diff --git a/src/components/auth/ProfileDialog.vue b/src/components/auth/ProfileDialog.vue
index da30ad1..e84a821 100644
--- a/src/components/auth/ProfileDialog.vue
+++ b/src/components/auth/ProfileDialog.vue
@@ -5,9 +5,10 @@ import { Button } from '@/components/ui/button'
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card'
 import { Badge } from '@/components/ui/badge'
 import { LogoutConfirmDialog } from '@/components/ui/LogoutConfirmDialog'
-import { User, LogOut, Settings, Key, Wallet, ExternalLink } from 'lucide-vue-next'
+import { User, LogOut, Settings, Key, Wallet, ExternalLink, ArrowLeft } from 'lucide-vue-next'
 import { auth } from '@/composables/useAuthService'
 import { toast } from 'vue-sonner'
+import { ProfileSettings } from '@/modules/base'
 
 interface Props {
   isOpen: boolean
@@ -22,6 +23,7 @@ const emit = defineEmits<Emits>()
 
 const userDisplay = computed(() => auth.userDisplay.value)
 const showLogoutConfirm = ref(false)
+const showSettings = ref(false)
 
 // Get the API base URL from environment variables
 const apiBaseUrl = import.meta.env.VITE_LNBITS_BASE_URL || ''
@@ -44,24 +46,46 @@ function handleOpenWallet() {
 }
 
 function handleClose() {
+  showSettings.value = false
   emit('update:isOpen', false)
 }
+
+function toggleSettings() {
+  showSettings.value = !showSettings.value
+}
 </script>
 
 <template>
   <Dialog :open="isOpen" @update:open="handleClose">
-    <DialogContent class="sm:max-w-[500px]">
+    <DialogContent class="sm:max-w-[600px] max-h-[90vh] overflow-y-auto">
       <DialogHeader>
         <DialogTitle class="flex items-center gap-2">
+          <Button
+            v-if="showSettings"
+            variant="ghost"
+            size="icon"
+            class="h-8 w-8 -ml-2"
+            @click="toggleSettings"
+          >
+            <ArrowLeft class="w-4 h-4" />
+          </Button>
           <User class="w-5 h-5" />
-          User Profile
+          <span v-if="showSettings">Edit Profile</span>
+          <span v-else>User Profile</span>
         </DialogTitle>
         <DialogDescription>
-          Your account information and settings
+          <span v-if="showSettings">Update your profile information and Nostr identity</span>
+          <span v-else>Your account information and settings</span>
         </DialogDescription>
       </DialogHeader>
 
-      <div v-if="userDisplay" class="space-y-6">
+      <!-- Profile Settings View -->
+      <div v-if="showSettings">
+        <ProfileSettings />
+      </div>
+
+      <!-- Profile Info View -->
+      <div v-else-if="userDisplay" class="space-y-6">
         <!-- User Info Card -->
         <Card>
           <CardHeader>
@@ -116,10 +140,10 @@ function handleClose() {
                 Open Wallet
                 <ExternalLink class="w-3 h-3 ml-auto" />
               </Button>
-              
-              <Button variant="outline" class="w-full justify-start gap-2">
+
+              <Button variant="outline" @click="toggleSettings" class="w-full justify-start gap-2">
                 <Settings class="w-4 h-4" />
-                Account Settings
+                Edit Profile
               </Button>
               
               <Button variant="outline" class="w-full justify-start gap-2">
diff --git a/src/core/di-container.ts b/src/core/di-container.ts
index ac2f573..32221f5 100644
--- a/src/core/di-container.ts
+++ b/src/core/di-container.ts
@@ -137,6 +137,9 @@ export const SERVICE_TOKENS = {
   PROFILE_SERVICE: Symbol('profileService'),
   REACTION_SERVICE: Symbol('reactionService'),
 
