feat(extensions): add NIP-15 marketplace extension

Implements a Nostr-native marketplace extension for Lightning.Pub that is compatible with NIP-15 (Nostr Marketplace). Features: - Stall management (kind 30017 events) - Product listings (kind 30018 events) - Order processing via encrypted Nostr DMs or RPC - Multi-currency support with exchange rate caching - Inventory management with stock tracking - Customer relationship management - Lightning payment integration The extension leverages Lightning.Pub's existing Nostr infrastructure for a more elegant implementation than traditional HTTP-based approaches. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
feat(extensions): add getLnurlPayInfo to ExtensionContext
2026-03-04 15:21:57 -05:00 · 2026-03-04 15:21:57 -05:00 · 2026-03-04 15:21:57 -05:00 · 2026-03-04 15:21:57 -05:00 · 2026-03-04 15:21:57 -05:00 · 2026-03-04 15:21:57 -05:00
25 changed files with 5478 additions and 16 deletions
--- a/src/extensions/README.md
+++ b/src/extensions/README.md
@ -0,0 +1,731 @@
+# Lightning.Pub Extension System
+
+A modular extension system that allows third-party functionality to be added to Lightning.Pub without modifying core code.
+
+## Table of Contents
+
+- [Overview](#overview)
+- [Architecture](#architecture)
+- [Creating an Extension](#creating-an-extension)
+- [Extension Lifecycle](#extension-lifecycle)
+- [ExtensionContext API](#extensioncontext-api)
+- [Database Isolation](#database-isolation)
+- [RPC Methods](#rpc-methods)
+- [HTTP Routes](#http-routes)
+- [Event Handling](#event-handling)
+- [Configuration](#configuration)
+- [Examples](#examples)
+
+---
+
+## Overview
+
+The extension system provides:
+
+- **Modularity**: Extensions are self-contained modules with their own code and data
+- **Isolation**: Each extension gets its own SQLite database
+- **Integration**: Extensions can register RPC methods, handle events, and interact with Lightning.Pub's payment and Nostr systems
+- **Lifecycle Management**: Automatic discovery, loading, and graceful shutdown
+
+### Built-in Extensions
+
+| Extension | Description |
+|-----------|-------------|
+| `marketplace` | NIP-15 Nostr marketplace for selling products via Lightning |
+| `withdraw` | LNURL-withdraw (LUD-03) for vouchers, faucets, and gifts |
+
+---
+
+## Architecture
+
+```
+┌─────────────────────────────────────────────────────────────────┐
+│                        Lightning.Pub                             │
+├─────────────────────────────────────────────────────────────────┤
+│                      Extension Loader                            │
+│  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐              │
+│  │ Extension A │  │ Extension B │  │ Extension C │   ...        │
+│  │  ┌───────┐  │  │  ┌───────┐  │  │  ┌───────┐  │              │
+│  │  │Context│  │  │  │Context│  │  │  │Context│  │              │
+│  │  └───────┘  │  │  └───────┘  │  │  └───────┘  │              │
+│  │  ┌───────┐  │  │  ┌───────┐  │  │  ┌───────┐  │              │
+│  │  │  DB   │  │  │  │  DB   │  │  │  │  DB   │  │              │
+│  │  └───────┘  │  │  └───────┘  │  │  └───────┘  │              │
+│  └─────────────┘  └─────────────┘  └─────────────┘              │
+├─────────────────────────────────────────────────────────────────┤
+│  Payment Manager  │  Nostr Transport  │  Application Manager    │
+└─────────────────────────────────────────────────────────────────┘
+```
+
+### Key Components
+
+| Component | File | Description |
+|-----------|------|-------------|
+| `ExtensionLoader` | `loader.ts` | Discovers, loads, and manages extensions |
+| `ExtensionContext` | `context.ts` | Bridge between extensions and Lightning.Pub |
+| `ExtensionDatabase` | `database.ts` | Isolated SQLite database per extension |
+
+---
+
+## Creating an Extension
+
+### Directory Structure
+
+```
+src/extensions/
+└── my-extension/
+    ├── index.ts           # Main entry point (required)
+    ├── types.ts           # TypeScript interfaces
+    ├── migrations.ts      # Database migrations
+    └── managers/          # Business logic
+        └── myManager.ts
+```
+
+### Minimal Extension
+
+```typescript
+// src/extensions/my-extension/index.ts
+
+import { Extension, ExtensionInfo, ExtensionContext, ExtensionDatabase } from '../types.js'
+
+export default class MyExtension implements Extension {
+  readonly info: ExtensionInfo = {
+    id: 'my-extension',        // Must match directory name
+    name: 'My Extension',
+    version: '1.0.0',
+    description: 'Does something useful',
+    author: 'Your Name',
+    minPubVersion: '1.0.0'     // Minimum Lightning.Pub version
+  }
+
+  async initialize(ctx: ExtensionContext, db: ExtensionDatabase): Promise<void> {
+    // Run migrations
+    await db.execute(`
+      CREATE TABLE IF NOT EXISTS my_table (
+        id TEXT PRIMARY KEY,
+        data TEXT
+      )
+    `)
+
+    // Register RPC methods
+    ctx.registerMethod('my-extension.doSomething', async (req, appId) => {
+      return { result: 'done' }
+    })
+
+    ctx.log('info', 'Extension initialized')
+  }
+
+  async shutdown(): Promise<void> {
+    // Cleanup resources
+  }
+}
+```
+
+### Extension Interface
+
+```typescript
+interface Extension {
+  // Required: Extension metadata
+  readonly info: ExtensionInfo
+
+  // Required: Called once when extension is loaded
+  initialize(ctx: ExtensionContext, db: ExtensionDatabase): Promise<void>
+
+  // Optional: Called when Lightning.Pub shuts down
+  shutdown?(): Promise<void>
+
+  // Optional: Health check for monitoring
+  healthCheck?(): Promise<boolean>
+}
+
+interface ExtensionInfo {
+  id: string              // Unique identifier (lowercase, no spaces)
+  name: string            // Display name
+  version: string         // Semver version
+  description: string     // Short description
+  author: string          // Author name
+  minPubVersion?: string  // Minimum Lightning.Pub version
+  dependencies?: string[] // Other extension IDs required
+}
+```
+
+---
+
+## Extension Lifecycle
+
+```
+┌──────────────┐
+│   Discover   │  Scan extensions directory for index.ts files
+└──────┬───────┘
+       │
+       ▼
+┌──────────────┐
+│    Load      │  Import module, instantiate class
+└──────┬───────┘
+       │
+       ▼
+┌──────────────┐
+│  Initialize  │  Create database, call initialize()
+└──────┬───────┘
+       │
+       ▼
+┌──────────────┐
+│    Ready     │  Extension is active, handling requests
+└──────┬───────┘
+       │
+       ▼ (on shutdown)
+┌──────────────┐
+│   Shutdown   │  Call shutdown(), close database
+└──────────────┘
+```
+
+### States
+
+| State | Description |
+|-------|-------------|
+| `loading` | Extension is being loaded |
+| `ready` | Extension is active and healthy |
+| `error` | Initialization failed |
+| `stopped` | Extension has been shut down |
+
+---
+
+## ExtensionContext API
+
+The `ExtensionContext` is passed to your extension during initialization. It provides access to Lightning.Pub functionality.
+
+### Application Management
+
+```typescript
+// Get information about an application
+const app = await ctx.getApplication(applicationId)
+// Returns: { id, name, nostr_public, balance_sats } | null
+```
+
+### Payment Operations
+
+```typescript
+// Create a Lightning invoice
+const invoice = await ctx.createInvoice(amountSats, {
+  memo: 'Payment for service',
+  expiry: 3600,  // seconds
+  metadata: { order_id: '123' }  // Returned in payment callback
+})
+// Returns: { id, paymentRequest, paymentHash, expiry }
+
+// Pay a Lightning invoice
+const result = await ctx.payInvoice(applicationId, bolt11Invoice, maxFeeSats)
+// Returns: { paymentHash, feeSats }
+```
+
+### Nostr Operations
+
+```typescript
+// Send encrypted DM (NIP-44)
+const eventId = await ctx.sendEncryptedDM(applicationId, recipientPubkey, content)
+
+// Publish a Nostr event (signed by application's key)
+const eventId = await ctx.publishNostrEvent({
+  kind: 30017,
+  pubkey: appPubkey,
+  created_at: Math.floor(Date.now() / 1000),
+  tags: [['d', 'identifier']],
+  content: JSON.stringify(data)
+})
+```
+
+### RPC Method Registration
+
+```typescript
+// Register a method that can be called via RPC
+ctx.registerMethod('my-extension.methodName', async (request, applicationId, userPubkey?) => {
+  // request: The RPC request payload
+  // applicationId: The calling application's ID
+  // userPubkey: The user's Nostr pubkey (if authenticated)
+
+  return { result: 'success' }
+})
+```
+
+### Event Subscriptions
+
+```typescript
+// Subscribe to payment received events
+ctx.onPaymentReceived(async (payment) => {
+  // payment: { invoiceId, paymentHash, amountSats, metadata }
+
+  if (payment.metadata?.extension === 'my-extension') {
+    // Handle payment for this extension
+  }
+})
+
+// Subscribe to incoming Nostr events
+ctx.onNostrEvent(async (event, applicationId) => {
+  // event: { id, pubkey, kind, tags, content, created_at }
+  // applicationId: The application this event is for
+
+  if (event.kind === 4) {  // DM
+    // Handle incoming message
+  }
+})
+```
+
+### Logging
+
+```typescript
+ctx.log('debug', 'Detailed debugging info')
+ctx.log('info', 'Normal operation info')
+ctx.log('warn', 'Warning message')
+ctx.log('error', 'Error occurred', errorObject)
+```
+
+---
+
+## Database Isolation
+
+Each extension gets its own SQLite database file at:
+```
+{databaseDir}/{extension-id}.db
+```
+
+### Database Interface
+
+```typescript
+interface ExtensionDatabase {
+  // Execute write queries (INSERT, UPDATE, DELETE, CREATE)
+  execute(sql: string, params?: any[]): Promise<{ changes?: number; lastId?: number }>
+
+  // Execute read queries (SELECT)
+  query<T>(sql: string, params?: any[]): Promise<T[]>
+
+  // Run multiple statements in a transaction
+  transaction<T>(fn: () => Promise<T>): Promise<T>
+}
+```
+
+### Migration Pattern
+
+```typescript
+// migrations.ts
+
+export interface Migration {
+  version: number
+  name: string
+  up: (db: ExtensionDatabase) => Promise<void>
+}
+
+export const migrations: Migration[] = [
+  {
+    version: 1,
+    name: 'create_initial_tables',
+    up: async (db) => {
+      await db.execute(`
+        CREATE TABLE items (
+          id TEXT PRIMARY KEY,
+          name TEXT NOT NULL,
+          created_at INTEGER NOT NULL
+        )
+      `)
+    }
+  },
+  {
+    version: 2,
+    name: 'add_status_column',
+    up: async (db) => {
+      await db.execute(`ALTER TABLE items ADD COLUMN status TEXT DEFAULT 'active'`)
+    }
+  }
+]
+
+// Run migrations in initialize()
+export async function runMigrations(db: ExtensionDatabase): Promise<void> {
+  const result = await db.query<{ value: string }>(
+    `SELECT value FROM _extension_meta WHERE key = 'migration_version'`
+  ).catch(() => [])
+
+  const currentVersion = result.length > 0 ? parseInt(result[0].value, 10) : 0
+
+  for (const migration of migrations) {
+    if (migration.version > currentVersion) {
+      console.log(`Running migration ${migration.version}: ${migration.name}`)
+      await migration.up(db)
+      await db.execute(
+        `INSERT INTO _extension_meta (key, value) VALUES ('migration_version', ?)
+         ON CONFLICT(key) DO UPDATE SET value = excluded.value`,
+        [String(migration.version)]
+      )
+    }
+  }
+}
+```
+
+---
+
+## RPC Methods
+
+Extensions register RPC methods that can be called by clients.
+
+### Naming Convention
+
+Methods should be namespaced with the extension ID:
+```
+{extension-id}.{methodName}
+```
+
+Examples:
+- `marketplace.createStall`
+- `withdraw.createLink`
+
+### Method Handler Signature
+
+```typescript
+type RpcMethodHandler = (
+  request: any,           // The request payload
+  applicationId: string,  // The calling application
+  userPubkey?: string     // The authenticated user (if any)
+) => Promise<any>
+```
+
+### Example
+
+```typescript
+ctx.registerMethod('my-extension.createItem', async (req, appId, userPubkey) => {
+  // Validate request
+  if (!req.name) {
+    throw new Error('Name is required')
+  }
+
+  // Create item
+  const item = await this.manager.create(appId, req)
+
+  // Return response
+  return { item }
+})
+```
+
+---
+
+## HTTP Routes
+
+Some extensions need HTTP endpoints (e.g., LNURL protocol). Extensions can define routes that the main application mounts.
+
+### Defining Routes
+
+```typescript
+interface HttpRoute {
+  method: 'GET' | 'POST'
+  path: string
+  handler: (req: HttpRequest) => Promise<HttpResponse>
+}
+
+interface HttpRequest {
+  params: Record<string, string>   // URL path params
+  query: Record<string, string>    // Query string params
+  body?: any                       // POST body
+  headers: Record<string, string>
+}
+
+interface HttpResponse {
+  status: number
+  body: any
+  headers?: Record<string, string>
+}
+```
+
+### Example
+
+```typescript
+class MyExtension implements Extension {
+  getHttpRoutes(): HttpRoute[] {
+    return [
+      {
+        method: 'GET',
+        path: '/api/v1/my-extension/:id',
+        handler: async (req) => {
+          const item = await this.getItem(req.params.id)
+          return {
+            status: 200,
+            body: item,
+            headers: { 'Content-Type': 'application/json' }
+          }
+        }
+      }
+    ]
+  }
+}
+```
+
+---
+
+## Event Handling
+
+### Payment Callbacks
+
+When you create an invoice with metadata, you'll receive that metadata back in the payment callback:
+
+```typescript
+// Creating invoice with metadata
+const invoice = await ctx.createInvoice(1000, {
+  metadata: {
+    extension: 'my-extension',
+    order_id: 'order-123'
+  }
+})
+
+// Handling payment
+ctx.onPaymentReceived(async (payment) => {
+  if (payment.metadata?.extension === 'my-extension') {
+    const orderId = payment.metadata.order_id
+    await this.handlePayment(orderId, payment)
+  }
+})
+```
+
+### Nostr Events
+
+Subscribe to Nostr events for your application:
+
+```typescript
+ctx.onNostrEvent(async (event, applicationId) => {
+  // Filter by event kind
+  if (event.kind === 4) {  // Encrypted DM
+    await this.handleDirectMessage(event, applicationId)
+  }
+})
+```
+
+---
+
+## Configuration
+
+### Loader Configuration
+
+```typescript
+interface ExtensionLoaderConfig {
+  extensionsDir: string         // Directory containing extensions
+  databaseDir: string           // Directory for extension databases
+  enabledExtensions?: string[]  // Whitelist (if set, only these load)
+  disabledExtensions?: string[] // Blacklist
+}
+```
+
+### Usage
+
+```typescript
+import { createExtensionLoader } from './extensions'
+
+const loader = createExtensionLoader({
+  extensionsDir: './src/extensions',
+  databaseDir: './data/extensions',
+  disabledExtensions: ['experimental-ext']
+}, mainHandler)
+
+await loader.loadAll()
+
+// Call extension methods
+const result = await loader.callMethod(
+  'marketplace.createStall',
+  { name: 'My Shop', currency: 'sat', shipping_zones: [] },
+  applicationId,
+  userPubkey
+)
+
+// Dispatch events
+loader.dispatchPaymentReceived(paymentData)
+loader.dispatchNostrEvent(event, applicationId)
+
+// Shutdown
+await loader.shutdown()
+```
+
+---
+
+## Examples
+
+### Example: Simple Counter Extension
+
+```typescript
+// src/extensions/counter/index.ts
+
+import { Extension, ExtensionInfo, ExtensionContext, ExtensionDatabase } from '../types.js'
+
+export default class CounterExtension implements Extension {
+  readonly info: ExtensionInfo = {
+    id: 'counter',
+    name: 'Simple Counter',
+    version: '1.0.0',
+    description: 'A simple counter for each application',
+    author: 'Example'
+  }
+
+  private db!: ExtensionDatabase
+
+  async initialize(ctx: ExtensionContext, db: ExtensionDatabase): Promise<void> {
+    this.db = db
+
+    await db.execute(`
+      CREATE TABLE IF NOT EXISTS counters (
+        application_id TEXT PRIMARY KEY,
+        count INTEGER NOT NULL DEFAULT 0
+      )
+    `)
+
+    ctx.registerMethod('counter.increment', async (req, appId) => {
+      await db.execute(
+        `INSERT INTO counters (application_id, count) VALUES (?, 1)
+         ON CONFLICT(application_id) DO UPDATE SET count = count + 1`,
+        [appId]
+      )
+      const result = await db.query<{ count: number }>(
+        'SELECT count FROM counters WHERE application_id = ?',
+        [appId]
+      )
+      return { count: result[0]?.count || 0 }
+    })
+
+    ctx.registerMethod('counter.get', async (req, appId) => {
+      const result = await db.query<{ count: number }>(
+        'SELECT count FROM counters WHERE application_id = ?',
+        [appId]
+      )
+      return { count: result[0]?.count || 0 }
+    })
+
+    ctx.registerMethod('counter.reset', async (req, appId) => {
+      await db.execute(
+        'UPDATE counters SET count = 0 WHERE application_id = ?',
+        [appId]
+      )
+      return { count: 0 }
+    })
+  }
+}
+```
+
+### Example: Payment-Triggered Extension
+
+```typescript
+// src/extensions/donations/index.ts
+
+import { Extension, ExtensionContext, ExtensionDatabase } from '../types.js'
+
+export default class DonationsExtension implements Extension {
+  readonly info = {
+    id: 'donations',
+    name: 'Donations',
+    version: '1.0.0',
+    description: 'Accept donations with thank-you messages',
+    author: 'Example'
+  }
+
+  private db!: ExtensionDatabase
+  private ctx!: ExtensionContext
+
+  async initialize(ctx: ExtensionContext, db: ExtensionDatabase): Promise<void> {
+    this.db = db
+    this.ctx = ctx
+
+    await db.execute(`
+      CREATE TABLE IF NOT EXISTS donations (
+        id TEXT PRIMARY KEY,
+        application_id TEXT NOT NULL,
+        amount_sats INTEGER NOT NULL,
+        donor_pubkey TEXT,
+        message TEXT,
+        created_at INTEGER NOT NULL
+      )
+    `)
+
+    // Create donation invoice
+    ctx.registerMethod('donations.createInvoice', async (req, appId) => {
+      const invoice = await ctx.createInvoice(req.amount_sats, {
+        memo: req.message || 'Donation',
+        metadata: {
+          extension: 'donations',
+          donor_pubkey: req.donor_pubkey,
+          message: req.message
+        }
+      })
+      return { invoice: invoice.paymentRequest }
+    })
+
+    // Handle successful payments
+    ctx.onPaymentReceived(async (payment) => {
+      if (payment.metadata?.extension !== 'donations') return
+
+      // Record donation
+      await db.execute(
+        `INSERT INTO donations (id, application_id, amount_sats, donor_pubkey, message, created_at)
+         VALUES (?, ?, ?, ?, ?, ?)`,
+        [
+          payment.paymentHash,
+          payment.metadata.application_id,
+          payment.amountSats,
+          payment.metadata.donor_pubkey,
+          payment.metadata.message,
+          Math.floor(Date.now() / 1000)
+        ]
+      )
+
+      // Send thank-you DM if donor has pubkey
+      if (payment.metadata.donor_pubkey) {
+        await ctx.sendEncryptedDM(
+          payment.metadata.application_id,
+          payment.metadata.donor_pubkey,
+          `Thank you for your donation of ${payment.amountSats} sats!`
+        )
+      }
+    })
+
+    // List donations
+    ctx.registerMethod('donations.list', async (req, appId) => {
+      const donations = await db.query(
+        `SELECT * FROM donations WHERE application_id = ? ORDER BY created_at DESC LIMIT ?`,
+        [appId, req.limit || 50]
+      )
+      return { donations }
+    })
+  }
+}
+```
+
+---
+
+## Best Practices
+
+1. **Namespace your methods**: Always prefix RPC methods with your extension ID
+2. **Use migrations**: Never modify existing migration files; create new ones
+3. **Handle errors gracefully**: Throw descriptive errors, don't return error objects
+4. **Clean up in shutdown**: Close connections, cancel timers, etc.
