maintainability, and provides a single source of truth for authentication state.
+
+## Architecture Components
+
+### 1. AuthService (Core Service)
+**Location**: `src/modules/base/auth/auth-service.ts`
+
+The `AuthService` is a singleton service that extends `BaseService` and provides:
+- Reactive authentication state management
+- LNBits API integration
+- Event-driven authentication lifecycle
+- Automatic token management
+
+**Key Features**:
+```typescript
+export class AuthService extends BaseService {
+  // Public reactive state
+  public isAuthenticated = ref(false)
+  public user = ref<User | null>(null)
+  public isLoading = ref(false)
+  public error = ref<Error | null>(null)
+  
+  // Computed properties for compatibility
+  public currentUser = computed(() => this.user.value)
+  public userDisplay = computed(() => { /* user display logic */ })
+  
+  // Methods
+  async login(credentials: LoginCredentials): Promise<void>
+  async register(data: RegisterData): Promise<void>
+  async logout(): Promise<void>
+  async checkAuth(): Promise<boolean>
+  async updatePassword(current: string, newPass: string): Promise<void>
+  async updateProfile(data: Partial<User>): Promise<void>
+}
+```
+
+### 2. useAuthService Composable (API Layer)
+**Location**: `src/composables/useAuthService.ts`
+
+The `useAuthService` composable provides a clean, unified API that bridges Vue components with the injected AuthService:
+
+```typescript
+export function useAuth() {
+  const authService = injectService(SERVICE_TOKENS.AUTH_SERVICE) as AuthService
+  
+  return {
+    // State (reactive refs from service)
+    currentUser: authService.currentUser,
+    isAuthenticated: authService.isAuthenticated,
+    isLoading: authService.isLoading,
+    error: authService.error,
+    userDisplay: authService.userDisplay,
+    
+    // Methods (delegated to service)
+    initialize: () => authService.initialize(),
+    login: (credentials: any) => authService.login(credentials),
+    register: (data: any) => authService.register(data),
+    logout: () => authService.logout(),
+    checkAuth: () => authService.checkAuth()
+  }
+}
+```
+
+### 3. Dependency Injection Container
+**Location**: `src/core/di-container.ts`
+
+The DI container manages service registration and injection:
+
+```typescript
+// Service registration (in base module)
+container.provide(SERVICE_TOKENS.AUTH_SERVICE, authService)
+
+// Service consumption (in components/other services)
+const authService = injectService(SERVICE_TOKENS.AUTH_SERVICE) as AuthService
+```
+
+## Usage Patterns
+
+### In Vue Components (Recommended)
+```vue
+<script setup lang="ts">
+import { useAuth } from '@/composables/useAuthService'
+
+const auth = useAuth()
+
+// Access reactive state
+const isAuthenticated = auth.isAuthenticated
+const currentUser = auth.currentUser
+
+// Call methods
+const handleLogin = async (credentials) => {
+  await auth.login(credentials)
+}
+</script>
+```
+
+### In Services (Direct Injection)
+```typescript
+import { injectService, SERVICE_TOKENS } from '@/core/di-container'
+import type { AuthService } from '@/modules/base/auth/auth-service'
+
+export class SomeService extends BaseService {
+  private get authService(): AuthService {
+    return this.dependencies.get('AuthService') as AuthService
+  }
+  
+  async someMethod() {
+    const user = this.authService.user.value
+    if (user?.pubkey) {
+      // Use authenticated user data
+    }
+  }
+}
+```
+
+## Benefits of New Architecture
+
+### 1. **Single Source of Truth**
+- All authentication state managed by AuthService singleton
+- No more timing issues between global and injected auth
+- Consistent state across all modules and components
+
+### 2. **Dependency Injection Benefits**
+- Loose coupling between components and auth logic
+- Easy to test (can inject mock services)
+- Modular architecture with clear boundaries
+- Service lifecycle management
+
+### 3. **Improved Maintainability**
+- Centralized authentication logic
+- Event-driven architecture for auth state changes
+- Clear separation of concerns
+- Eliminated complex dual-auth detection patterns
+
+### 4. **Performance Improvements**
+- No duplicate service instances
+- Efficient reactive state management
+- Reduced complexity in components
+
+## Migration Guide
+
+### Before (Legacy Pattern)
+```typescript
+// ❌ Old global composable pattern
+import { auth } from '@/composables/useAuth'
+
+// Direct access to global singleton
+const isAuthenticated = auth.isAuthenticated.value
+```
+
+### After (Current Pattern)
+```typescript
+// ✅ New dependency injection pattern
+import { useAuth } from '@/composables/useAuthService'
+
+const auth = useAuth()
+const isAuthenticated = auth.isAuthenticated.value
+```
+
+## Service Integration
+
+### Module Registration
+Each module that needs authentication access should:
+
+1. **Declare dependency** on AuthService in module metadata
+2. **Access via dependency injection** using the DI container
+3. **Use reactive state** from the service for UI updates
+
+### Example Service Integration
+```typescript
+export class ChatService extends BaseService {
+  protected readonly metadata = {
+    name: 'ChatService',
+    dependencies: ['AuthService'] // Declare dependency
+  }
+  
+  async sendMessage(content: string) {
+    // Access auth through DI
+    const user = this.authService.user.value
+    if (!user?.pubkey || !user?.prvkey) {
+      throw new Error('Authentication required for messaging')
+    }
+    
+    // Use authenticated user data
+    const encrypted = await nip04.encrypt(user.prvkey, recipientPubkey, content)
+    // ... rest of implementation
+  }
+}
+```
+
+## Error Handling
+
+The authentication system provides comprehensive error handling:
+
+1. **Network Errors**: Handled in AuthService with proper error propagation
+2. **Invalid Credentials**: Clear error messages passed to components
+3. **Token Expiration**: Automatic logout with cleanup
+4. **Service Unavailable**: Graceful degradation with retry logic
+
+## Testing
+
+The dependency injection architecture makes testing straightforward:
+
+```typescript
+// Mock the auth service for testing
+const mockAuthService = {
+  isAuthenticated: ref(true),
+  currentUser: ref({ id: 'test-user', username: 'test' }),
+  login: vi.fn(),
+  logout: vi.fn()
+}
+
+// Inject mock in tests
+container.provide(SERVICE_TOKENS.AUTH_SERVICE, mockAuthService)
+```
+
+## Security Considerations
+
+1. **Token Storage**: Secure storage in localStorage with automatic cleanup
+2. **API Integration**: All requests authenticated via LNBits tokens
+3. **State Management**: Reactive state prevents stale authentication data
+4. **Service Isolation**: Authentication logic isolated in dedicated service
+
+## Future Enhancements
+
+1. **Token Refresh**: Automatic token refresh before expiration
+2. **Multi-Factor Authentication**: Support for additional auth factors
+3. **Session Management**: Enhanced session handling and persistence
+4. **Audit Logging**: Authentication event logging for security
\ No newline at end of file
diff --git a/docs/02-modules/chat-module/integration.md b/docs/02-modules/chat-module/integration.md
index 753265f..bd07af6 100644
--- a/docs/02-modules/chat-module/integration.md
+++ b/docs/02-modules/chat-module/integration.md
@@ -24,14 +24,15 @@ A Vue component that provides the chat interface with:
 - Encrypted message exchange
 - Connection status indicators
 