+  // Nostr metadata services
+  NOSTR_METADATA_SERVICE: Symbol('nostrMetadataService'),
+
   // Events services
   EVENTS_SERVICE: Symbol('eventsService'),
   
diff --git a/src/modules/base/auth/auth-service.ts b/src/modules/base/auth/auth-service.ts
index 1c89f0e..9f64931 100644
--- a/src/modules/base/auth/auth-service.ts
+++ b/src/modules/base/auth/auth-service.ts
@@ -2,7 +2,9 @@
 import { ref, computed } from 'vue'
 import { BaseService } from '@/core/base/BaseService'
 import { eventBus } from '@/core/event-bus'
+import { injectService, SERVICE_TOKENS } from '@/core/di-container'
 import type { LoginCredentials, RegisterData, User } from '@/lib/api/lnbits'
+import type { NostrMetadataService } from '../nostr/nostr-metadata-service'
 
 export class AuthService extends BaseService {
   // Service metadata
@@ -79,16 +81,19 @@ export class AuthService extends BaseService {
 
   async login(credentials: LoginCredentials): Promise<void> {
     this.isLoading.value = true
-    
+
     try {
       await this.lnbitsAPI.login(credentials)
       const userData = await this.lnbitsAPI.getCurrentUser()
-      
+
       this.user.value = userData
       this.isAuthenticated.value = true
-      
+
       eventBus.emit('auth:login', { user: userData }, 'auth-service')
-      
+
+      // Auto-broadcast Nostr metadata on login
+      this.broadcastNostrMetadata()
+
     } catch (error) {
       const err = this.handleError(error, 'login')
       eventBus.emit('auth:login-failed', { error: err }, 'auth-service')
@@ -100,16 +105,19 @@ export class AuthService extends BaseService {
 
   async register(data: RegisterData): Promise<void> {
     this.isLoading.value = true
-    
+
     try {
       await this.lnbitsAPI.register(data)
       const userData = await this.lnbitsAPI.getCurrentUser()
-      
+
       this.user.value = userData
       this.isAuthenticated.value = true
-      
+
       eventBus.emit('auth:login', { user: userData }, 'auth-service')
-      
+
+      // Auto-broadcast Nostr metadata on registration
+      this.broadcastNostrMetadata()
+
     } catch (error) {
       const err = this.handleError(error, 'register')
       eventBus.emit('auth:login-failed', { error: err }, 'auth-service')
@@ -156,7 +164,19 @@ export class AuthService extends BaseService {
     try {
       this.isLoading.value = true
       const updatedUser = await this.lnbitsAPI.updateProfile(data)
-      this.user.value = updatedUser
+
+      // Preserve prvkey and pubkey from existing user since /auth/update doesn't return them
+      this.user.value = {
+        ...updatedUser,
+        pubkey: this.user.value?.pubkey || updatedUser.pubkey,
+        prvkey: this.user.value?.prvkey || updatedUser.prvkey
+      }
+
+      // Auto-broadcast Nostr metadata when profile is updated
+      // Note: ProfileSettings component will also manually broadcast,
+      // but this ensures metadata stays in sync even if updated elsewhere
+      this.broadcastNostrMetadata()
+
     } catch (error) {
       const err = this.handleError(error, 'updateProfile')
       throw err
@@ -165,6 +185,26 @@ export class AuthService extends BaseService {
     }
   }
 