+5. **Log appropriately**: Use debug for verbose info, error for failures
+6. **Validate inputs**: Check request parameters before processing
+7. **Use transactions**: For multi-step database operations
+8. **Document your API**: Include types and descriptions for RPC methods
+
+---
+
+## Troubleshooting
+
+### Extension not loading
+
+1. Check that directory name matches `info.id`
+2. Verify `index.ts` has a default export
+3. Check for TypeScript/import errors in logs
+
+### Database errors
+
+1. Check migration syntax
+2. Verify column types match queries
+3. Look for migration version conflicts
+
+### RPC method not found
+
+1. Verify method is registered in `initialize()`
+2. Check method name includes extension prefix
+3. Ensure extension status is `ready`
+
+### Payment callbacks not firing
+
+1. Verify `metadata.extension` matches your extension ID
+2. Check that `onPaymentReceived` is registered in `initialize()`
+3. Confirm invoice was created through the extension
--- a/src/extensions/context.ts
+++ b/src/extensions/context.ts
@ -0,0 +1,309 @@
+import {
+  ExtensionContext,
+  ExtensionDatabase,
+  ExtensionInfo,
+  ApplicationInfo,
+  CreateInvoiceOptions,
+  CreatedInvoice,
+  PaymentReceivedData,
+  NostrEvent,
+  UnsignedNostrEvent,
+  RpcMethodHandler,
+  LnurlPayInfo
+} from './types.js'
+
+/**
+ * Main Handler interface (from Lightning.Pub)
+ * This is a minimal interface - the actual MainHandler has more methods
+ */
+export interface MainHandlerInterface {
+  // Application management
+  applicationManager: {
+    getById(id: string): Promise<any>
+  }
+
+  // Payment operations
+  paymentManager: {
+    createInvoice(params: {
+      applicationId: string
+      amountSats: number
+      memo?: string
+      expiry?: number
+      metadata?: Record<string, any>
+    }): Promise<{
+      id: string
+      paymentRequest: string
+      paymentHash: string
+      expiry: number
+    }>
+
+    payInvoice(params: {
+      applicationId: string
+      paymentRequest: string
+      maxFeeSats?: number
+    }): Promise<{
+      paymentHash: string
+      feeSats: number
+    }>
+
+    /**
+     * Get LNURL-pay info for a user by their Nostr pubkey
+     * This enables Lightning Address (LUD-16) and zap (NIP-57) support
+     */
+    getLnurlPayInfoByPubkey(pubkeyHex: string, options?: {
+      metadata?: string
+      description?: string
+    }): Promise<LnurlPayInfo>
+  }
+
+  // Nostr operations
+  sendNostrEvent(event: any): Promise<string | null>
+  sendEncryptedDM(applicationId: string, recipientPubkey: string, content: string): Promise<string>
+}
+
+/**
+ * Callback registries for extension events
+ */
+interface CallbackRegistries {
+  paymentReceived: Array<(payment: PaymentReceivedData) => Promise<void>>
+  nostrEvent: Array<(event: NostrEvent, applicationId: string) => Promise<void>>
+}
+
+/**
+ * Registered RPC method
+ */
+interface RegisteredMethod {
+  extensionId: string
+  handler: RpcMethodHandler
+}
+
+/**
+ * Extension Context Implementation
+ *
+ * Provides the interface for extensions to interact with Lightning.Pub.
+ * Each extension gets its own context instance.
+ */
+export class ExtensionContextImpl implements ExtensionContext {
+  private callbacks: CallbackRegistries = {
+    paymentReceived: [],
+    nostrEvent: []
+  }
+
+  constructor(
+    private extensionInfo: ExtensionInfo,
+    private database: ExtensionDatabase,
+    private mainHandler: MainHandlerInterface,
+    private methodRegistry: Map<string, RegisteredMethod>
+  ) {}
+
+  /**
+   * Get information about an application
+   */
+  async getApplication(applicationId: string): Promise<ApplicationInfo | null> {
+    try {
+      const app = await this.mainHandler.applicationManager.getById(applicationId)
+      if (!app) return null
+
+      return {
+        id: app.id,
+        name: app.name,
+        nostr_public: app.nostr_public,
+        balance_sats: app.balance || 0
+      }
+    } catch (e) {
+      this.log('error', `Failed to get application ${applicationId}:`, e)
+      return null
+    }
+  }
+
+  /**
+   * Create a Lightning invoice
+   */
+  async createInvoice(amountSats: number, options: CreateInvoiceOptions = {}): Promise<CreatedInvoice> {
+    // Note: In practice, this needs an applicationId. Extensions typically
+    // get this from the RPC request context. For now, we'll need to handle
+    // this in the actual implementation.
+    throw new Error('createInvoice requires applicationId from request context')
+  }
+
+  /**
+   * Create invoice with explicit application ID
+   * This is the internal method used by extensions
+   */
+  async createInvoiceForApp(
+    applicationId: string,
+    amountSats: number,
+    options: CreateInvoiceOptions = {}
+  ): Promise<CreatedInvoice> {
+    const result = await this.mainHandler.paymentManager.createInvoice({
+      applicationId,
+      amountSats,
+      memo: options.memo,
+      expiry: options.expiry,
+      metadata: {
+        ...options.metadata,
+        extension: this.extensionInfo.id
+      }
+    })
+
+    return {
+      id: result.id,
+      paymentRequest: result.paymentRequest,
+      paymentHash: result.paymentHash,
+      expiry: result.expiry
+    }
+  }
+
+  /**
+   * Pay a Lightning invoice
+   */
+  async payInvoice(
+    applicationId: string,
+    paymentRequest: string,
+    maxFeeSats?: number
+  ): Promise<{ paymentHash: string; feeSats: number }> {
+    return this.mainHandler.paymentManager.payInvoice({
+      applicationId,
+      paymentRequest,
+      maxFeeSats
+    })
+  }
+
+  /**
+   * Send an encrypted DM via Nostr
+   */
+  async sendEncryptedDM(
+    applicationId: string,
+    recipientPubkey: string,
+    content: string
+  ): Promise<string> {
+    return this.mainHandler.sendEncryptedDM(applicationId, recipientPubkey, content)
+  }
+
+  /**
+   * Publish a Nostr event
+   */
+  async publishNostrEvent(event: UnsignedNostrEvent): Promise<string | null> {
+    return this.mainHandler.sendNostrEvent(event)
+  }
+
+  /**
+   * Get LNURL-pay info for a user by pubkey
+   * Enables Lightning Address and zap support
+   */
+  async getLnurlPayInfo(pubkeyHex: string, options?: {
+    metadata?: string
+    description?: string
+  }): Promise<LnurlPayInfo> {
+    return this.mainHandler.paymentManager.getLnurlPayInfoByPubkey(pubkeyHex, options)
+  }
+
+  /**
+   * Subscribe to payment received callbacks
+   */
+  onPaymentReceived(callback: (payment: PaymentReceivedData) => Promise<void>): void {
+    this.callbacks.paymentReceived.push(callback)
+  }
+
+  /**
+   * Subscribe to incoming Nostr events
+   */
+  onNostrEvent(callback: (event: NostrEvent, applicationId: string) => Promise<void>): void {
+    this.callbacks.nostrEvent.push(callback)
+  }
+
+  /**
+   * Register an RPC method
+   */
+  registerMethod(name: string, handler: RpcMethodHandler): void {
+    const fullName = name.startsWith(`${this.extensionInfo.id}.`)
+      ? name
+      : `${this.extensionInfo.id}.${name}`
+
+    if (this.methodRegistry.has(fullName)) {
+      throw new Error(`RPC method ${fullName} already registered`)
+    }
+
+    this.methodRegistry.set(fullName, {
+      extensionId: this.extensionInfo.id,
+      handler
+    })
+
+    this.log('debug', `Registered RPC method: ${fullName}`)
+  }
+
+  /**
+   * Get the extension's database
+   */
+  getDatabase(): ExtensionDatabase {
+    return this.database
+  }
+
+  /**
+   * Log a message
+   */
+  log(level: 'debug' | 'info' | 'warn' | 'error', message: string, ...args: any[]): void {
+    const prefix = `[Extension:${this.extensionInfo.id}]`
+    switch (level) {
+      case 'debug':
+        console.debug(prefix, message, ...args)
+        break
+      case 'info':
+        console.info(prefix, message, ...args)
+        break
+      case 'warn':
+        console.warn(prefix, message, ...args)
+        break
+      case 'error':
+        console.error(prefix, message, ...args)
+        break
+    }
+  }
+
+  // ===== Internal Methods (called by ExtensionLoader) =====
+
+  /**
+   * Dispatch payment received event to extension callbacks
+   */
+  async dispatchPaymentReceived(payment: PaymentReceivedData): Promise<void> {
+    for (const callback of this.callbacks.paymentReceived) {
+      try {
+        await callback(payment)
+      } catch (e) {
+        this.log('error', 'Error in payment callback:', e)
+      }
+    }
+  }
+
+  /**
+   * Dispatch Nostr event to extension callbacks
+   */
+  async dispatchNostrEvent(event: NostrEvent, applicationId: string): Promise<void> {
+    for (const callback of this.callbacks.nostrEvent) {
+      try {
+        await callback(event, applicationId)
+      } catch (e) {
+        this.log('error', 'Error in Nostr event callback:', e)
+      }
+    }
+  }
+
+  /**
+   * Get registered callbacks for external access
+   */
+  getCallbacks(): CallbackRegistries {
+    return this.callbacks
+  }
+}
+
+/**
+ * Create an extension context
+ */
+export function createExtensionContext(
+  extensionInfo: ExtensionInfo,
+  database: ExtensionDatabase,
+  mainHandler: MainHandlerInterface,
+  methodRegistry: Map<string, RegisteredMethod>
+): ExtensionContextImpl {
+  return new ExtensionContextImpl(extensionInfo, database, mainHandler, methodRegistry)
+}
--- a/src/extensions/database.ts
+++ b/src/extensions/database.ts
@ -0,0 +1,148 @@
+import Database from 'better-sqlite3'
+import path from 'path'
+import fs from 'fs'
+import { ExtensionDatabase } from './types.js'
+
+/**
+ * Extension Database Implementation
+ *
+ * Provides isolated SQLite database access for each extension.
+ * Uses better-sqlite3 for synchronous, high-performance access.
+ */
+export class ExtensionDatabaseImpl implements ExtensionDatabase {
+  private db: Database.Database
+  private extensionId: string
+
+  constructor(extensionId: string, databaseDir: string) {
+    this.extensionId = extensionId
+
+    // Ensure database directory exists
+    if (!fs.existsSync(databaseDir)) {
+      fs.mkdirSync(databaseDir, { recursive: true })
+    }
+
+    // Create database file for this extension
+    const dbPath = path.join(databaseDir, `${extensionId}.db`)
+    this.db = new Database(dbPath)
+
+    // Enable WAL mode for better concurrency
+    this.db.pragma('journal_mode = WAL')
+
+    // Enable foreign keys
+    this.db.pragma('foreign_keys = ON')
+
+    // Create metadata table for tracking migrations
+    this.db.exec(`
+      CREATE TABLE IF NOT EXISTS _extension_meta (
+        key TEXT PRIMARY KEY,
+        value TEXT NOT NULL
+      )
+    `)
+  }
+
+  /**
+   * Execute a write query (INSERT, UPDATE, DELETE, CREATE, etc.)
+   */
+  async execute(sql: string, params: any[] = []): Promise<{ changes?: number; lastId?: number }> {
+    try {
+      const stmt = this.db.prepare(sql)
+      const result = stmt.run(...params)
+
+      return {
+        changes: result.changes,
+        lastId: result.lastInsertRowid as number
+      }
+    } catch (e) {
+      console.error(`[Extension:${this.extensionId}] Database execute error:`, e)
+      throw e
+    }
+  }
+
+  /**
+   * Execute a read query (SELECT)
+   */
+  async query<T = any>(sql: string, params: any[] = []): Promise<T[]> {
+    try {
+      const stmt = this.db.prepare(sql)
+      return stmt.all(...params) as T[]
+    } catch (e) {
+      console.error(`[Extension:${this.extensionId}] Database query error:`, e)
+      throw e
+    }
+  }
+
+  /**
+   * Execute multiple statements in a transaction
+   */
+  async transaction<T>(fn: () => Promise<T>): Promise<T> {
+    const runTransaction = this.db.transaction(() => {
+      // Note: better-sqlite3 transactions are synchronous
+      // We wrap the async function but it executes synchronously
+      return fn()
+    })
+
+    return runTransaction() as T
+  }
+
+  /**
+   * Get a metadata value
+   */
+  async getMeta(key: string): Promise<string | null> {
+    const rows = await this.query<{ value: string }>(
+      'SELECT value FROM _extension_meta WHERE key = ?',
+      [key]
+    )
+    return rows.length > 0 ? rows[0].value : null
+  }
+
+  /**
+   * Set a metadata value
+   */
+  async setMeta(key: string, value: string): Promise<void> {
+    await this.execute(
+      `INSERT INTO _extension_meta (key, value) VALUES (?, ?)