-### 2. useNostrChat.ts
-**Location**: `src/composables/useNostrChat.ts`
+### 2. ChatService
+**Location**: `src/modules/chat/services/chat-service.ts`
 
-A composable that handles:
-- Nostr relay connections
+A service-based architecture that handles:
+- Nostr relay connections via dependency injection
 - Message encryption/decryption
-- User authentication with LNBits
+- User authentication through AuthService
 - Real-time message subscription
+- Integration with modular service architecture
 
 ### 3. ChatPage.vue
 **Location**: `src/pages/ChatPage.vue`
@@ -83,9 +84,10 @@ Response:
 ## Features
 
 ### 1. User Integration
-- Automatically loads peers from LNBits user database
-- Uses existing `pubkey` and `prvkey` fields
-- Admin-only access to private keys for messaging
+- Automatically loads peers from LNBits user database via dependency injection
+- Uses existing `pubkey` and `prvkey` fields from AuthService
+- Authentication managed through centralized AuthService
+- No dual authentication issues - single source of truth
 
 ### 2. Nostr Relay Integration
 - Connects to multiple Nostr relays for redundancy
diff --git a/docs/03-core-services/authentication.md b/docs/03-core-services/authentication.md
index 71c23fd..0d99f72 100644
--- a/docs/03-core-services/authentication.md
+++ b/docs/03-core-services/authentication.md
@@ -78,11 +78,74 @@ The application uses the following LNBits API endpoints:
 - Route protection for authenticated pages
 - Secure logout with token cleanup
 
-## Migration from Nostr
+## Architecture
 
-The following components have been removed or replaced:
+The authentication system uses a **dependency injection pattern** for clean modular architecture:
 
-- `useIdentity.ts` → `useAuth.ts`
+### Core Components
+
+1. **AuthService** (`src/modules/base/auth/auth-service.ts`)
+   - Singleton service that manages authentication state
+   - Handles API calls to LNBits
+   - Provides reactive state management
+
+2. **useAuthService** (`src/composables/useAuthService.ts`)  
+   - Wrapper composable that provides unified access to AuthService
+   - Uses dependency injection to access the service
+   - Provides consistent API for all components
+
+3. **Dependency Injection Container** (`src/core/di-container.ts`)
+   - Manages service registration and injection
+   - Ensures single source of truth across modules
+
+### Usage Pattern
+
+Components access authentication through the `useAuth()` composable:
+
+```typescript
+import { useAuth } from '@/composables/useAuthService'
+
+export default defineComponent({
+  setup() {
+    const auth = useAuth()
+    
+    // Access authentication state
+    const isAuthenticated = auth.isAuthenticated
+    const currentUser = auth.currentUser
+    
+    // Call authentication methods
+    const login = (credentials) => auth.login(credentials)
+    const logout = () => auth.logout()
+    
+    return {
+      isAuthenticated,
+      currentUser,
+      login,
+      logout
+    }
+  }
+})
+```
+
+### Service Registration
+
+The AuthService is registered in the base module and made available through dependency injection:
+
+```typescript
+// In base module
+container.provide(SERVICE_TOKENS.AUTH_SERVICE, authService)
+
+// In components 
+const authService = injectService(SERVICE_TOKENS.AUTH_SERVICE)
+```
+
+## Migration from Legacy Architecture
+
+The following components have been updated:
+
+- **Legacy**: Global `useAuth.ts` composable → **Current**: `useAuthService.ts` with dependency injection
+- **Legacy**: Direct service imports → **Current**: Dependency injection pattern
+- **Legacy**: Dual authentication detection → **Current**: Single source of truth via AuthService
 - `IdentityDialog.vue` → `LoginDialog.vue`
 - `PasswordDialog.vue` → Integrated into `LoginDialog.vue`
 - Nostr connection status → User authentication status