+  /**
+   * Broadcast user metadata to Nostr relays (NIP-01 kind 0)
+   * Called automatically on login, registration, and profile updates
+   */
+  private async broadcastNostrMetadata(): Promise<void> {
+    try {
+      const metadataService = injectService<NostrMetadataService>(SERVICE_TOKENS.NOSTR_METADATA_SERVICE)
+      if (metadataService && this.user.value?.pubkey) {
+        // Broadcast in background - don't block login/update
+        metadataService.publishMetadata().catch(error => {
+          console.warn('Failed to broadcast Nostr metadata:', error)
+          // Don't throw - this is a non-critical background operation
+        })
+      }
+    } catch (error) {
+      // If service isn't available yet, silently skip
+      console.debug('Nostr metadata service not yet available')
+    }
+  }
+
   /**
    * Cleanup when service is disposed
    */
diff --git a/src/modules/base/components/ProfileSettings.vue b/src/modules/base/components/ProfileSettings.vue
new file mode 100644
index 0000000..d1dab22
--- /dev/null
+++ b/src/modules/base/components/ProfileSettings.vue
@@ -0,0 +1,325 @@
+<template>
+  <div class="space-y-6">
+    <div>
+      <h3 class="text-lg font-medium">Profile Settings</h3>
+      <p class="text-sm text-muted-foreground">
+        Manage your profile information and Nostr identity
+      </p>
+    </div>
+
+    <Separator />
+
+    <form @submit="onSubmit" class="space-y-6">
+      <!-- Profile Picture -->
+      <FormField name="picture">
+        <FormItem>
+          <FormLabel>Profile Picture</FormLabel>
+          <FormDescription>
+            Upload a profile picture. This will be published to your Nostr profile.
+          </FormDescription>
+          <div class="flex items-center gap-4">
+            <!-- Current picture preview -->
+            <div v-if="currentPictureUrl" class="relative">
+              <img
+                :src="currentPictureUrl"
+                alt="Profile picture"
+                class="h-20 w-20 rounded-full object-cover border-2 border-border"
+              />
+            </div>
+            <div v-else class="h-20 w-20 rounded-full bg-muted flex items-center justify-center border-2 border-border">
+              <User class="h-10 w-10 text-muted-foreground" />
+            </div>
+
+            <!-- Upload component -->
+            <ImageUpload
+              v-model="uploadedPicture"
+              :multiple="false"
+              :max-files="1"
+              :max-size-mb="5"
+              :disabled="isUpdating"
+              :allow-camera="true"
+              placeholder="Upload picture"
+              accept="image/*"
+            />
+          </div>
+          <FormMessage />
+        </FormItem>
+      </FormField>
+
+      <!-- Username (Read-only for now) -->
+      <!-- TODO: Enable username editing in the future
+           Note: Changing username would require updating:
+           - LNURLp extension: Lightning address (lnurlp)
+           - Nostr extension: NIP-05 identifier
+           This needs to be coordinated across multiple LNbits extensions
+      -->
+      <FormField v-slot="{ componentField }" name="username">
+        <FormItem>
+          <FormLabel>Username</FormLabel>
+          <FormControl>
+            <Input
+              placeholder="Enter username"
+              :disabled="true"
+              v-bind="componentField"
+            />
+          </FormControl>
+          <FormDescription>
+            Your unique username. This is used for your NIP-05 identifier ({{ nip05Preview }}) and Lightning Address. Username changes are not currently supported.
+          </FormDescription>
+          <FormMessage />
+        </FormItem>
+      </FormField>
+
+      <!-- Display Name (optional) -->
+      <FormField v-slot="{ componentField }" name="display_name">
+        <FormItem>
+          <FormLabel>Display Name (optional)</FormLabel>
+          <FormControl>
+            <Input
+              placeholder="Enter display name"
+              :disabled="isUpdating"
+              v-bind="componentField"
+            />
+          </FormControl>
+          <FormDescription>
+            A friendly display name shown on your profile
+          </FormDescription>
+          <FormMessage />
+        </FormItem>
+      </FormField>
+
+      <!-- Lightning Address / NIP-05 (read-only info) -->
+      <div class="rounded-lg border p-4 space-y-2 bg-muted/50">
+        <h4 class="text-sm font-medium">Nostr Identity</h4>
+        <div class="space-y-1 text-sm">
+          <div class="flex items-center gap-2">
+            <Zap class="h-4 w-4 text-yellow-500" />