+       ON CONFLICT(key) DO UPDATE SET value = excluded.value`,
+      [key, value]
+    )
+  }
+
+  /**
+   * Get current migration version
+   */
+  async getMigrationVersion(): Promise<number> {
+    const version = await this.getMeta('migration_version')
+    return version ? parseInt(version, 10) : 0
+  }
+
+  /**
+   * Set migration version
+   */
+  async setMigrationVersion(version: number): Promise<void> {
+    await this.setMeta('migration_version', String(version))
+  }
+
+  /**
+   * Close the database connection
+   */
+  close(): void {
+    this.db.close()
+  }
+
+  /**
+   * Get the underlying database for advanced operations
+   * (Use with caution - bypasses isolation)
+   */
+  getUnderlyingDb(): Database.Database {
+    return this.db
+  }
+}
+
+/**
+ * Create an extension database instance
+ */
+export function createExtensionDatabase(
+  extensionId: string,
+  databaseDir: string
+): ExtensionDatabaseImpl {
+  return new ExtensionDatabaseImpl(extensionId, databaseDir)
+}
--- a/src/extensions/index.ts
+++ b/src/extensions/index.ts
@ -0,0 +1,56 @@
+/**
+ * Lightning.Pub Extension System
+ *
+ * This module provides the extension infrastructure for Lightning.Pub.
+ * Extensions can add functionality like marketplaces, subscriptions,
+ * tipping, and more.
+ *
+ * Usage:
+ *
+ * ```typescript
+ * import { createExtensionLoader, ExtensionLoaderConfig } from './extensions'
+ *
+ * const config: ExtensionLoaderConfig = {
+ *   extensionsDir: './extensions',
+ *   databaseDir: './data/extensions'
+ * }
+ *
+ * const loader = createExtensionLoader(config, mainHandler)
+ * await loader.loadAll()
+ *
+ * // Call extension methods
+ * const result = await loader.callMethod(
+ *   'marketplace.createStall',
+ *   { name: 'My Shop', currency: 'sat', shipping_zones: [...] },
+ *   applicationId
+ * )
+ * ```
+ */
+
+// Export types
+export {
+  Extension,
+  ExtensionInfo,
+  ExtensionContext,
+  ExtensionDatabase,
+  ExtensionModule,
+  ExtensionConstructor,
+  LoadedExtension,
+  ExtensionLoaderConfig,
+  ApplicationInfo,
+  CreateInvoiceOptions,
+  CreatedInvoice,
+  PaymentReceivedData,
+  NostrEvent,
+  UnsignedNostrEvent,
+  RpcMethodHandler
+} from './types.js'
+
+// Export loader
+export { ExtensionLoader, createExtensionLoader } from './loader.js'
+
+// Export database utilities
+export { ExtensionDatabaseImpl, createExtensionDatabase } from './database.js'
+
+// Export context utilities
+export { ExtensionContextImpl, createExtensionContext, MainHandlerInterface } from './context.js'
--- a/src/extensions/loader.ts
+++ b/src/extensions/loader.ts
@ -0,0 +1,406 @@
+import path from 'path'
+import fs from 'fs'
+import {
+  Extension,
+  ExtensionInfo,
+  ExtensionModule,
+  LoadedExtension,
+  ExtensionLoaderConfig,
+  RpcMethodHandler,
+  PaymentReceivedData,
+  NostrEvent
+} from './types.js'
+import { ExtensionDatabaseImpl, createExtensionDatabase } from './database.js'
+import { ExtensionContextImpl, createExtensionContext, MainHandlerInterface } from './context.js'
+
+/**
+ * Registered RPC method entry
+ */
+interface RegisteredMethod {
+  extensionId: string
+  handler: RpcMethodHandler
+}
+
+/**
+ * Extension Loader
+ *
+ * Discovers, loads, and manages Lightning.Pub extensions.
+ * Provides lifecycle management and event dispatching.
+ */
+export class ExtensionLoader {
+  private config: ExtensionLoaderConfig
+  private mainHandler: MainHandlerInterface
+  private extensions: Map<string, LoadedExtension> = new Map()
+  private contexts: Map<string, ExtensionContextImpl> = new Map()
+  private methodRegistry: Map<string, RegisteredMethod> = new Map()
+  private initialized = false
+
+  constructor(config: ExtensionLoaderConfig, mainHandler: MainHandlerInterface) {
+    this.config = config
+    this.mainHandler = mainHandler
+  }
+
+  /**
+   * Discover and load all extensions
+   */
+  async loadAll(): Promise<void> {
+    if (this.initialized) {
+      throw new Error('Extension loader already initialized')
+    }
+
+    console.log('[Extensions] Loading extensions from:', this.config.extensionsDir)
+
+    // Ensure directories exist
+    if (!fs.existsSync(this.config.extensionsDir)) {
+      console.log('[Extensions] Extensions directory does not exist, creating...')
+      fs.mkdirSync(this.config.extensionsDir, { recursive: true })
+      this.initialized = true
+      return
+    }
+
+    if (!fs.existsSync(this.config.databaseDir)) {
+      fs.mkdirSync(this.config.databaseDir, { recursive: true })
+    }
+
+    // Discover extensions
+    const extensionDirs = await this.discoverExtensions()
+    console.log(`[Extensions] Found ${extensionDirs.length} extension(s)`)
+
+    // Load extensions in dependency order
+    const loadOrder = await this.resolveDependencies(extensionDirs)
+
+    for (const extDir of loadOrder) {
+      try {
+        await this.loadExtension(extDir)
+      } catch (e) {
+        console.error(`[Extensions] Failed to load extension from ${extDir}:`, e)
+      }
+    }
+
+    this.initialized = true
+    console.log(`[Extensions] Loaded ${this.extensions.size} extension(s)`)
+  }
+
+  /**
+   * Discover extension directories
+   */
+  private async discoverExtensions(): Promise<string[]> {
+    const entries = fs.readdirSync(this.config.extensionsDir, { withFileTypes: true })
+    const extensionDirs: string[] = []
+
+    for (const entry of entries) {
+      if (!entry.isDirectory()) continue
+
+      const extDir = path.join(this.config.extensionsDir, entry.name)
+      const indexPath = path.join(extDir, 'index.ts')
+      const indexJsPath = path.join(extDir, 'index.js')
+
+      // Check for index file
+      if (fs.existsSync(indexPath) || fs.existsSync(indexJsPath)) {
+        // Check enabled/disabled lists
+        if (this.config.disabledExtensions?.includes(entry.name)) {
+          console.log(`[Extensions] Skipping disabled extension: ${entry.name}`)
+          continue
+        }
+
+        if (this.config.enabledExtensions &&
+            !this.config.enabledExtensions.includes(entry.name)) {
+          console.log(`[Extensions] Skipping non-enabled extension: ${entry.name}`)
+          continue
+        }
+
+        extensionDirs.push(extDir)
+      }
+    }
+
+    return extensionDirs
+  }
+
+  /**
+   * Resolve extension dependencies and return load order
+   */
+  private async resolveDependencies(extensionDirs: string[]): Promise<string[]> {
+    // For now, simple alphabetical order
+    // TODO: Implement proper dependency resolution with topological sort
+    return extensionDirs.sort()
+  }
+
+  /**
+   * Load a single extension
+   */
+  private async loadExtension(extensionDir: string): Promise<void> {
+    const dirName = path.basename(extensionDir)
+    console.log(`[Extensions] Loading extension: ${dirName}`)
+
+    // Determine index file path
+    let indexPath = path.join(extensionDir, 'index.js')
+    if (!fs.existsSync(indexPath)) {
+      indexPath = path.join(extensionDir, 'index.ts')
+    }
+
+    // Dynamic import
+    const moduleUrl = `file://${indexPath}`
+    const module = await import(moduleUrl) as ExtensionModule
+
+    if (!module.default) {
+      throw new Error(`Extension ${dirName} has no default export`)
+    }
+
+    // Instantiate extension
+    const ExtensionClass = module.default
+    const instance = new ExtensionClass() as Extension
+
+    if (!instance.info) {
+      throw new Error(`Extension ${dirName} has no info property`)
+    }
+
+    const info = instance.info
+
+    // Validate extension ID matches directory name
+    if (info.id !== dirName) {
+      console.warn(
+        `[Extensions] Extension ID '${info.id}' doesn't match directory '${dirName}'`
+      )
+    }
+
+    // Check for duplicate
+    if (this.extensions.has(info.id)) {
+      throw new Error(`Extension ${info.id} already loaded`)
+    }
+
+    // Create isolated database
+    const database = createExtensionDatabase(info.id, this.config.databaseDir)
+
+    // Create context
+    const context = createExtensionContext(
+      info,
+      database,
+      this.mainHandler,
+      this.methodRegistry
+    )
+
+    // Track as loading
+    const loaded: LoadedExtension = {
+      info,
+      instance,
+      database,
+      status: 'loading',
+      loadedAt: Date.now()
+    }
+    this.extensions.set(info.id, loaded)
+    this.contexts.set(info.id, context)
+
+    try {
+      // Initialize extension
+      await instance.initialize(context, database)
+
+      loaded.status = 'ready'
+      console.log(`[Extensions] Extension ${info.id} v${info.version} loaded successfully`)
+    } catch (e) {
+      loaded.status = 'error'
+      loaded.error = e as Error
+      console.error(`[Extensions] Extension ${info.id} initialization failed:`, e)
+      throw e
+    }
+  }
+
+  /**
+   * Unload a specific extension
+   */
+  async unloadExtension(extensionId: string): Promise<void> {
+    const loaded = this.extensions.get(extensionId)
+    if (!loaded) {
+      throw new Error(`Extension ${extensionId} not found`)
+    }
+
+    console.log(`[Extensions] Unloading extension: ${extensionId}`)
+
+    try {
+      // Call shutdown if available
+      if (loaded.instance.shutdown) {
+        await loaded.instance.shutdown()
+      }
+
+      loaded.status = 'stopped'
+    } catch (e) {
+      console.error(`[Extensions] Error during ${extensionId} shutdown:`, e)
+    }
+
+    // Close database
+    if (loaded.database instanceof ExtensionDatabaseImpl) {
+      loaded.database.close()
+    }
+
+    // Remove registered methods
+    for (const [name, method] of this.methodRegistry.entries()) {
+      if (method.extensionId === extensionId) {
+        this.methodRegistry.delete(name)
+      }
+    }
+
+    // Remove from maps
+    this.extensions.delete(extensionId)
+    this.contexts.delete(extensionId)
+  }
+
+  /**
+   * Shutdown all extensions
+   */
+  async shutdown(): Promise<void> {
+    console.log('[Extensions] Shutting down all extensions...')
+
+    for (const extensionId of this.extensions.keys()) {
+      try {
+        await this.unloadExtension(extensionId)
+      } catch (e) {
+        console.error(`[Extensions] Error unloading ${extensionId}:`, e)
+      }
+    }
+
+    console.log('[Extensions] All extensions shut down')
+  }
+
+  /**
+   * Get a loaded extension
+   */
+  getExtension(extensionId: string): LoadedExtension | undefined {
+    return this.extensions.get(extensionId)
+  }
+
+  /**
+   * Get all loaded extensions
+   */
+  getAllExtensions(): LoadedExtension[] {
+    return Array.from(this.extensions.values())
+  }
+
+  /**
+   * Check if an extension is loaded and ready
+   */
+  isReady(extensionId: string): boolean {
+    const ext = this.extensions.get(extensionId)
+    return ext?.status === 'ready'
+  }
+
+  /**
+   * Get all registered RPC methods
+   */
+  getRegisteredMethods(): Map<string, RegisteredMethod> {
+    return this.methodRegistry
+  }
+
+  /**
+   * Call an extension RPC method
+   */
+  async callMethod(
+    methodName: string,
+    request: any,
+    applicationId: string,
+    userPubkey?: string
+  ): Promise<any> {
+    const method = this.methodRegistry.get(methodName)
+    if (!method) {
+      throw new Error(`Unknown method: ${methodName}`)
+    }
+
+    const ext = this.extensions.get(method.extensionId)
+    if (!ext || ext.status !== 'ready') {
+      throw new Error(`Extension ${method.extensionId} not ready`)
+    }
+
+    return method.handler(request, applicationId, userPubkey)
+  }
+
+  /**
+   * Check if a method exists
+   */
+  hasMethod(methodName: string): boolean {
+    return this.methodRegistry.has(methodName)
+  }
+
+  /**
+   * Dispatch payment received event to all extensions
+   */
+  async dispatchPaymentReceived(payment: PaymentReceivedData): Promise<void> {
+    for (const context of this.contexts.values()) {
+      try {
+        await context.dispatchPaymentReceived(payment)
+      } catch (e) {
+        console.error('[Extensions] Error dispatching payment:', e)
+      }
+    }
+  }
+
+  /**
+   * Dispatch Nostr event to all extensions
+   */
+  async dispatchNostrEvent(event: NostrEvent, applicationId: string): Promise<void> {
+    for (const context of this.contexts.values()) {
+      try {
+        await context.dispatchNostrEvent(event, applicationId)
+      } catch (e) {
+        console.error('[Extensions] Error dispatching Nostr event:', e)
+      }
+    }
+  }
+
+  /**
+   * Run health checks on all extensions
+   */
+  async healthCheck(): Promise<Map<string, boolean>> {
+    const results = new Map<string, boolean>()
+
+    for (const [id, ext] of this.extensions.entries()) {
+      if (ext.status !== 'ready') {
+        results.set(id, false)
+        continue
+      }
+
+      try {
+        if (ext.instance.healthCheck) {
+          results.set(id, await ext.instance.healthCheck())
+        } else {
+          results.set(id, true)
+        }
+      } catch (e) {
+        results.set(id, false)
+      }
+    }
+
+    return results
+  }
+
+  /**
+   * Get extension status summary
+   */
+  getStatus(): {
+    total: number
+    ready: number
+    error: number
+    extensions: Array<{ id: string; name: string; version: string; status: string }>
+  } {
+    const extensions = this.getAllExtensions().map(ext => ({
+      id: ext.info.id,
+      name: ext.info.name,
+      version: ext.info.version,
+      status: ext.status
+    }))
+
+    return {
+      total: extensions.length,
+      ready: extensions.filter(e => e.status === 'ready').length,
+      error: extensions.filter(e => e.status === 'error').length,
+      extensions
+    }
+  }
+}
+
+/**
+ * Create an extension loader instance
+ */
+export function createExtensionLoader(
+  config: ExtensionLoaderConfig,
+  mainHandler: MainHandlerInterface
+): ExtensionLoader {
+  return new ExtensionLoader(config, mainHandler)
+}
--- a/src/extensions/marketplace/index.ts
+++ b/src/extensions/marketplace/index.ts
@ -0,0 +1,390 @@
+import {
+  Extension, ExtensionContext, ExtensionDatabase, ExtensionInfo,
+  CreateStallRequest, UpdateStallRequest,
+  CreateProductRequest, UpdateProductRequest,
+  CreateOrderRequest
+} from './types.js'
+import { migrations } from './migrations.js'
+import { StallManager } from './managers/stallManager.js'
+import { ProductManager } from './managers/productManager.js'
+import { OrderManager } from './managers/orderManager.js'
+import { MessageManager } from './managers/messageManager.js'
+import { parseOrderRequest, parseMessageType, NostrEvent } from './nostr/parser.js'
+import { EVENT_KINDS } from './nostr/kinds.js'
+import { validatePubkey } from './utils/validation.js'
+
+/**
+ * Marketplace Extension for Lightning.Pub
+ *
+ * Implements NIP-15 compatible marketplace functionality:
+ * - Stall management (kind 30017 events)
+ * - Product listings (kind 30018 events)
+ * - Order processing via encrypted DMs
+ * - Customer relationship management
+ */
+export default class MarketplaceExtension implements Extension {
+  readonly info: ExtensionInfo = {
+    id: 'marketplace',
+    name: 'Nostr Marketplace',
+    version: '1.0.0',
+    description: 'NIP-15 compatible marketplace for selling products via Lightning',
+    author: 'Lightning.Pub',
+    minPubVersion: '1.0.0'
+  }
+
+  private stallManager!: StallManager
+  private productManager!: ProductManager
+  private orderManager!: OrderManager
+  private messageManager!: MessageManager
+
+  /**
+   * Initialize the extension
+   */
+  async initialize(ctx: ExtensionContext, db: ExtensionDatabase): Promise<void> {
+    // Run migrations
+    for (const migration of migrations) {
+      await migration.up(db)
+    }
+
+    // Initialize managers
+    this.stallManager = new StallManager(db, ctx)
+    this.productManager = new ProductManager(db, ctx)
+    this.orderManager = new OrderManager(db, ctx)
+    this.messageManager = new MessageManager(db, ctx)
+
+    // Register RPC methods
+    this.registerRpcMethods(ctx)
+
+    // Subscribe to payment callbacks
+    ctx.onPaymentReceived(async (payment) => {
+      if (payment.metadata?.extension === 'marketplace' && payment.metadata?.order_id) {
+        await this.orderManager.handlePayment(payment.invoiceId)
+      }
+    })
+
+    // Subscribe to incoming Nostr events
+    ctx.onNostrEvent(async (event, applicationId) => {
+      await this.handleNostrEvent(event, applicationId)
+    })
+
+    console.log(`[Marketplace] Extension initialized`)
+  }
+
+  /**
+   * Cleanup on shutdown
+   */
+  async shutdown(): Promise<void> {
+    console.log(`[Marketplace] Extension shutting down`)
+  }
+
+  /**
+   * Register all RPC methods with the extension context
+   */
+  private registerRpcMethods(ctx: ExtensionContext): void {
+    // ===== Stall Methods =====
+
+    ctx.registerMethod('marketplace.createStall', async (req, appId) => {
+      const stall = await this.stallManager.create(appId, req as CreateStallRequest)
+      return { stall }
+    })
+
+    ctx.registerMethod('marketplace.getStall', async (req, appId) => {
+      const stall = await this.stallManager.get(req.id, appId)
+      if (!stall) throw new Error('Stall not found')
+      return { stall }
+    })
+
+    ctx.registerMethod('marketplace.listStalls', async (_req, appId) => {
+      const stalls = await this.stallManager.list(appId)
+      return { stalls }
+    })
+
+    ctx.registerMethod('marketplace.updateStall', async (req, appId) => {
+      const stall = await this.stallManager.update(req.id, appId, req as UpdateStallRequest)
+      if (!stall) throw new Error('Stall not found')
+      return { stall }
+    })
+
+    ctx.registerMethod('marketplace.deleteStall', async (req, appId) => {
+      const success = await this.stallManager.delete(req.id, appId)
+      if (!success) throw new Error('Stall not found')
+      return { success }
+    })
+
+    ctx.registerMethod('marketplace.publishStall', async (req, appId) => {
+      const stall = await this.stallManager.get(req.id, appId)
+      if (!stall) throw new Error('Stall not found')
+      const eventId = await this.stallManager.publishToNostr(stall)
+      return { event_id: eventId }
+    })
+
+    // ===== Product Methods =====
+
+    ctx.registerMethod('marketplace.createProduct', async (req, appId) => {
+      const product = await this.productManager.create(
+        appId,
+        req.stall_id,
+        req as CreateProductRequest
+      )
+      return { product }
+    })
+
+    ctx.registerMethod('marketplace.getProduct', async (req, appId) => {
+      const product = await this.productManager.get(req.id, appId)
+      if (!product) throw new Error('Product not found')
+      return { product }
+    })
+
+    ctx.registerMethod('marketplace.listProducts', async (req, appId) => {
+      const products = await this.productManager.list(appId, {
+        stall_id: req.stall_id,
+        category: req.category,
+        active_only: req.active_only,
+        limit: req.limit,
+        offset: req.offset
+      })
+      return { products }
+    })
+
+    ctx.registerMethod('marketplace.updateProduct', async (req, appId) => {
+      const product = await this.productManager.update(req.id, appId, req as UpdateProductRequest)
+      if (!product) throw new Error('Product not found')
+      return { product }
+    })
+
+    ctx.registerMethod('marketplace.deleteProduct', async (req, appId) => {
+      const success = await this.productManager.delete(req.id, appId)
+      if (!success) throw new Error('Product not found')
+      return { success }
+    })
+
+    ctx.registerMethod('marketplace.updateInventory', async (req, appId) => {
+      const newQuantity = await this.productManager.updateQuantity(req.id, appId, req.delta)
+      return { quantity: newQuantity }
+    })
+
+    ctx.registerMethod('marketplace.checkStock', async (req, appId) => {
+      const result = await this.productManager.checkStock(req.items, appId)
+      return result
+    })
+
+    // ===== Order Methods =====
+
+    ctx.registerMethod('marketplace.createOrder', async (req, appId, userPubkey) => {
+      if (!userPubkey) throw new Error('User pubkey required')
+      const order = await this.orderManager.createFromRpc(
+        appId,
+        userPubkey,
+        req as CreateOrderRequest,
+        req.app_user_id
+      )
+      return { order }
+    })
+
+    ctx.registerMethod('marketplace.getOrder', async (req, appId) => {
+      const order = await this.orderManager.get(req.id, appId)
+      if (!order) throw new Error('Order not found')
+      return { order }
+    })
+
+    ctx.registerMethod('marketplace.listOrders', async (req, appId) => {
+      const orders = await this.orderManager.list(appId, {
+        stall_id: req.stall_id,
+        customer_pubkey: req.customer_pubkey,
+        status: req.status,
+        limit: req.limit,
+        offset: req.offset
+      })
+      return { orders }
+    })
+
+    ctx.registerMethod('marketplace.createInvoice', async (req, appId) => {
+      const order = await this.orderManager.createInvoice(req.order_id, appId)
+      return { order }
+    })
+
+    ctx.registerMethod('marketplace.updateOrderStatus', async (req, appId) => {
+      const order = await this.orderManager.updateStatus(
+        req.id,
+        appId,
+        req.status,
+        req.message
+      )
+      if (!order) throw new Error('Order not found')
+      return { order }
+    })
+
+    ctx.registerMethod('marketplace.sendPaymentRequest', async (req, appId) => {
+      const order = await this.orderManager.get(req.order_id, appId)
+      if (!order) throw new Error('Order not found')
+
+      // Create invoice if not exists
+      if (!order.invoice) {
+        await this.orderManager.createInvoice(req.order_id, appId)
+      }
+
+      const updatedOrder = await this.orderManager.get(req.order_id, appId)
+      if (!updatedOrder?.invoice) throw new Error('Failed to create invoice')
+
+      await this.orderManager.sendPaymentRequestDM(updatedOrder)
+      return { order: updatedOrder }
+    })
+
+    // ===== Message/Customer Methods =====
+
+    ctx.registerMethod('marketplace.listMessages', async (req, appId) => {
+      const messages = await this.messageManager.listMessages(appId, {
+        customer_pubkey: req.customer_pubkey,
+        order_id: req.order_id,
+        incoming_only: req.incoming_only,
+        unread_only: req.unread_only,
+        limit: req.limit,
+        offset: req.offset
+      })
+      return { messages }
+    })
+
+    ctx.registerMethod('marketplace.getConversation', async (req, appId) => {
+      if (!validatePubkey(req.customer_pubkey)) {
+        throw new Error('Invalid customer pubkey')
+      }
+      const messages = await this.messageManager.getConversation(
+        appId,
+        req.customer_pubkey,
+        req.limit
+      )
+      return { messages }
+    })
+
+    ctx.registerMethod('marketplace.sendMessage', async (req, appId) => {
+      if (!validatePubkey(req.customer_pubkey)) {
+        throw new Error('Invalid customer pubkey')
+      }
+      const message = await this.messageManager.sendMessage(
+        appId,
+        req.customer_pubkey,
+        req.message,
+        req.order_id
+      )
+      return { message }
+    })
+
+    ctx.registerMethod('marketplace.markMessagesRead', async (req, appId) => {
+      if (!validatePubkey(req.customer_pubkey)) {
+        throw new Error('Invalid customer pubkey')
+      }
+      const count = await this.messageManager.markAsRead(appId, req.customer_pubkey)
+      return { marked_read: count }
+    })
+
+    ctx.registerMethod('marketplace.getUnreadCount', async (_req, appId) => {
+      const count = await this.messageManager.getUnreadCount(appId)
+      return { unread_count: count }
+    })
+
+    ctx.registerMethod('marketplace.listCustomers', async (req, appId) => {
+      const customers = await this.messageManager.listCustomers(appId, {
+        has_orders: req.has_orders,
+        has_unread: req.has_unread,
+        limit: req.limit,
+        offset: req.offset
+      })
+      return { customers }
+    })
+
+    ctx.registerMethod('marketplace.getCustomer', async (req, appId) => {
+      if (!validatePubkey(req.pubkey)) {
+        throw new Error('Invalid customer pubkey')
+      }
+      const customer = await this.messageManager.getCustomer(req.pubkey, appId)
+      if (!customer) throw new Error('Customer not found')
+      return { customer }
+    })
+
+    ctx.registerMethod('marketplace.getCustomerStats', async (_req, appId) => {
+      const stats = await this.messageManager.getCustomerStats(appId)
+      return stats
+    })
+
+    // ===== Bulk Operations =====
+
+    ctx.registerMethod('marketplace.republishAll', async (req, appId) => {
+      let stallCount = 0
+      let productCount = 0
+
+      if (req.stall_id) {
+        // Republish specific stall and its products
+        const stall = await this.stallManager.get(req.stall_id, appId)
+        if (stall) {
+          await this.stallManager.publishToNostr(stall)
+          stallCount = 1
+          productCount = await this.productManager.republishAllForStall(req.stall_id, appId)
+        }
+      } else {
+        // Republish all
+        stallCount = await this.stallManager.republishAll(appId)
+        const stalls = await this.stallManager.list(appId)
+        for (const stall of stalls) {
+          productCount += await this.productManager.republishAllForStall(stall.id, appId)
+        }
+      }
+
+      return {
+        stalls_published: stallCount,
+        products_published: productCount
+      }
+    })
+  }
+
+  /**
+   * Handle incoming Nostr events (DMs for orders)
+   */
+  private async handleNostrEvent(event: NostrEvent, applicationId: string): Promise<void> {
+    // Only handle DMs for now
+    if (event.kind !== EVENT_KINDS.DIRECT_MESSAGE) {
+      return
+    }
+
+    try {
+      // Decrypt the message content (context handles this)
+      const decrypted = event.content  // Assume pre-decrypted by context
+
+      // Store the message
+      await this.messageManager.storeIncoming(
+        applicationId,
+        event.pubkey,
+        decrypted,
+        event.id,
+        event.created_at
+      )
+
+      // Parse message type
+      const { type, parsed } = parseMessageType(decrypted)
+
+      // Handle order requests
+      if (type === 'order_request') {
+        const orderReq = parseOrderRequest(decrypted)
+        if (orderReq) {
+          const order = await this.orderManager.createFromNostr(
+            applicationId,
+            event.pubkey,
+            orderReq,
+            event.id
+          )
+
+          // Create invoice and send payment request
+          const withInvoice = await this.orderManager.createInvoice(order.id, applicationId)
+          await this.orderManager.sendPaymentRequestDM(withInvoice)
+
+          console.log(`[Marketplace] Created order ${order.id} from Nostr DM`)
+        }
+      }
+    } catch (e) {
+      console.error('[Marketplace] Error handling Nostr event:', e)
+    }
+  }
+}
+
+// Export types for external use
+export * from './types.js'
+export { EVENT_KINDS, MESSAGE_TYPES } from './nostr/kinds.js'
--- a/src/extensions/marketplace/managers/messageManager.ts
+++ b/src/extensions/marketplace/managers/messageManager.ts
@ -0,0 +1,497 @@
+import {
+  ExtensionContext, ExtensionDatabase,
+  DirectMessage, Customer, MessageType
+} from '../types.js'
+import { generateId } from '../utils/validation.js'
+import { parseMessageType } from '../nostr/parser.js'
+
+/**
+ * Database row for direct message
+ */
+interface MessageRow {
+  id: string
+  application_id: string
+  order_id: string | null
+  customer_pubkey: string
+  message_type: string
+  content: string
+  incoming: number
+  nostr_event_id: string
+  nostr_event_created_at: number
+  created_at: number
+  read: number
+}
+
+/**
+ * Database row for customer
+ */
+interface CustomerRow {
+  pubkey: string
+  application_id: string
+  name: string | null
+  about: string | null
+  picture: string | null
+  total_orders: number
+  total_spent_sats: number
+  unread_messages: number
+  first_seen_at: number
+  last_seen_at: number
+}
+
+/**
+ * Convert database row to DirectMessage object
+ */
+function rowToMessage(row: MessageRow): DirectMessage {
+  return {
+    id: row.id,
+    application_id: row.application_id,
+    order_id: row.order_id || undefined,
+    customer_pubkey: row.customer_pubkey,
+    message_type: row.message_type as MessageType,
+    content: row.content,
+    incoming: row.incoming === 1,
+    nostr_event_id: row.nostr_event_id,
+    nostr_event_created_at: row.nostr_event_created_at,
+    created_at: row.created_at,
+    read: row.read === 1
+  }
+}
+
+/**
+ * Convert database row to Customer object
+ */
+function rowToCustomer(row: CustomerRow): Customer {
+  return {
+    pubkey: row.pubkey,
+    application_id: row.application_id,
+    name: row.name || undefined,
+    about: row.about || undefined,
+    picture: row.picture || undefined,
+    total_orders: row.total_orders,
+    total_spent_sats: row.total_spent_sats,
+    unread_messages: row.unread_messages,
+    first_seen_at: row.first_seen_at,
+    last_seen_at: row.last_seen_at
+  }
+}
+
+/**
+ * Query options for listing messages
+ */
+interface ListMessagesOptions {
+  customer_pubkey?: string
+  order_id?: string
+  incoming_only?: boolean
+  unread_only?: boolean
+  limit?: number
+  offset?: number
+}
+
+/**
+ * Query options for listing customers
+ */
+interface ListCustomersOptions {
+  has_orders?: boolean
+  has_unread?: boolean
+  limit?: number
+  offset?: number
+}
+
+/**
+ * MessageManager - Handles customer DMs and customer management
+ */
+export class MessageManager {
+  constructor(
+    private db: ExtensionDatabase,
+    private ctx: ExtensionContext
+  ) {}
+
+  // ===== Message Methods =====
+
+  /**
+   * Store incoming message from Nostr
+   */
+  async storeIncoming(
+    applicationId: string,
+    customerPubkey: string,
+    decryptedContent: string,
+    nostrEventId: string,
+    nostrEventCreatedAt: number,
+    orderId?: string
+  ): Promise<DirectMessage> {
+    // Parse message type
+    const { type } = parseMessageType(decryptedContent)
+
+    const now = Math.floor(Date.now() / 1000)
+    const id = generateId()
+
+    const message: DirectMessage = {
+      id,
+      application_id: applicationId,
+      order_id: orderId,
+      customer_pubkey: customerPubkey,
+      message_type: type,
+      content: decryptedContent,
+      incoming: true,
+      nostr_event_id: nostrEventId,
+      nostr_event_created_at: nostrEventCreatedAt,
+      created_at: now,
+      read: false
+    }
+
+    // Check for duplicate event
+    const existing = await this.db.query(
+      'SELECT id FROM direct_messages WHERE nostr_event_id = ?',
+      [nostrEventId]
+    )
+    if (existing.length > 0) {
+      return message  // Already stored, return without error
+    }
+
+    // Insert message
+    await this.db.execute(
+      `INSERT INTO direct_messages (
+        id, application_id, order_id, customer_pubkey, message_type,
+        content, incoming, nostr_event_id, nostr_event_created_at,
+        created_at, read
+      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+      [
+        message.id,
+        message.application_id,
+        message.order_id || null,
+        message.customer_pubkey,
+        message.message_type,
+        message.content,
+        1,  // incoming = true
+        message.nostr_event_id,
+        message.nostr_event_created_at,
+        message.created_at,
+        0   // read = false
+      ]
+    )
+
+    // Update customer unread count
+    await this.incrementUnread(applicationId, customerPubkey)
+
+    // Ensure customer exists
+    await this.ensureCustomer(applicationId, customerPubkey)
+
+    return message
+  }
+
+  /**
+   * Store outgoing message (sent by merchant)
+   */
+  async storeOutgoing(
+    applicationId: string,
+    customerPubkey: string,
+    content: string,
+    nostrEventId: string,
+    orderId?: string
+  ): Promise<DirectMessage> {
+    const { type } = parseMessageType(content)
+    const now = Math.floor(Date.now() / 1000)
+    const id = generateId()
+
+    const message: DirectMessage = {
+      id,
+      application_id: applicationId,
+      order_id: orderId,
+      customer_pubkey: customerPubkey,
+      message_type: type,
+      content,
+      incoming: false,
+      nostr_event_id: nostrEventId,
+      nostr_event_created_at: now,
+      created_at: now,
+      read: true  // Outgoing messages are always "read"
+    }
+
+    await this.db.execute(
+      `INSERT INTO direct_messages (
+        id, application_id, order_id, customer_pubkey, message_type,
+        content, incoming, nostr_event_id, nostr_event_created_at,
+        created_at, read
+      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+      [
+        message.id,
+        message.application_id,
+        message.order_id || null,
+        message.customer_pubkey,
+        message.message_type,
+        message.content,
+        0,  // incoming = false
+        message.nostr_event_id,
+        message.nostr_event_created_at,
+        message.created_at,
+        1   // read = true
+      ]
+    )
+
+    return message
+  }
+
+  /**
+   * Get message by ID
+   */
+  async getMessage(id: string, applicationId: string): Promise<DirectMessage | null> {
+    const rows = await this.db.query<MessageRow>(
+      'SELECT * FROM direct_messages WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+
+    if (rows.length === 0) return null
+    return rowToMessage(rows[0])
+  }
+
+  /**
+   * List messages with filters
+   */
+  async listMessages(
+    applicationId: string,
+    options: ListMessagesOptions = {}
+  ): Promise<DirectMessage[]> {
+    let sql = 'SELECT * FROM direct_messages WHERE application_id = ?'