+            <span class="text-muted-foreground">Lightning Address:</span>
+            <code class="text-xs bg-background px-2 py-1 rounded">{{ lightningAddress }}</code>
+          </div>
+          <div class="flex items-center gap-2">
+            <Hash class="h-4 w-4 text-purple-500" />
+            <span class="text-muted-foreground">NIP-05:</span>
+            <code class="text-xs bg-background px-2 py-1 rounded">{{ nip05Preview }}</code>
+          </div>
+        </div>
+        <p class="text-xs text-muted-foreground mt-2">
+          These identifiers are automatically derived from your username
+        </p>
+      </div>
+
+      <!-- Error Display -->
+      <div v-if="updateError" class="text-sm text-destructive">
+        {{ updateError }}
+      </div>
+
+      <!-- Success Display -->
+      <div v-if="updateSuccess" class="text-sm text-green-600">
+        Profile updated successfully!
+      </div>
+
+      <!-- Action Buttons -->
+      <div class="flex flex-col sm:flex-row gap-3">
+        <Button
+          type="submit"
+          :disabled="isUpdating || !isFormValid"
+          class="flex-1"
+        >
+          <span v-if="isUpdating">Updating...</span>
+          <span v-else>Update Profile</span>
+        </Button>
+
+        <Button
+          type="button"
+          variant="outline"
+          :disabled="isBroadcasting"
+          @click="broadcastMetadata"
+          class="flex-1"
+        >
+          <Radio class="mr-2 h-4 w-4" :class="{ 'animate-pulse': isBroadcasting }" />
+          <span v-if="isBroadcasting">Broadcasting...</span>
+          <span v-else>Broadcast to Nostr</span>
+        </Button>
+      </div>
+
+      <p class="text-xs text-muted-foreground">
+        Your profile is automatically broadcast to Nostr when you update it or log in.
+        Use the "Broadcast to Nostr" button to manually re-broadcast your profile.
+      </p>
+    </form>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref, computed, watch } from 'vue'
+import { useForm } from 'vee-validate'
+import { toTypedSchema } from '@vee-validate/zod'
+import * as z from 'zod'
+import { Button } from '@/components/ui/button'
+import { Input } from '@/components/ui/input'
+import { Separator } from '@/components/ui/separator'
+import { User, Zap, Hash, Radio } from 'lucide-vue-next'
+import {
+  FormControl,
+  FormDescription,
+  FormField,
+  FormItem,
+  FormLabel,
+  FormMessage,
+} from '@/components/ui/form'
+import ImageUpload from './ImageUpload.vue'
+import { useAuth } from '@/composables/useAuthService'
+import { injectService, SERVICE_TOKENS } from '@/core/di-container'
+import type { ImageUploadService } from '../services/ImageUploadService'
+import type { NostrMetadataService } from '../nostr/nostr-metadata-service'
+import { useToast } from '@/core/composables/useToast'
+
+// Services
+const { user, updateProfile } = useAuth()
+const imageService = injectService<ImageUploadService>(SERVICE_TOKENS.IMAGE_UPLOAD_SERVICE)
+const metadataService = injectService<NostrMetadataService>(SERVICE_TOKENS.NOSTR_METADATA_SERVICE)
+const toast = useToast()
+
+// Local state
+const isUpdating = ref(false)
+const isBroadcasting = ref(false)
+const updateError = ref<string | null>(null)
+const updateSuccess = ref(false)
+const uploadedPicture = ref<any[]>([])
+
+// Get current user data
+const currentUsername = computed(() => user.value?.username || '')
+const currentDisplayName = computed(() => user.value?.extra?.display_name || '')
+const currentPictureUrl = computed(() => user.value?.extra?.picture || '')
+
+// Lightning domain
+const lightningDomain = computed(() =>
+  import.meta.env.VITE_LIGHTNING_DOMAIN || window.location.hostname
+)
+
+// Computed previews
+const nip05Preview = computed(() => {
+  const username = form.values.username || currentUsername.value || 'username'
+  return `${username}@${lightningDomain.value}`
+})
+
+const lightningAddress = computed(() => nip05Preview.value)
+
+// Form schema
+const profileFormSchema = toTypedSchema(z.object({
+  username: z.string()
+    .min(3, "Username must be at least 3 characters")
+    .max(30, "Username must be less than 30 characters")
+    .regex(/^[a-z0-9_-]+$/i, "Username can only contain letters, numbers, hyphens, and underscores"),
+  display_name: z.string()
+    .max(50, "Display name must be less than 50 characters")
+    .optional(),
+  picture: z.string().url("Invalid picture URL").optional().or(z.literal(''))
+}))
+
+// Form setup
+const form = useForm({
+  validationSchema: profileFormSchema,
+  initialValues: {
+    username: currentUsername.value,