+    const params: any[] = [applicationId]
+
+    if (options.customer_pubkey) {
+      sql += ' AND customer_pubkey = ?'
+      params.push(options.customer_pubkey)
+    }
+
+    if (options.order_id) {
+      sql += ' AND order_id = ?'
+      params.push(options.order_id)
+    }
+
+    if (options.incoming_only) {
+      sql += ' AND incoming = 1'
+    }
+
+    if (options.unread_only) {
+      sql += ' AND read = 0'
+    }
+
+    sql += ' ORDER BY nostr_event_created_at DESC'
+
+    if (options.limit) {
+      sql += ' LIMIT ?'
+      params.push(options.limit)
+      if (options.offset) {
+        sql += ' OFFSET ?'
+        params.push(options.offset)
+      }
+    }
+
+    const rows = await this.db.query<MessageRow>(sql, params)
+    return rows.map(rowToMessage)
+  }
+
+  /**
+   * Get conversation thread with a customer
+   */
+  async getConversation(
+    applicationId: string,
+    customerPubkey: string,
+    limit: number = 50
+  ): Promise<DirectMessage[]> {
+    const rows = await this.db.query<MessageRow>(
+      `SELECT * FROM direct_messages
+       WHERE application_id = ? AND customer_pubkey = ?
+       ORDER BY nostr_event_created_at DESC
+       LIMIT ?`,
+      [applicationId, customerPubkey, limit]
+    )
+
+    // Return in chronological order
+    return rows.map(rowToMessage).reverse()
+  }
+
+  /**
+   * Mark messages as read
+   */
+  async markAsRead(applicationId: string, customerPubkey: string): Promise<number> {
+    const result = await this.db.execute(
+      `UPDATE direct_messages SET read = 1
+       WHERE application_id = ? AND customer_pubkey = ? AND read = 0`,
+      [applicationId, customerPubkey]
+    )
+
+    // Reset customer unread count
+    await this.db.execute(
+      `UPDATE customers SET unread_messages = 0
+       WHERE application_id = ? AND pubkey = ?`,
+      [applicationId, customerPubkey]
+    )
+
+    return result.changes || 0
+  }
+
+  /**
+   * Get unread message count
+   */
+  async getUnreadCount(applicationId: string): Promise<number> {
+    const result = await this.db.query<{ count: number }>(
+      `SELECT COUNT(*) as count FROM direct_messages
+       WHERE application_id = ? AND incoming = 1 AND read = 0`,
+      [applicationId]
+    )
+    return result[0]?.count || 0
+  }
+
+  /**
+   * Send a plain text message to customer
+   */
+  async sendMessage(
+    applicationId: string,
+    customerPubkey: string,
+    message: string,
+    orderId?: string
+  ): Promise<DirectMessage> {
+    // Send via Nostr
+    const eventId = await this.ctx.sendEncryptedDM(
+      applicationId,
+      customerPubkey,
+      message
+    )
+
+    // Store outgoing message
+    return this.storeOutgoing(
+      applicationId,
+      customerPubkey,
+      message,
+      eventId,
+      orderId
+    )
+  }
+
+  // ===== Customer Methods =====
+
+  /**
+   * Get customer by pubkey
+   */
+  async getCustomer(pubkey: string, applicationId: string): Promise<Customer | null> {
+    const rows = await this.db.query<CustomerRow>(
+      'SELECT * FROM customers WHERE pubkey = ? AND application_id = ?',
+      [pubkey, applicationId]
+    )
+
+    if (rows.length === 0) return null
+    return rowToCustomer(rows[0])
+  }
+
+  /**
+   * List customers with filters
+   */
+  async listCustomers(
+    applicationId: string,
+    options: ListCustomersOptions = {}
+  ): Promise<Customer[]> {
+    let sql = 'SELECT * FROM customers WHERE application_id = ?'
+    const params: any[] = [applicationId]
+
+    if (options.has_orders) {
+      sql += ' AND total_orders > 0'
+    }
+
+    if (options.has_unread) {
+      sql += ' AND unread_messages > 0'
+    }
+
+    sql += ' ORDER BY last_seen_at DESC'
+
+    if (options.limit) {
+      sql += ' LIMIT ?'
+      params.push(options.limit)
+      if (options.offset) {
+        sql += ' OFFSET ?'
+        params.push(options.offset)
+      }
+    }
+
+    const rows = await this.db.query<CustomerRow>(sql, params)
+    return rows.map(rowToCustomer)
+  }
+
+  /**
+   * Update customer profile from Nostr metadata
+   */
+  async updateCustomerProfile(
+    pubkey: string,
+    applicationId: string,
+    profile: { name?: string; about?: string; picture?: string }
+  ): Promise<Customer | null> {
+    await this.ensureCustomer(applicationId, pubkey)
+
+    await this.db.execute(
+      `UPDATE customers SET
+        name = COALESCE(?, name),
+        about = COALESCE(?, about),
+        picture = COALESCE(?, picture),
+        last_seen_at = ?
+      WHERE pubkey = ? AND application_id = ?`,
+      [
+        profile.name || null,
+        profile.about || null,
+        profile.picture || null,
+        Math.floor(Date.now() / 1000),
+        pubkey,
+        applicationId
+      ]
+    )
+
+    return this.getCustomer(pubkey, applicationId)
+  }
+
+  /**
+   * Get customer statistics summary
+   */
+  async getCustomerStats(applicationId: string): Promise<{
+    total_customers: number
+    customers_with_orders: number
+    total_unread: number
+  }> {
+    const total = await this.db.query<{ count: number }>(
+      'SELECT COUNT(*) as count FROM customers WHERE application_id = ?',
+      [applicationId]
+    )
+
+    const withOrders = await this.db.query<{ count: number }>(
+      'SELECT COUNT(*) as count FROM customers WHERE application_id = ? AND total_orders > 0',
+      [applicationId]
+    )
+
+    const unread = await this.db.query<{ sum: number }>(
+      'SELECT SUM(unread_messages) as sum FROM customers WHERE application_id = ?',
+      [applicationId]
+    )
+
+    return {
+      total_customers: total[0]?.count || 0,
+      customers_with_orders: withOrders[0]?.count || 0,
+      total_unread: unread[0]?.sum || 0
+    }
+  }
+
+  // ===== Private Helpers =====
+
+  private async ensureCustomer(applicationId: string, pubkey: string): Promise<void> {
+    const now = Math.floor(Date.now() / 1000)
+
+    await this.db.execute(
+      `INSERT INTO customers (pubkey, application_id, first_seen_at, last_seen_at)
+       VALUES (?, ?, ?, ?)
+       ON CONFLICT(pubkey, application_id) DO UPDATE SET
+         last_seen_at = ?`,
+      [pubkey, applicationId, now, now, now]
+    )
+  }
+
+  private async incrementUnread(applicationId: string, pubkey: string): Promise<void> {
+    await this.db.execute(
+      `UPDATE customers SET unread_messages = unread_messages + 1
+       WHERE pubkey = ? AND application_id = ?`,
+      [pubkey, applicationId]
+    )
+  }
+}
--- a/src/extensions/marketplace/managers/orderManager.ts
+++ b/src/extensions/marketplace/managers/orderManager.ts
@ -0,0 +1,607 @@
+import {
+  ExtensionContext, ExtensionDatabase,
+  Order, Stall, Product, NIP15OrderRequest,
+  CreateOrderRequest, OrderItem, OrderStatus
+} from '../types.js'
+import { generateId, validateOrderItems } from '../utils/validation.js'
+import { convertToSats, SupportedCurrency } from '../utils/currency.js'
+import { buildPaymentRequestContent, buildOrderStatusContent } from '../nostr/events.js'
+
+/**
+ * Database row for order
+ */
+interface OrderRow {
+  id: string
+  application_id: string
+  stall_id: string
+  customer_pubkey: string
+  customer_app_user_id: string | null
+  items: string  // JSON
+  shipping_zone_id: string
+  shipping_address: string
+  contact: string  // JSON
+  subtotal_sats: number
+  shipping_sats: number
+  total_sats: number
+  original_currency: string
+  exchange_rate: number | null
+  invoice: string | null
+  invoice_id: string | null
+  status: string
+  nostr_event_id: string | null
+  created_at: number
+  paid_at: number | null
+  shipped_at: number | null
+  completed_at: number | null
+}
+
+/**
+ * Convert database row to Order object
+ */
+function rowToOrder(row: OrderRow): Order {
+  return {
+    id: row.id,
+    application_id: row.application_id,
+    stall_id: row.stall_id,
+    customer_pubkey: row.customer_pubkey,
+    customer_app_user_id: row.customer_app_user_id || undefined,
+    items: JSON.parse(row.items),
+    shipping_zone_id: row.shipping_zone_id,
+    shipping_address: row.shipping_address,
+    contact: JSON.parse(row.contact),
+    subtotal_sats: row.subtotal_sats,
+    shipping_sats: row.shipping_sats,
+    total_sats: row.total_sats,
+    original_currency: row.original_currency as SupportedCurrency,
+    exchange_rate: row.exchange_rate || undefined,
+    invoice: row.invoice || undefined,
+    invoice_id: row.invoice_id || undefined,
+    status: row.status as OrderStatus,
+    nostr_event_id: row.nostr_event_id || undefined,
+    created_at: row.created_at,
+    paid_at: row.paid_at || undefined,
+    shipped_at: row.shipped_at || undefined,
+    completed_at: row.completed_at || undefined
+  }
+}
+
+/**
+ * Query options for listing orders
+ */
+interface ListOrdersOptions {
+  stall_id?: string
+  customer_pubkey?: string
+  status?: OrderStatus
+  limit?: number
+  offset?: number
+}
+
+/**
+ * OrderManager - Handles order lifecycle and payment integration
+ */
+export class OrderManager {
+  constructor(
+    private db: ExtensionDatabase,
+    private ctx: ExtensionContext
+  ) {}
+
+  /**
+   * Create order from NIP-15 order request (via Nostr DM)
+   */
+  async createFromNostr(
+    applicationId: string,
+    customerPubkey: string,
+    orderReq: NIP15OrderRequest,
+    nostrEventId?: string
+  ): Promise<Order> {
+    // Validate items
+    validateOrderItems(orderReq.items)
+
+    // Find stall from first product
+    const firstProduct = await this.getProduct(orderReq.items[0].product_id, applicationId)
+    if (!firstProduct) {
+      throw new Error('Product not found')
+    }
+
+    const stall = await this.getStall(firstProduct.stall_id, applicationId)
+    if (!stall) {
+      throw new Error('Stall not found')
+    }
+
+    // Calculate totals
+    const itemsWithDetails = await this.enrichOrderItems(orderReq.items, applicationId)
+    const { subtotal, shippingCost, total, exchangeRate } = await this.calculateTotals(
+      itemsWithDetails,
+      stall,
+      orderReq.shipping_id
+    )
+
+    const now = Math.floor(Date.now() / 1000)
+    const id = orderReq.id || generateId()
+
+    const order: Order = {
+      id,
+      application_id: applicationId,
+      stall_id: stall.id,
+      customer_pubkey: customerPubkey,
+      items: itemsWithDetails,
+      shipping_zone_id: orderReq.shipping_id,
+      shipping_address: orderReq.address || '',
+      contact: orderReq.contact || {},
+      subtotal_sats: subtotal,
+      shipping_sats: shippingCost,
+      total_sats: total,
+      original_currency: stall.currency,
+      exchange_rate: exchangeRate,
+      status: 'pending',
+      nostr_event_id: nostrEventId,
+      created_at: now
+    }
+
+    // Insert into database
+    await this.insertOrder(order)
+
+    // Reserve inventory
+    await this.reserveInventory(order)
+
+    // Update customer stats
+    await this.updateCustomerStats(applicationId, customerPubkey)
+
+    return order
+  }
+
+  /**
+   * Create order from RPC request (native client)
+   */
+  async createFromRpc(
+    applicationId: string,
+    customerPubkey: string,
+    req: CreateOrderRequest,
+    appUserId?: string
+  ): Promise<Order> {
+    // Validate items
+    validateOrderItems(req.items)
+
+    // Find stall
+    const stall = await this.getStall(req.stall_id, applicationId)
+    if (!stall) {
+      throw new Error('Stall not found')
+    }
+
+    // Calculate totals
+    const itemsWithDetails = await this.enrichOrderItems(req.items, applicationId)
+    const { subtotal, shippingCost, total, exchangeRate } = await this.calculateTotals(
+      itemsWithDetails,
+      stall,
+      req.shipping_zone_id
+    )
+
+    const now = Math.floor(Date.now() / 1000)
+    const id = generateId()
+
+    const order: Order = {
+      id,
+      application_id: applicationId,
+      stall_id: stall.id,
+      customer_pubkey: customerPubkey,
+      customer_app_user_id: appUserId,
+      items: itemsWithDetails,
+      shipping_zone_id: req.shipping_zone_id,
+      shipping_address: req.shipping_address || '',
+      contact: req.contact || {},
+      subtotal_sats: subtotal,
+      shipping_sats: shippingCost,
+      total_sats: total,
+      original_currency: stall.currency,
+      exchange_rate: exchangeRate,
+      status: 'pending',
+      created_at: now
+    }
+
+    // Insert into database
+    await this.insertOrder(order)
+
+    // Reserve inventory
+    await this.reserveInventory(order)
+
+    // Update customer stats
+    await this.updateCustomerStats(applicationId, customerPubkey)
+
+    return order
+  }
+
+  /**
+   * Get order by ID
+   */
+  async get(id: string, applicationId: string): Promise<Order | null> {
+    const rows = await this.db.query<OrderRow>(
+      'SELECT * FROM orders WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+
+    if (rows.length === 0) return null
+    return rowToOrder(rows[0])
+  }
+
+  /**
+   * List orders with filters
+   */
+  async list(applicationId: string, options: ListOrdersOptions = {}): Promise<Order[]> {
+    let sql = 'SELECT * FROM orders WHERE application_id = ?'
+    const params: any[] = [applicationId]
+
+    if (options.stall_id) {
+      sql += ' AND stall_id = ?'
+      params.push(options.stall_id)
+    }
+
+    if (options.customer_pubkey) {
+      sql += ' AND customer_pubkey = ?'
+      params.push(options.customer_pubkey)
+    }
+
+    if (options.status) {
+      sql += ' AND status = ?'
+      params.push(options.status)
+    }
+
+    sql += ' ORDER BY created_at DESC'
+
+    if (options.limit) {
+      sql += ' LIMIT ?'
+      params.push(options.limit)
+      if (options.offset) {
+        sql += ' OFFSET ?'
+        params.push(options.offset)
+      }
+    }
+
+    const rows = await this.db.query<OrderRow>(sql, params)
+    return rows.map(rowToOrder)
+  }
+
+  /**
+   * Create invoice for an order
+   */
+  async createInvoice(id: string, applicationId: string): Promise<Order> {
+    const order = await this.get(id, applicationId)
+    if (!order) {
+      throw new Error('Order not found')
+    }
+
+    if (order.status !== 'pending') {
+      throw new Error(`Order already ${order.status}`)
+    }
+
+    // Create invoice via Lightning.Pub
+    const invoice = await this.ctx.createInvoice(order.total_sats, {
+      memo: `Order ${order.id}`,
+      expiry: 3600,  // 1 hour
+      metadata: {
+        extension: 'marketplace',
+        order_id: order.id
+      }
+    })
+
+    // Update order with invoice
+    await this.db.execute(
+      `UPDATE orders SET invoice = ?, invoice_id = ? WHERE id = ?`,
+      [invoice.paymentRequest, invoice.id, order.id]
+    )
+
+    order.invoice = invoice.paymentRequest
+    order.invoice_id = invoice.id
+
+    return order
+  }
+
+  /**
+   * Handle invoice payment callback
+   */
+  async handlePayment(invoiceId: string): Promise<Order | null> {
+    // Find order by invoice ID
+    const rows = await this.db.query<OrderRow>(
+      'SELECT * FROM orders WHERE invoice_id = ? AND status = ?',
+      [invoiceId, 'pending']
+    )
+
+    if (rows.length === 0) return null
+
+    const order = rowToOrder(rows[0])
+    const now = Math.floor(Date.now() / 1000)
+
+    // Update order status
+    await this.db.execute(
+      `UPDATE orders SET status = ?, paid_at = ? WHERE id = ?`,
+      ['paid', now, order.id]
+    )
+
+    order.status = 'paid'
+    order.paid_at = now
+
+    // Update customer stats
+    await this.updateCustomerSpent(order.application_id, order.customer_pubkey, order.total_sats)
+
+    // Send payment confirmation DM
+    await this.sendOrderStatusDM(order, 'Payment received! Your order is being processed.')
+
+    return order
+  }
+
+  /**
+   * Update order status
+   */
+  async updateStatus(
+    id: string,
+    applicationId: string,
+    status: OrderStatus,
+    message?: string
+  ): Promise<Order | null> {
+    const order = await this.get(id, applicationId)
+    if (!order) return null
+
+    const now = Math.floor(Date.now() / 1000)
+    const updates: string[] = ['status = ?']
+    const params: any[] = [status]
+
+    // Set timestamp based on status
+    if (status === 'paid' && !order.paid_at) {
+      updates.push('paid_at = ?')
+      params.push(now)
+    } else if (status === 'shipped' && !order.shipped_at) {
+      updates.push('shipped_at = ?')
+      params.push(now)
+    } else if (status === 'completed' && !order.completed_at) {
+      updates.push('completed_at = ?')
+      params.push(now)
+    }
+
+    params.push(id, applicationId)
+
+    await this.db.execute(
+      `UPDATE orders SET ${updates.join(', ')} WHERE id = ? AND application_id = ?`,
+      params
+    )
+
+    const updated = await this.get(id, applicationId)
+
+    // Send status update DM
+    if (updated && message) {
+      await this.sendOrderStatusDM(updated, message)
+    }
+
+    // Handle cancellation - restore inventory
+    if (status === 'cancelled' && order.status === 'pending') {
+      await this.restoreInventory(order)
+    }
+
+    return updated
+  }
+
+  /**
+   * Send payment request DM to customer
+   */
+  async sendPaymentRequestDM(order: Order): Promise<void> {
+    if (!order.invoice) {
+      throw new Error('Order has no invoice')
+    }
+
+    const content = buildPaymentRequestContent(order, order.invoice)
+
+    await this.ctx.sendEncryptedDM(
+      order.application_id,
+      order.customer_pubkey,
+      JSON.stringify(content)
+    )
+  }
+
+  /**
+   * Send order status update DM to customer
+   */
+  async sendOrderStatusDM(order: Order, message: string): Promise<void> {
+    const content = buildOrderStatusContent(order, message)
+
+    await this.ctx.sendEncryptedDM(
+      order.application_id,
+      order.customer_pubkey,
+      JSON.stringify(content)
+    )
+  }
+
+  // ===== Private Helpers =====
+
+  private async insertOrder(order: Order): Promise<void> {
+    await this.db.execute(
+      `INSERT INTO orders (
+        id, application_id, stall_id, customer_pubkey, customer_app_user_id,
+        items, shipping_zone_id, shipping_address, contact,
+        subtotal_sats, shipping_sats, total_sats, original_currency, exchange_rate,
+        invoice, invoice_id, status, nostr_event_id, created_at
+      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+      [
+        order.id,
+        order.application_id,
+        order.stall_id,
+        order.customer_pubkey,
+        order.customer_app_user_id || null,
+        JSON.stringify(order.items),
+        order.shipping_zone_id,
+        order.shipping_address,
+        JSON.stringify(order.contact),
+        order.subtotal_sats,
+        order.shipping_sats,
+        order.total_sats,
+        order.original_currency,
+        order.exchange_rate || null,
+        order.invoice || null,
+        order.invoice_id || null,
+        order.status,
+        order.nostr_event_id || null,
+        order.created_at
+      ]
+    )
+  }
+
+  private async getStall(id: string, applicationId: string): Promise<Stall | null> {
+    const rows = await this.db.query(
+      'SELECT * FROM stalls WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+    if (rows.length === 0) return null
+
+    const row = rows[0] as any
+    return {
+      ...row,
+      shipping_zones: JSON.parse(row.shipping_zones)
+    }
+  }
+
+  private async getProduct(id: string, applicationId: string): Promise<Product | null> {
+    const rows = await this.db.query(
+      'SELECT * FROM products WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+    if (rows.length === 0) return null
+
+    const row = rows[0] as any
+    return {
+      ...row,
+      images: JSON.parse(row.images),
+      categories: JSON.parse(row.categories),
+      specs: row.specs ? JSON.parse(row.specs) : undefined,
+      active: row.active === 1
+    }
+  }
+
+  private async enrichOrderItems(
+    items: Array<{ product_id: string; quantity: number }>,
+    applicationId: string
+  ): Promise<OrderItem[]> {
+    const enriched: OrderItem[] = []
+
+    for (const item of items) {
+      const product = await this.getProduct(item.product_id, applicationId)
+      if (!product) {
+        throw new Error(`Product ${item.product_id} not found`)
+      }
+
+      if (!product.active) {
+        throw new Error(`Product ${product.name} is not available`)
+      }
+
+      // Check stock
+      if (product.quantity !== -1 && product.quantity < item.quantity) {
+        throw new Error(`Insufficient stock for ${product.name}`)
+      }
+
+      enriched.push({
+        product_id: product.id,
+        product_name: product.name,
+        quantity: item.quantity,
+        unit_price: product.price
+      })
+    }
+
+    return enriched
+  }
+
+  private async calculateTotals(
+    items: OrderItem[],
+    stall: Stall,
+    shippingZoneId: string
+  ): Promise<{
+    subtotal: number
+    shippingCost: number
+    total: number
+    exchangeRate?: number
+  }> {
+    // Calculate subtotal in original currency
+    const subtotalOriginal = items.reduce(
+      (sum, item) => sum + item.unit_price * item.quantity,
+      0
+    )
+
+    // Find shipping zone
+    const shippingZone = stall.shipping_zones.find(z => z.id === shippingZoneId)
+    if (!shippingZone) {
+      throw new Error('Invalid shipping zone')
+    }
+
+    const shippingOriginal = shippingZone.cost
+
+    // Convert to sats if needed
+    let subtotal: number
+    let shippingCost: number
+    let exchangeRate: number | undefined
+
+    if (stall.currency === 'sat') {
+      subtotal = subtotalOriginal
+      shippingCost = shippingOriginal
+    } else {
+      subtotal = await convertToSats(this.db, subtotalOriginal, stall.currency)
+      shippingCost = await convertToSats(this.db, shippingOriginal, stall.currency)
+      exchangeRate = subtotal / subtotalOriginal
+    }
+
+    return {
+      subtotal,
+      shippingCost,
+      total: subtotal + shippingCost,
+      exchangeRate
+    }
+  }
+
+  private async reserveInventory(order: Order): Promise<void> {
+    for (const item of order.items) {
+      await this.db.execute(
+        `UPDATE products SET
+          quantity = CASE
+            WHEN quantity = -1 THEN -1
+            ELSE quantity - ?
+          END
+        WHERE id = ? AND quantity != -1`,
+        [item.quantity, item.product_id]
+      )
+    }
+  }
+
+  private async restoreInventory(order: Order): Promise<void> {
+    for (const item of order.items) {
+      await this.db.execute(
+        `UPDATE products SET
+          quantity = CASE
+            WHEN quantity = -1 THEN -1
+            ELSE quantity + ?
+          END
+        WHERE id = ? AND quantity != -1`,
+        [item.quantity, item.product_id]
+      )
+    }
+  }
+
+  private async updateCustomerStats(applicationId: string, pubkey: string): Promise<void> {
+    const now = Math.floor(Date.now() / 1000)
+
+    await this.db.execute(
+      `INSERT INTO customers (pubkey, application_id, total_orders, first_seen_at, last_seen_at)
+       VALUES (?, ?, 1, ?, ?)
+       ON CONFLICT(pubkey, application_id) DO UPDATE SET
+         total_orders = total_orders + 1,
+         last_seen_at = ?`,
+      [pubkey, applicationId, now, now, now]
+    )
+  }
+
+  private async updateCustomerSpent(
+    applicationId: string,
+    pubkey: string,
+    amount: number
+  ): Promise<void> {
+    await this.db.execute(
+      `UPDATE customers SET
+        total_spent_sats = total_spent_sats + ?
+      WHERE pubkey = ? AND application_id = ?`,
+      [amount, pubkey, applicationId]
+    )
+  }
+}
--- a/src/extensions/marketplace/managers/productManager.ts
+++ b/src/extensions/marketplace/managers/productManager.ts
@ -0,0 +1,466 @@
+import {
+  ExtensionContext, ExtensionDatabase,
+  Product, Stall, CreateProductRequest, UpdateProductRequest
+} from '../types.js'
+import { generateId, validateProduct } from '../utils/validation.js'
+import { buildProductEvent, buildDeleteEvent } from '../nostr/events.js'
+
+/**
+ * Database row for product
+ */
+interface ProductRow {
+  id: string
+  stall_id: string
+  application_id: string
+  name: string
+  description: string
+  images: string  // JSON array
+  price: number
+  quantity: number
+  categories: string  // JSON array
+  shipping_cost: number | null
+  specs: string | null  // JSON array
+  active: number
+  nostr_event_id: string | null
+  nostr_event_created_at: number | null
+  created_at: number
+  updated_at: number
+}
+
+/**
+ * Convert database row to Product object
+ */
+function rowToProduct(row: ProductRow): Product {
+  return {
+    id: row.id,
+    stall_id: row.stall_id,
+    application_id: row.application_id,
+    name: row.name,
+    description: row.description,
+    images: JSON.parse(row.images),
+    price: row.price,
+    quantity: row.quantity,
+    categories: JSON.parse(row.categories),
+    shipping_cost: row.shipping_cost ?? undefined,
+    specs: row.specs ? JSON.parse(row.specs) : undefined,
+    active: row.active === 1,
+    nostr_event_id: row.nostr_event_id || undefined,
+    nostr_event_created_at: row.nostr_event_created_at || undefined,
+    created_at: row.created_at,
+    updated_at: row.updated_at
+  }
+}
+
+/**
+ * Query options for listing products
+ */
+interface ListProductsOptions {
+  stall_id?: string
+  category?: string
+  active_only?: boolean
+  limit?: number
+  offset?: number
+}
+
+/**
+ * ProductManager - Handles product CRUD, inventory, and Nostr publishing
+ */
+export class ProductManager {
+  constructor(
+    private db: ExtensionDatabase,
+    private ctx: ExtensionContext
+  ) {}
+
+  /**
+   * Create a new product
+   */
+  async create(
+    applicationId: string,
+    stallId: string,
+    req: CreateProductRequest
+  ): Promise<Product> {
+    // Validate request
+    validateProduct(req)
+
+    // Verify stall exists and belongs to application
+    const stallRows = await this.db.query(
+      'SELECT * FROM stalls WHERE id = ? AND application_id = ?',
+      [stallId, applicationId]
+    )
+    if (stallRows.length === 0) {
+      throw new Error('Stall not found')
+    }
+
+    const now = Math.floor(Date.now() / 1000)
+    const id = generateId()
+
+    const product: Product = {
+      id,
+      stall_id: stallId,
+      application_id: applicationId,
+      name: req.name.trim(),
+      description: req.description?.trim() || '',
+      images: req.images || [],
+      price: req.price,
+      quantity: req.quantity ?? -1,  // -1 = unlimited
+      categories: req.categories || [],
+      shipping_cost: req.shipping_cost,
+      specs: req.specs,
+      active: true,
+      created_at: now,
+      updated_at: now
+    }
+
+    // Insert into database
+    await this.db.execute(
+      `INSERT INTO products (
+        id, stall_id, application_id, name, description, images,
+        price, quantity, categories, shipping_cost, specs, active,
+        created_at, updated_at
+      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+      [
+        product.id,
+        product.stall_id,
+        product.application_id,
+        product.name,
+        product.description,
+        JSON.stringify(product.images),
+        product.price,
+        product.quantity,
+        JSON.stringify(product.categories),
+        product.shipping_cost ?? null,
+        product.specs ? JSON.stringify(product.specs) : null,
+        product.active ? 1 : 0,
+        product.created_at,
+        product.updated_at
+      ]
+    )
+
+    // Publish to Nostr if auto-publish enabled
+    if (req.publish_to_nostr !== false) {
+      await this.publishToNostr(product)
+    }
+
+    return product
+  }
+
+  /**
+   * Get product by ID
+   */
+  async get(id: string, applicationId: string): Promise<Product | null> {
+    const rows = await this.db.query<ProductRow>(
+      'SELECT * FROM products WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+
+    if (rows.length === 0) return null
+    return rowToProduct(rows[0])
+  }
+
+  /**
+   * List products with optional filters
+   */
+  async list(applicationId: string, options: ListProductsOptions = {}): Promise<Product[]> {
+    let sql = 'SELECT * FROM products WHERE application_id = ?'
+    const params: any[] = [applicationId]
+
+    if (options.stall_id) {
+      sql += ' AND stall_id = ?'
+      params.push(options.stall_id)
+    }
+
+    if (options.active_only !== false) {
+      sql += ' AND active = 1'
+    }
+
+    if (options.category) {
+      // Search in JSON array
+      sql += ' AND categories LIKE ?'
+      params.push(`%"${options.category}"%`)
+    }
+
+    sql += ' ORDER BY created_at DESC'
+
+    if (options.limit) {
+      sql += ' LIMIT ?'
+      params.push(options.limit)
+      if (options.offset) {
+        sql += ' OFFSET ?'
+        params.push(options.offset)
+      }
+    }
+
+    const rows = await this.db.query<ProductRow>(sql, params)
+    return rows.map(rowToProduct)
+  }
+
+  /**
+   * Update a product
+   */
+  async update(
+    id: string,
+    applicationId: string,
+    req: UpdateProductRequest
+  ): Promise<Product | null> {
+    const existing = await this.get(id, applicationId)
+    if (!existing) return null
+
+    // Build updated product
+    const updated: Product = {
+      ...existing,
+      name: req.name?.trim() ?? existing.name,
+      description: req.description?.trim() ?? existing.description,
+      images: req.images ?? existing.images,
+      price: req.price ?? existing.price,
+      quantity: req.quantity ?? existing.quantity,
+      categories: req.categories ?? existing.categories,
+      shipping_cost: req.shipping_cost ?? existing.shipping_cost,
+      specs: req.specs ?? existing.specs,
+      active: req.active ?? existing.active,
+      updated_at: Math.floor(Date.now() / 1000)
+    }
+
+    // Validate merged product
+    validateProduct({
+      name: updated.name,
+      price: updated.price,
+      quantity: updated.quantity,
+      images: updated.images,
+      categories: updated.categories
+    })
+
+    // Update database
+    await this.db.execute(
+      `UPDATE products SET
+        name = ?, description = ?, images = ?, price = ?,
+        quantity = ?, categories = ?, shipping_cost = ?,
+        specs = ?, active = ?, updated_at = ?