+    display_name: currentDisplayName.value,
+    picture: currentPictureUrl.value
+  }
+})
+
+// Watch for user changes and reset form
+watch(user, (newUser) => {
+  if (newUser) {
+    form.resetForm({
+      values: {
+        username: newUser.username || '',
+        display_name: newUser.extra?.display_name || '',
+        picture: newUser.extra?.picture || ''
+      }
+    })
+  }
+}, { immediate: true })
+
+const { meta } = form
+const isFormValid = computed(() => meta.value.valid)
+
+// Form submit handler
+const onSubmit = form.handleSubmit(async (values) => {
+  await updateUserProfile(values)
+})
+
+// Update user profile
+const updateUserProfile = async (formData: any) => {
+  isUpdating.value = true
+  updateError.value = null
+  updateSuccess.value = false
+
+  try {
+    // Get uploaded picture URL if a new picture was uploaded
+    let pictureUrl = formData.picture || currentPictureUrl.value
+
+    if (uploadedPicture.value && uploadedPicture.value.length > 0) {
+      const img = uploadedPicture.value[0]
+      if (img.alias) {
+        const imageUrl = imageService.getImageUrl(img.alias)
+        if (imageUrl) {
+          pictureUrl = imageUrl
+        }
+      }
+    }
+
+    // Prepare update data
+    const updateData = {
+      user_id: user.value?.id,
+      username: formData.username,
+      extra: {
+        display_name: formData.display_name || '',
+        picture: pictureUrl || ''
+      }
+    }
+
+    // Update profile via AuthService (which updates LNbits)
+    await updateProfile(updateData)
+
+    // Broadcast to Nostr automatically
+    try {
+      await metadataService.publishMetadata()
+      toast.success('Profile updated and broadcast to Nostr!')
+    } catch (nostrError) {
+      console.error('Failed to broadcast to Nostr:', nostrError)
+      toast.warning('Profile updated, but failed to broadcast to Nostr')
+    }
+
+    updateSuccess.value = true
+
+    // Clear success message after 3 seconds
+    setTimeout(() => {
+      updateSuccess.value = false
+    }, 3000)
+
+  } catch (error) {
+    const errorMessage = error instanceof Error ? error.message : 'Failed to update profile'
+    console.error('Error updating profile:', error)
+    updateError.value = errorMessage
+    toast.error(`Failed to update profile: ${errorMessage}`)
+  } finally {
+    isUpdating.value = false
+  }
+}
+
+// Manually broadcast metadata to Nostr
+const broadcastMetadata = async () => {
+  isBroadcasting.value = true
+
+  try {
+    const result = await metadataService.publishMetadata()
+    toast.success(`Profile broadcast to ${result.success}/${result.total} relays!`)
+  } catch (error) {
+    const errorMessage = error instanceof Error ? error.message : 'Failed to broadcast metadata'
+    console.error('Error broadcasting metadata:', error)
+    toast.error(`Failed to broadcast: ${errorMessage}`)
+  } finally {
+    isBroadcasting.value = false
+  }
+}
+</script>
diff --git a/src/modules/base/composables/useNostrMetadata.ts b/src/modules/base/composables/useNostrMetadata.ts
new file mode 100644
index 0000000..dac17a4
--- /dev/null
+++ b/src/modules/base/composables/useNostrMetadata.ts
@@ -0,0 +1,39 @@
+import { injectService, SERVICE_TOKENS } from '@/core/di-container'
+import type { NostrMetadataService, NostrMetadata } from '../nostr/nostr-metadata-service'
+
+/**
+ * Composable for accessing Nostr metadata service
+ *
+ * @example
+ * ```ts
+ * const { publishMetadata, getMetadata } = useNostrMetadata()
+ *
+ * // Get current metadata
+ * const metadata = getMetadata()
+ *
+ * // Publish metadata to Nostr relays
+ * await publishMetadata()
+ * ```
+ */
+export function useNostrMetadata() {
+  const metadataService = injectService<NostrMetadataService>(SERVICE_TOKENS.NOSTR_METADATA_SERVICE)
+
+  /**
+   * Publish user metadata to Nostr relays (NIP-01 kind 0)
+   */
+  const publishMetadata = async (): Promise<{ success: number; total: number }> => {
+    return await metadataService.publishMetadata()
+  }
+
+  /**
+   * Get current user's Nostr metadata
+   */
+  const getMetadata = (): NostrMetadata => {
+    return metadataService.getMetadata()
+  }
+
+  return {
+    publishMetadata,
+    getMetadata
+  }
+}
diff --git a/src/modules/base/index.ts b/src/modules/base/index.ts
index 640482f..d70a81f 100644
--- a/src/modules/base/index.ts
+++ b/src/modules/base/index.ts
@@ -2,6 +2,7 @@ import type { App } from 'vue'
 import type { ModulePlugin } from '@/core/types'
 import { container, SERVICE_TOKENS } from '@/core/di-container'
 import { relayHub } from './nostr/relay-hub'
+import { NostrMetadataService } from './nostr/nostr-metadata-service'
 
 // Import auth services
 import { auth } from './auth/auth-service'
@@ -20,11 +21,13 @@ import { ImageUploadService } from './services/ImageUploadService'
 
 // Import components
 import ImageUpload from './components/ImageUpload.vue'
+import ProfileSettings from './components/ProfileSettings.vue'
 
 // Create service instances
 const invoiceService = new InvoiceService()
 const lnbitsAPI = new LnbitsAPI()
 const imageUploadService = new ImageUploadService()
+const nostrMetadataService = new NostrMetadataService()
 
 /**
  * Base Module Plugin
@@ -39,7 +42,8 @@ export const baseModule: ModulePlugin = {
 
     // Register core Nostr services
     container.provide(SERVICE_TOKENS.RELAY_HUB, relayHub)
-    
+    container.provide(SERVICE_TOKENS.NOSTR_METADATA_SERVICE, nostrMetadataService)
+
     // Register auth service
     container.provide(SERVICE_TOKENS.AUTH_SERVICE, auth)
     
@@ -98,6 +102,10 @@ export const baseModule: ModulePlugin = {
       waitForDependencies: true, // ImageUploadService depends on ToastService
       maxRetries: 3
     })
+    await nostrMetadataService.initialize({
+      waitForDependencies: true, // NostrMetadataService depends on AuthService and RelayHub
+      maxRetries: 3
+    })
     // InvoiceService doesn't need initialization as it's not a BaseService
     
     console.log('✅ Base module installed successfully')
@@ -114,13 +122,15 @@ export const baseModule: ModulePlugin = {
     await storageService.dispose()
     await toastService.dispose()
     await imageUploadService.dispose()
+    await nostrMetadataService.dispose()
     // InvoiceService doesn't need disposal as it's not a BaseService
     await lnbitsAPI.dispose()
-    
+
     // Remove services from DI container
     container.remove(SERVICE_TOKENS.LNBITS_API)
     container.remove(SERVICE_TOKENS.INVOICE_SERVICE)
     container.remove(SERVICE_TOKENS.IMAGE_UPLOAD_SERVICE)
+    container.remove(SERVICE_TOKENS.NOSTR_METADATA_SERVICE)
     
     console.log('✅ Base module uninstalled')
   },
@@ -134,7 +144,8 @@ export const baseModule: ModulePlugin = {
     toastService,
     invoiceService,
     pwaService,
-    imageUploadService
+    imageUploadService,
+    nostrMetadataService
   },
 
   // No routes - base module is pure infrastructure
@@ -142,8 +153,12 @@ export const baseModule: ModulePlugin = {
 
   // Export components for use by other modules
   components: {
-    ImageUpload
+    ImageUpload,
+    ProfileSettings
   }
 }
 