+      WHERE id = ? AND application_id = ?`,
+      [
+        updated.name,
+        updated.description,
+        JSON.stringify(updated.images),
+        updated.price,
+        updated.quantity,
+        JSON.stringify(updated.categories),
+        updated.shipping_cost ?? null,
+        updated.specs ? JSON.stringify(updated.specs) : null,
+        updated.active ? 1 : 0,
+        updated.updated_at,
+        id,
+        applicationId
+      ]
+    )
+
+    // Republish to Nostr
+    if (req.publish_to_nostr !== false && updated.active) {
+      await this.publishToNostr(updated)
+    } else if (!updated.active && existing.nostr_event_id) {
+      // Unpublish if deactivated
+      await this.unpublishFromNostr(updated)
+    }
+
+    return updated
+  }
+
+  /**
+   * Delete a product
+   */
+  async delete(id: string, applicationId: string): Promise<boolean> {
+    const product = await this.get(id, applicationId)
+    if (!product) return false
+
+    // Check for pending orders
+    const orders = await this.db.query(
+      `SELECT COUNT(*) as count FROM orders
+       WHERE items LIKE ? AND status IN ('pending', 'paid')`,
+      [`%"${id}"%`]
+    )
+    if ((orders[0] as any).count > 0) {
+      throw new Error('Cannot delete product with pending orders')
+    }
+
+    // Unpublish from Nostr
+    if (product.nostr_event_id) {
+      await this.unpublishFromNostr(product)
+    }
+
+    // Delete from database
+    await this.db.execute(
+      'DELETE FROM products WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+
+    return true
+  }
+
+  /**
+   * Update product quantity (for inventory management)
+   */
+  async updateQuantity(
+    id: string,
+    applicationId: string,
+    delta: number
+  ): Promise<number> {
+    const product = await this.get(id, applicationId)
+    if (!product) {
+      throw new Error('Product not found')
+    }
+
+    // -1 means unlimited
+    if (product.quantity === -1) {
+      return -1
+    }
+
+    const newQuantity = Math.max(0, product.quantity + delta)
+
+    await this.db.execute(
+      'UPDATE products SET quantity = ?, updated_at = ? WHERE id = ?',
+      [newQuantity, Math.floor(Date.now() / 1000), id]
+    )
+
+    // Republish if quantity changed and product is published
+    if (product.nostr_event_id) {
+      const updated = await this.get(id, applicationId)
+      if (updated) await this.publishToNostr(updated)
+    }
+
+    return newQuantity
+  }
+
+  /**
+   * Check if products are in stock
+   */
+  async checkStock(
+    items: Array<{ product_id: string; quantity: number }>,
+    applicationId: string
+  ): Promise<{ available: boolean; unavailable: string[] }> {
+    const unavailable: string[] = []
+
+    for (const item of items) {
+      const product = await this.get(item.product_id, applicationId)
+
+      if (!product) {
+        unavailable.push(item.product_id)
+        continue
+      }
+
+      if (!product.active) {
+        unavailable.push(item.product_id)
+        continue
+      }
+
+      // -1 means unlimited
+      if (product.quantity !== -1 && product.quantity < item.quantity) {
+        unavailable.push(item.product_id)
+      }
+    }
+
+    return {
+      available: unavailable.length === 0,
+      unavailable
+    }
+  }
+
+  /**
+   * Publish product to Nostr (kind 30018)
+   */
+  async publishToNostr(product: Product): Promise<string | null> {
+    try {
+      // Get stall for currency info
+      const stallRows = await this.db.query(
+        'SELECT * FROM stalls WHERE id = ?',
+        [product.stall_id]
+      )
+      if (stallRows.length === 0) return null
+
+      const stall = stallRows[0] as any
+      const stallObj: Stall = {
+        ...stall,
+        shipping_zones: JSON.parse(stall.shipping_zones)
+      }
+
+      // Get application's Nostr pubkey
+      const app = await this.ctx.getApplication(product.application_id)
+      if (!app || !app.nostr_public) {
+        console.warn(`No Nostr pubkey for application ${product.application_id}`)
+        return null
+      }
+
+      // Build the event
+      const event = buildProductEvent(product, stallObj, app.nostr_public)
+
+      // Sign and publish
+      const eventId = await this.ctx.publishNostrEvent(event)
+
+      // Update database with event info
+      if (eventId) {
+        await this.db.execute(
+          `UPDATE products SET
+            nostr_event_id = ?,
+            nostr_event_created_at = ?
+          WHERE id = ?`,
+          [eventId, event.created_at, product.id]
+        )
+      }
+
+      return eventId
+    } catch (e) {
+      console.error('Failed to publish product to Nostr:', e)
+      return null
+    }
+  }
+
+  /**
+   * Unpublish product from Nostr (kind 5 deletion)
+   */
+  async unpublishFromNostr(product: Product): Promise<boolean> {
+    if (!product.nostr_event_id) return false
+
+    try {
+      const app = await this.ctx.getApplication(product.application_id)
+      if (!app || !app.nostr_public) return false
+
+      const deleteEvent = buildDeleteEvent(
+        product.nostr_event_id,
+        30018,  // PRODUCT kind
+        app.nostr_public,
+        `Product ${product.name} removed`
+      )
+
+      await this.ctx.publishNostrEvent(deleteEvent)
+
+      // Clear event info
+      await this.db.execute(
+        `UPDATE products SET
+          nostr_event_id = NULL,
+          nostr_event_created_at = NULL
+        WHERE id = ?`,
+        [product.id]
+      )
+
+      return true
+    } catch (e) {
+      console.error('Failed to unpublish product from Nostr:', e)
+      return false
+    }
+  }
+
+  /**
+   * Republish all products for a stall
+   */
+  async republishAllForStall(stallId: string, applicationId: string): Promise<number> {
+    const products = await this.list(applicationId, {
+      stall_id: stallId,
+      active_only: true
+    })
+
+    let count = 0
+    for (const product of products) {
+      const eventId = await this.publishToNostr(product)
+      if (eventId) count++
+    }
+
+    return count
+  }
+}
--- a/src/extensions/marketplace/managers/stallManager.ts
+++ b/src/extensions/marketplace/managers/stallManager.ts
@ -0,0 +1,305 @@
+import {
+  ExtensionContext, ExtensionDatabase,
+  Stall, CreateStallRequest, UpdateStallRequest
+} from '../types.js'
+import { generateId, validateStall } from '../utils/validation.js'
+import { buildStallEvent, buildDeleteEvent } from '../nostr/events.js'
+
+/**
+ * Database row for stall
+ */
+interface StallRow {
+  id: string
+  application_id: string
+  name: string
+  description: string
+  currency: string
+  shipping_zones: string  // JSON
+  image_url: string | null
+  nostr_event_id: string | null
+  nostr_event_created_at: number | null
+  created_at: number
+  updated_at: number
+}
+
+/**
+ * Convert database row to Stall object
+ */
+function rowToStall(row: StallRow): Stall {
+  return {
+    id: row.id,
+    application_id: row.application_id,
+    name: row.name,
+    description: row.description,
+    currency: row.currency as Stall['currency'],
+    shipping_zones: JSON.parse(row.shipping_zones),
+    image_url: row.image_url || undefined,
+    nostr_event_id: row.nostr_event_id || undefined,
+    nostr_event_created_at: row.nostr_event_created_at || undefined,
+    created_at: row.created_at,
+    updated_at: row.updated_at
+  }
+}
+
+/**
+ * StallManager - Handles stall CRUD and Nostr publishing
+ */
+export class StallManager {
+  constructor(
+    private db: ExtensionDatabase,
+    private ctx: ExtensionContext
+  ) {}
+
+  /**
+   * Create a new stall
+   */
+  async create(applicationId: string, req: CreateStallRequest): Promise<Stall> {
+    // Validate request
+    validateStall(req)
+
+    const now = Math.floor(Date.now() / 1000)
+    const id = generateId()
+
+    // Assign IDs to shipping zones if not provided
+    const shippingZones = req.shipping_zones.map(zone => ({
+      id: zone.id || generateId(),
+      name: zone.name,
+      cost: zone.cost,
+      regions: zone.regions
+    }))
+
+    const stall: Stall = {
+      id,
+      application_id: applicationId,
+      name: req.name.trim(),
+      description: req.description?.trim() || '',
+      currency: req.currency,
+      shipping_zones: shippingZones,
+      image_url: req.image_url,
+      created_at: now,
+      updated_at: now
+    }
+
+    // Insert into database
+    await this.db.execute(
+      `INSERT INTO stalls (
+        id, application_id, name, description, currency,
+        shipping_zones, image_url, created_at, updated_at
+      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+      [
+        stall.id,
+        stall.application_id,
+        stall.name,
+        stall.description,
+        stall.currency,
+        JSON.stringify(stall.shipping_zones),
+        stall.image_url || null,
+        stall.created_at,
+        stall.updated_at
+      ]
+    )
+
+    // Publish to Nostr if auto-publish enabled
+    if (req.publish_to_nostr !== false) {
+      await this.publishToNostr(stall)
+    }
+
+    return stall
+  }
+
+  /**
+   * Get stall by ID
+   */
+  async get(id: string, applicationId: string): Promise<Stall | null> {
+    const rows = await this.db.query<StallRow>(
+      'SELECT * FROM stalls WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+
+    if (rows.length === 0) return null
+    return rowToStall(rows[0])
+  }
+
+  /**
+   * List all stalls for an application
+   */
+  async list(applicationId: string): Promise<Stall[]> {
+    const rows = await this.db.query<StallRow>(
+      'SELECT * FROM stalls WHERE application_id = ? ORDER BY created_at DESC',
+      [applicationId]
+    )
+
+    return rows.map(rowToStall)
+  }
+
+  /**
+   * Update a stall
+   */
+  async update(
+    id: string,
+    applicationId: string,
+    req: UpdateStallRequest
+  ): Promise<Stall | null> {
+    const existing = await this.get(id, applicationId)
+    if (!existing) return null
+
+    // Build updated stall
+    const updated: Stall = {
+      ...existing,
+      name: req.name?.trim() ?? existing.name,
+      description: req.description?.trim() ?? existing.description,
+      currency: req.currency ?? existing.currency,
+      shipping_zones: req.shipping_zones ?? existing.shipping_zones,
+      image_url: req.image_url ?? existing.image_url,
+      updated_at: Math.floor(Date.now() / 1000)
+    }
+
+    // Validate merged stall
+    validateStall({
+      name: updated.name,
+      currency: updated.currency,
+      shipping_zones: updated.shipping_zones
+    })
+
+    // Update database
+    await this.db.execute(
+      `UPDATE stalls SET
+        name = ?, description = ?, currency = ?,
+        shipping_zones = ?, image_url = ?, updated_at = ?
+      WHERE id = ? AND application_id = ?`,
+      [
+        updated.name,
+        updated.description,
+        updated.currency,
+        JSON.stringify(updated.shipping_zones),
+        updated.image_url || null,
+        updated.updated_at,
+        id,
+        applicationId
+      ]
+    )
+
+    // Republish to Nostr (updates parameterized replaceable event)
+    if (req.publish_to_nostr !== false) {
+      await this.publishToNostr(updated)
+    }
+
+    return updated
+  }
+
+  /**
+   * Delete a stall
+   */
+  async delete(id: string, applicationId: string): Promise<boolean> {
+    const stall = await this.get(id, applicationId)
+    if (!stall) return false
+
+    // Check for products
+    const products = await this.db.query(
+      'SELECT COUNT(*) as count FROM products WHERE stall_id = ?',
+      [id]
+    )
+    if ((products[0] as any).count > 0) {
+      throw new Error('Cannot delete stall with existing products')
+    }
+
+    // Publish deletion event to Nostr if it was published
+    if (stall.nostr_event_id) {
+      await this.unpublishFromNostr(stall)
+    }
+
+    // Delete from database
+    await this.db.execute(
+      'DELETE FROM stalls WHERE id = ? AND application_id = ?',
+      [id, applicationId]
+    )
+
+    return true
+  }
+
+  /**
+   * Publish stall to Nostr (kind 30017)
+   */
+  async publishToNostr(stall: Stall): Promise<string | null> {
+    try {
+      // Get application's Nostr pubkey
+      const app = await this.ctx.getApplication(stall.application_id)
+      if (!app || !app.nostr_public) {
+        console.warn(`No Nostr pubkey for application ${stall.application_id}`)
+        return null
+      }
+
+      // Build the event
+      const event = buildStallEvent(stall, app.nostr_public)
+
+      // Sign and publish via context
+      const eventId = await this.ctx.publishNostrEvent(event)
+
+      // Update database with event info
+      if (eventId) {
+        await this.db.execute(
+          `UPDATE stalls SET
+            nostr_event_id = ?,
+            nostr_event_created_at = ?
+          WHERE id = ?`,
+          [eventId, event.created_at, stall.id]
+        )
+      }
+
+      return eventId
+    } catch (e) {
+      console.error('Failed to publish stall to Nostr:', e)
+      return null
+    }
+  }
+
+  /**
+   * Unpublish stall from Nostr (kind 5 deletion)
+   */
+  async unpublishFromNostr(stall: Stall): Promise<boolean> {
+    if (!stall.nostr_event_id) return false
+
+    try {
+      const app = await this.ctx.getApplication(stall.application_id)
+      if (!app || !app.nostr_public) return false
+
+      const deleteEvent = buildDeleteEvent(
+        stall.nostr_event_id,
+        30017,  // STALL kind
+        app.nostr_public,
+        `Stall ${stall.name} removed`
+      )
+
+      await this.ctx.publishNostrEvent(deleteEvent)
+
+      // Clear event info from database
+      await this.db.execute(
+        `UPDATE stalls SET
+          nostr_event_id = NULL,
+          nostr_event_created_at = NULL
+        WHERE id = ?`,
+        [stall.id]
+      )
+
+      return true
+    } catch (e) {
+      console.error('Failed to unpublish stall from Nostr:', e)
+      return false
+    }
+  }
+
+  /**
+   * Republish all stalls for an application
+   */
+  async republishAll(applicationId: string): Promise<number> {
+    const stalls = await this.list(applicationId)
+    let count = 0
+
+    for (const stall of stalls) {
+      const eventId = await this.publishToNostr(stall)
+      if (eventId) count++
+    }
+
+    return count
+  }
+}
--- a/src/extensions/marketplace/migrations.ts
+++ b/src/extensions/marketplace/migrations.ts
@ -0,0 +1,194 @@
+import { ExtensionDatabase } from './types.js'
+
+export interface ExtensionMigration {
+  version: number
+  description: string
+  up(db: ExtensionDatabase): Promise<void>
+  down?(db: ExtensionDatabase): Promise<void>
+}
+
+export const migrations: ExtensionMigration[] = [
+  {
+    version: 1,
+    description: 'Create core marketplace tables',
+    up: async (db: ExtensionDatabase) => {
+      // Stalls table
+      await db.execute(`
+        CREATE TABLE IF NOT EXISTS stalls (
+          id TEXT PRIMARY KEY,
+          application_id TEXT NOT NULL,
+          name TEXT NOT NULL,
+          description TEXT DEFAULT '',
+          currency TEXT NOT NULL DEFAULT 'sat',
+          shipping_zones TEXT NOT NULL DEFAULT '[]',
+          image_url TEXT,
+          nostr_event_id TEXT,
+          nostr_event_created_at INTEGER,
+          created_at INTEGER NOT NULL,
+          updated_at INTEGER NOT NULL
+        )
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_stalls_app
+        ON stalls(application_id)
+      `)
+
+      // Products table
+      await db.execute(`
+        CREATE TABLE IF NOT EXISTS products (
+          id TEXT PRIMARY KEY,
+          stall_id TEXT NOT NULL,
+          application_id TEXT NOT NULL,
+          name TEXT NOT NULL,
+          description TEXT DEFAULT '',
+          images TEXT NOT NULL DEFAULT '[]',
+          price INTEGER NOT NULL,
+          quantity INTEGER NOT NULL DEFAULT -1,
+          categories TEXT NOT NULL DEFAULT '[]',
+          shipping_cost INTEGER,
+          specs TEXT DEFAULT '[]',
+          active INTEGER NOT NULL DEFAULT 1,
+          nostr_event_id TEXT,
+          nostr_event_created_at INTEGER,
+          created_at INTEGER NOT NULL,
+          updated_at INTEGER NOT NULL,
+          FOREIGN KEY (stall_id) REFERENCES stalls(id)
+        )
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_products_stall
+        ON products(stall_id)
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_products_app
+        ON products(application_id)
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_products_active
+        ON products(active, application_id)
+      `)
+
+      // Orders table
+      await db.execute(`
+        CREATE TABLE IF NOT EXISTS orders (
+          id TEXT PRIMARY KEY,
+          application_id TEXT NOT NULL,
+          stall_id TEXT NOT NULL,
+          customer_pubkey TEXT NOT NULL,
+          customer_app_user_id TEXT,
+          items TEXT NOT NULL,
+          shipping_zone_id TEXT NOT NULL,
+          shipping_address TEXT NOT NULL,
+          contact TEXT NOT NULL,
+          subtotal_sats INTEGER NOT NULL,
+          shipping_sats INTEGER NOT NULL,
+          total_sats INTEGER NOT NULL,
+          original_currency TEXT NOT NULL,
+          exchange_rate REAL,
+          invoice TEXT,
+          invoice_id TEXT,
+          status TEXT NOT NULL DEFAULT 'pending',
+          nostr_event_id TEXT,
+          created_at INTEGER NOT NULL,
+          paid_at INTEGER,
+          shipped_at INTEGER,
+          completed_at INTEGER
+        )
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_orders_app
+        ON orders(application_id)
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_orders_customer
+        ON orders(customer_pubkey, application_id)
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_orders_status
+        ON orders(status, application_id)
+      `)
+
+      // Direct messages table
+      await db.execute(`
+        CREATE TABLE IF NOT EXISTS direct_messages (
+          id TEXT PRIMARY KEY,
+          application_id TEXT NOT NULL,
+          order_id TEXT,
+          customer_pubkey TEXT NOT NULL,
+          message_type TEXT NOT NULL,
+          content TEXT NOT NULL,
+          incoming INTEGER NOT NULL,
+          nostr_event_id TEXT NOT NULL UNIQUE,
+          nostr_event_created_at INTEGER NOT NULL,
+          created_at INTEGER NOT NULL,
+          read INTEGER NOT NULL DEFAULT 0
+        )
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_dm_customer
+        ON direct_messages(customer_pubkey, application_id)
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_dm_order
+        ON direct_messages(order_id)
+      `)
+
+      await db.execute(`
+        CREATE INDEX IF NOT EXISTS idx_dm_unread
+        ON direct_messages(read, application_id)
+      `)
+
+      // Customers table
+      await db.execute(`
+        CREATE TABLE IF NOT EXISTS customers (
+          pubkey TEXT NOT NULL,
+          application_id TEXT NOT NULL,
+          name TEXT,
+          about TEXT,
+          picture TEXT,
+          total_orders INTEGER NOT NULL DEFAULT 0,
+          total_spent_sats INTEGER NOT NULL DEFAULT 0,
+          unread_messages INTEGER NOT NULL DEFAULT 0,
+          first_seen_at INTEGER NOT NULL,
+          last_seen_at INTEGER NOT NULL,
+          PRIMARY KEY (pubkey, application_id)
+        )
+      `)
+    },
+
+    down: async (db: ExtensionDatabase) => {
+      await db.execute('DROP TABLE IF EXISTS customers')
+      await db.execute('DROP TABLE IF EXISTS direct_messages')
+      await db.execute('DROP TABLE IF EXISTS orders')
+      await db.execute('DROP TABLE IF EXISTS products')
+      await db.execute('DROP TABLE IF EXISTS stalls')
+    }
+  },
+
+  {
+    version: 2,
+    description: 'Add exchange rates cache table',
+    up: async (db: ExtensionDatabase) => {
+      await db.execute(`
+        CREATE TABLE IF NOT EXISTS exchange_rates (
+          currency TEXT PRIMARY KEY,
+          rate_sats INTEGER NOT NULL,
+          updated_at INTEGER NOT NULL
+        )
+      `)
+    },
+
+    down: async (db: ExtensionDatabase) => {
+      await db.execute('DROP TABLE IF EXISTS exchange_rates')
+    }
+  }
+]
--- a/src/extensions/marketplace/nostr/events.ts
+++ b/src/extensions/marketplace/nostr/events.ts
@ -0,0 +1,164 @@
+import { EVENT_KINDS } from './kinds.js'
+import {
+  Stall, Product, Order,
+  NIP15Stall, NIP15Product, NIP15PaymentRequest, NIP15OrderStatusUpdate
+} from '../types.js'
+
+/**
+ * Unsigned Nostr event structure
+ */
+export interface UnsignedEvent {
+  kind: number
+  pubkey: string
+  created_at: number
+  tags: string[][]
+  content: string
+  id?: string
+}
+
+/**
+ * Build NIP-15 stall event (kind 30017)
+ */
+export function buildStallEvent(stall: Stall, pubkey: string): UnsignedEvent {
+  const nip15Stall: NIP15Stall = {
+    id: stall.id,
+    name: stall.name,
+    description: stall.description,
+    currency: stall.currency,
+    shipping: stall.shipping_zones.map(zone => ({
+      id: zone.id,
+      name: zone.name,
+      cost: zone.cost,
+      regions: zone.regions
+    }))
+  }
+
+  return {
+    kind: EVENT_KINDS.STALL,
+    pubkey,
+    created_at: Math.floor(Date.now() / 1000),
+    tags: [
+      ['d', stall.id],  // Unique identifier for parameterized replaceable
+    ],
+    content: JSON.stringify(nip15Stall)
+  }
+}
+
+/**
+ * Build NIP-15 product event (kind 30018)
+ */
+export function buildProductEvent(product: Product, stall: Stall, pubkey: string): UnsignedEvent {
+  const nip15Product: NIP15Product = {
+    id: product.id,
+    stall_id: product.stall_id,
+    name: product.name,
+    description: product.description,
+    images: product.images,
+    currency: stall.currency,
+    price: product.price,
+    quantity: product.quantity,
+    specs: product.specs?.map(s => [s.key, s.value] as [string, string])
+  }
+
+  // Add shipping costs if different from stall defaults
+  if (product.shipping_cost !== undefined) {
+    nip15Product.shipping = stall.shipping_zones.map(zone => ({
+      id: zone.id,
+      cost: product.shipping_cost!