+// Export components as named exports for direct import
+export { ImageUpload, ProfileSettings }
+
 export default baseModule
\ No newline at end of file
diff --git a/src/modules/base/nostr/nostr-metadata-service.ts b/src/modules/base/nostr/nostr-metadata-service.ts
new file mode 100644
index 0000000..16e77f6
--- /dev/null
+++ b/src/modules/base/nostr/nostr-metadata-service.ts
@@ -0,0 +1,162 @@
+import { BaseService } from '@/core/base/BaseService'
+import { injectService, SERVICE_TOKENS } from '@/core/di-container'
+import { finalizeEvent, type EventTemplate } from 'nostr-tools'
+import type { AuthService } from '@/modules/base/auth/auth-service'
+import type { RelayHub } from '@/modules/base/nostr/relay-hub'
+
+/**
+ * Nostr User Metadata (NIP-01 kind 0)
+ * https://github.com/nostr-protocol/nips/blob/master/01.md
+ */
+export interface NostrMetadata {
+  name?: string              // Display name (from username)
+  display_name?: string      // Alternative display name
+  about?: string             // Bio/description
+  picture?: string           // Profile picture URL
+  banner?: string            // Profile banner URL
+  nip05?: string            // NIP-05 identifier (username@domain)
+  lud16?: string            // Lightning Address (same as nip05)
+  website?: string          // Personal website
+}
+
+/**
+ * Service for publishing and managing Nostr user metadata (NIP-01 kind 0)
+ *
+ * This service handles:
+ * - Publishing user profile metadata to Nostr relays
+ * - Syncing LNbits user data with Nostr profile
+ * - Auto-broadcasting metadata on login and profile updates
+ */
+export class NostrMetadataService extends BaseService {
+  protected readonly metadata = {
+    name: 'NostrMetadataService',
+    version: '1.0.0',
+    dependencies: ['AuthService', 'RelayHub']
+  }
+
+  protected authService: AuthService | null = null
+  protected relayHub: RelayHub | null = null
+
+  protected async onInitialize(): Promise<void> {
+    console.log('NostrMetadataService: Starting initialization...')
+
+    this.authService = injectService<AuthService>(SERVICE_TOKENS.AUTH_SERVICE)
+    this.relayHub = injectService<RelayHub>(SERVICE_TOKENS.RELAY_HUB)
+
+    if (!this.authService) {
+      throw new Error('AuthService not available')
+    }
+
+    if (!this.relayHub) {
+      throw new Error('RelayHub service not available')
+    }
+
+    console.log('NostrMetadataService: Initialization complete')
+  }
+
+  /**
+   * Build Nostr metadata from LNbits user data
+   */
+  private buildMetadata(): NostrMetadata {
+    const user = this.authService?.user.value
+    if (!user) {
+      throw new Error('No authenticated user')
+    }
+
+    const lightningDomain = import.meta.env.VITE_LIGHTNING_DOMAIN || window.location.hostname
+    const username = user.username || user.id.slice(0, 8)
+
+    const metadata: NostrMetadata = {
+      name: username,
+      nip05: `${username}@${lightningDomain}`,
+      lud16: `${username}@${lightningDomain}`
+    }
+
+    // Add optional fields from user.extra if they exist
+    if (user.extra?.display_name) {
+      metadata.display_name = user.extra.display_name
+    }
+
+    if (user.extra?.picture) {
+      metadata.picture = user.extra.picture
+    }
+
+    return metadata
+  }
+
+  /**
+   * Publish user metadata to Nostr relays (NIP-01 kind 0)
+   *
+   * This creates a replaceable event that updates the user's profile.
+   * Only the latest kind 0 event for a given pubkey is kept by relays.
+   */
+  async publishMetadata(): Promise<{ success: number; total: number }> {
+    if (!this.authService?.isAuthenticated.value) {
+      throw new Error('Must be authenticated to publish metadata')
+    }
+
+    if (!this.relayHub?.isConnected.value) {
+      throw new Error('Not connected to relays')
+    }
+
+    const user = this.authService.user.value
+    if (!user?.prvkey) {
+      throw new Error('User private key not available')
+    }
+
+    try {
+      const metadata = this.buildMetadata()
+
+      console.log('📤 Publishing Nostr metadata (kind 0):', metadata)
+
+      // Create kind 0 event (user metadata)
+      // Content is JSON-stringified metadata
+      const eventTemplate: EventTemplate = {
+        kind: 0,
+        content: JSON.stringify(metadata),
+        tags: [],
+        created_at: Math.floor(Date.now() / 1000)
+      }
+
+      // Sign the event
+      const privkeyBytes = this.hexToUint8Array(user.prvkey)
+      const signedEvent = finalizeEvent(eventTemplate, privkeyBytes)
+
+      console.log('✅ Metadata event signed:', signedEvent.id)
+      console.log('📋 Full signed event:', JSON.stringify(signedEvent, null, 2))
+
+      // Publish to all connected relays
+      const result = await this.relayHub.publishEvent(signedEvent)
+
+      console.log(`✅ Metadata published to ${result.success}/${result.total} relays`)
+
+      return result
+
+    } catch (error) {
+      console.error('Failed to publish metadata:', error)
+      throw error
+    }
+  }
+
+  /**
+   * Get current user's Nostr metadata
+   */
+  getMetadata(): NostrMetadata {
+    return this.buildMetadata()
+  }
+
+  /**
+   * Helper function to convert hex string to Uint8Array
+   */
+  private hexToUint8Array(hex: string): Uint8Array {
+    const bytes = new Uint8Array(hex.length / 2)
+    for (let i = 0; i < hex.length; i += 2) {
+      bytes[i / 2] = parseInt(hex.substr(i, 2), 16)
+    }
+    return bytes
+  }
+
+  protected async onDestroy(): Promise<void> {
+    // Cleanup if needed
+  }
+}