+    }))
+  }
+
+  const tags: string[][] = [
+    ['d', product.id],  // Unique identifier
+  ]
+
+  // Add category tags
+  for (const category of product.categories) {
+    tags.push(['t', category])
+  }
+
+  return {
+    kind: EVENT_KINDS.PRODUCT,
+    pubkey,
+    created_at: Math.floor(Date.now() / 1000),
+    tags,
+    content: JSON.stringify(nip15Product)
+  }
+}
+
+/**
+ * Build deletion event (kind 5)
+ */
+export function buildDeleteEvent(
+  eventId: string,
+  kind: number,
+  pubkey: string,
+  reason?: string
+): UnsignedEvent {
+  const tags: string[][] = [
+    ['e', eventId],
+    ['k', String(kind)]
+  ]
+
+  return {
+    kind: EVENT_KINDS.DELETE,
+    pubkey,
+    created_at: Math.floor(Date.now() / 1000),
+    tags,
+    content: reason || ''
+  }
+}
+
+/**
+ * Build payment request DM content
+ */
+export function buildPaymentRequestContent(
+  order: Order,
+  invoice: string,
+  message?: string
+): NIP15PaymentRequest {
+  return {
+    id: order.id,
+    type: 1,
+    message: message || `Payment request for order ${order.id}. Total: ${order.total_sats} sats`,
+    payment_options: [
+      { type: 'ln', link: invoice }
+    ]
+  }
+}
+
+/**
+ * Build order status update DM content
+ */
+export function buildOrderStatusContent(
+  order: Order,
+  message: string
+): NIP15OrderStatusUpdate {
+  return {
+    id: order.id,
+    type: 2,
+    message,
+    paid: order.status !== 'pending',
+    shipped: order.status === 'shipped' || order.status === 'completed'
+  }
+}
+
+/**
+ * Build encrypted DM event (kind 4)
+ * Note: Actual encryption happens in the manager using NIP-44
+ */
+export function buildDirectMessageEvent(
+  content: string,  // Already encrypted
+  fromPubkey: string,
+  toPubkey: string
+): UnsignedEvent {
+  return {
+    kind: EVENT_KINDS.DIRECT_MESSAGE,
+    pubkey: fromPubkey,
+    created_at: Math.floor(Date.now() / 1000),
+    tags: [
+      ['p', toPubkey]
+    ],
+    content
+  }
+}
--- a/src/extensions/marketplace/nostr/kinds.ts
+++ b/src/extensions/marketplace/nostr/kinds.ts
@ -0,0 +1,31 @@
+/**
+ * NIP-15 Event Kinds
+ * https://github.com/nostr-protocol/nips/blob/master/15.md
+ */
+
+export const EVENT_KINDS = {
+  // Standard kinds
+  METADATA: 0,              // User profile
+  TEXT_NOTE: 1,             // Short text
+  DIRECT_MESSAGE: 4,        // Encrypted DM (NIP-04)
+  DELETE: 5,                // Event deletion
+
+  // NIP-15 Marketplace kinds
+  STALL: 30017,             // Parameterized replaceable: merchant stall
+  PRODUCT: 30018,           // Parameterized replaceable: product listing
+
+  // Lightning.Pub RPC kinds (for native clients)
+  RPC_REQUEST: 21001,       // Encrypted RPC request
+  RPC_RESPONSE: 21002,      // Encrypted RPC response
+} as const
+
+export type EventKind = typeof EVENT_KINDS[keyof typeof EVENT_KINDS]
+
+// Marketplace message types (in DM content)
+export const MESSAGE_TYPES = {
+  ORDER_REQUEST: 0,
+  PAYMENT_REQUEST: 1,
+  ORDER_STATUS: 2,
+} as const
+
+export type MessageTypeNum = typeof MESSAGE_TYPES[keyof typeof MESSAGE_TYPES]
--- a/src/extensions/marketplace/nostr/parser.ts
+++ b/src/extensions/marketplace/nostr/parser.ts
@ -0,0 +1,162 @@
+import { EVENT_KINDS, MESSAGE_TYPES } from './kinds.js'
+import {
+  NIP15Stall, NIP15Product, NIP15OrderRequest,
+  Stall, Product, MessageType
+} from '../types.js'
+import { generateId } from '../utils/validation.js'
+
+/**
+ * Nostr event structure
+ */
+export interface NostrEvent {
+  id: string
+  pubkey: string
+  created_at: number
+  kind: number
+  tags: string[][]
+  content: string
+  sig?: string
+}
+
+/**
+ * Parse NIP-15 stall event
+ */
+export function parseStallEvent(event: NostrEvent): Partial<Stall> | null {
+  if (event.kind !== EVENT_KINDS.STALL) return null
+
+  try {
+    const content = JSON.parse(event.content) as NIP15Stall
+    const dTag = event.tags.find(t => t[0] === 'd')
+
+    return {
+      id: content.id || dTag?.[1] || generateId(),
+      name: content.name,
+      description: content.description || '',
+      currency: content.currency as any || 'sat',
+      shipping_zones: (content.shipping || []).map(zone => ({
+        id: zone.id || generateId(),
+        name: zone.name || zone.id,
+        cost: zone.cost,
+        regions: zone.regions || []
+      })),
+      nostr_event_id: event.id,
+      nostr_event_created_at: event.created_at
+    }
+  } catch (e) {
+    return null
+  }
+}
+
+/**
+ * Parse NIP-15 product event
+ */
+export function parseProductEvent(event: NostrEvent): Partial<Product> | null {
+  if (event.kind !== EVENT_KINDS.PRODUCT) return null
+
+  try {
+    const content = JSON.parse(event.content) as NIP15Product
+    const dTag = event.tags.find(t => t[0] === 'd')
+    const categoryTags = event.tags.filter(t => t[0] === 't').map(t => t[1])
+
+    return {
+      id: content.id || dTag?.[1] || generateId(),
+      stall_id: content.stall_id,
+      name: content.name,
+      description: content.description || '',
+      images: content.images || [],
+      price: content.price,
+      quantity: content.quantity ?? -1,
+      categories: categoryTags.length > 0 ? categoryTags : [],
+      specs: content.specs?.map(([key, value]) => ({ key, value })),
+      nostr_event_id: event.id,
+      nostr_event_created_at: event.created_at
+    }
+  } catch (e) {
+    return null
+  }
+}
+
+/**
+ * Parse NIP-15 order request from DM
+ */
+export function parseOrderRequest(content: string): NIP15OrderRequest | null {
+  try {
+    const parsed = JSON.parse(content)
+    if (parsed.type !== MESSAGE_TYPES.ORDER_REQUEST) return null
+
+    return {
+      id: parsed.id || generateId(),
+      type: 0,
+      name: parsed.name,
+      address: parsed.address,
+      message: parsed.message,
+      contact: parsed.contact || {},
+      items: parsed.items || [],
+      shipping_id: parsed.shipping_id
+    }
+  } catch (e) {
+    return null
+  }
+}
+
+/**
+ * Determine message type from decrypted content
+ */
+export function parseMessageType(content: string): { type: MessageType; parsed: any } {
+  try {
+    const parsed = JSON.parse(content)
+
+    if (typeof parsed.type === 'number') {
+      switch (parsed.type) {
+        case MESSAGE_TYPES.ORDER_REQUEST:
+          return { type: 'order_request', parsed }
+        case MESSAGE_TYPES.PAYMENT_REQUEST:
+          return { type: 'payment_request', parsed }
+        case MESSAGE_TYPES.ORDER_STATUS:
+          return { type: 'order_status', parsed }
+      }
+    }
+
+    // If it has items and shipping_id, treat as order request
+    if (parsed.items && parsed.shipping_id) {
+      return { type: 'order_request', parsed: { ...parsed, type: 0 } }
+    }
+
+    return { type: 'plain', parsed: content }
+  } catch {
+    return { type: 'plain', parsed: content }
+  }
+}
+
+/**
+ * Extract pubkey from p tag
+ */
+export function extractRecipientPubkey(event: NostrEvent): string | null {
+  const pTag = event.tags.find(t => t[0] === 'p')
+  return pTag?.[1] || null
+}
+
+/**
+ * Check if event is a deletion event for a specific kind
+ */
+export function isDeletionEvent(event: NostrEvent, targetKind?: number): boolean {
+  if (event.kind !== EVENT_KINDS.DELETE) return false
+
+  if (targetKind !== undefined) {
+    const kTag = event.tags.find(t => t[0] === 'k')
+    return kTag?.[1] === String(targetKind)
+  }
+
+  return true
+}
+
+/**
+ * Get deleted event IDs from a deletion event
+ */
+export function getDeletedEventIds(event: NostrEvent): string[] {
+  if (event.kind !== EVENT_KINDS.DELETE) return []
+
+  return event.tags
+    .filter(t => t[0] === 'e')
+    .map(t => t[1])
+}
--- a/src/extensions/marketplace/types.ts
+++ b/src/extensions/marketplace/types.ts
@ -0,0 +1,418 @@
+/**
+ * Marketplace Extension Types
+ * NIP-15 compliant marketplace for Lightning.Pub
+ */
+
+// Re-export base extension types
+export {
+  Extension,
+  ExtensionInfo,
+  ExtensionContext,
+  ExtensionDatabase,
+  ApplicationInfo,
+  NostrEvent,
+  UnsignedNostrEvent,
+  PaymentReceivedData,
+  RpcMethodHandler
+} from '../types.js'
+
+// ============================================================================
+// Core Data Types
+// ============================================================================
+
+export interface ShippingZone {
+  id: string
+  name: string
+  cost: number          // In stall's currency
+  regions: string[]     // ISO country codes or region names
+}
+
+export interface Stall {
+  id: string
+  application_id: string
+  name: string
+  description: string
+  currency: Currency
+  shipping_zones: ShippingZone[]
+  image_url?: string
+
+  // Nostr sync
+  nostr_event_id?: string
+  nostr_event_created_at?: number
+
+  // Metadata
+  created_at: number
+  updated_at: number
+}
+
+export interface Product {
+  id: string
+  stall_id: string
+  application_id: string
+
+  name: string
+  description: string
+  images: string[]
+  price: number                 // In stall's currency
+  quantity: number              // Available stock (-1 = unlimited)
+  categories: string[]
+
+  // Shipping override (optional, otherwise use stall zones)
+  shipping_cost?: number
+
+  // Product options/variants (future)
+  specs?: ProductSpec[]
+
+  // Behavior
+  active: boolean
+
+  // Nostr sync
+  nostr_event_id?: string
+  nostr_event_created_at?: number
+
+  // Metadata
+  created_at: number
+  updated_at: number
+}
+
+export interface ProductSpec {
+  key: string
+  value: string
+}
+
+export interface OrderItem {
+  product_id: string
+  product_name: string        // Snapshot at order time
+  quantity: number
+  unit_price: number          // In stall currency, at order time
+}
+
+export interface ContactInfo {
+  nostr?: string              // Nostr pubkey
+  email?: string
+  phone?: string
+}
+
+export type OrderStatus =
+  | 'pending'                 // Awaiting payment
+  | 'paid'                    // Payment received
+  | 'processing'              // Merchant preparing
+  | 'shipped'                 // In transit
+  | 'completed'               // Delivered
+  | 'cancelled'               // Cancelled by merchant or customer
+
+export interface Order {
+  id: string
+  application_id: string
+  stall_id: string
+
+  // Customer
+  customer_pubkey: string     // Nostr pubkey
+  customer_app_user_id?: string  // If registered user
+
+  // Order details
+  items: OrderItem[]
+  shipping_zone_id: string
+  shipping_address: string
+  contact: ContactInfo
+
+  // Pricing (all in sats)
+  subtotal_sats: number
+  shipping_sats: number
+  total_sats: number
+
+  // Original currency info (for display)
+  original_currency: Currency
+  exchange_rate?: number      // Rate at order time
+
+  // Payment
+  invoice?: string            // BOLT11 invoice
+  invoice_id?: string         // Internal invoice reference
+
+  // Status
+  status: OrderStatus
+
+  // Nostr
+  nostr_event_id?: string     // Order request event
+
+  // Timestamps
+  created_at: number
+  paid_at?: number
+  shipped_at?: number
+  completed_at?: number
+}
+
+export interface DirectMessage {
+  id: string
+  application_id: string
+  order_id?: string           // Optional link to order
+
+  customer_pubkey: string
+
+  // Message content
+  message_type: MessageType
+  content: string             // Decrypted content
+
+  // Direction
+  incoming: boolean           // true = from customer, false = to customer
+
+  // Nostr
+  nostr_event_id: string
+  nostr_event_created_at: number
+
+  // Metadata
+  created_at: number
+  read: boolean
+}
+
+export type MessageType =
+  | 'plain'                   // Regular text message
+  | 'order_request'           // Customer order (type 0)
+  | 'payment_request'         // Merchant payment request (type 1)
+  | 'order_status'            // Order update (type 2)
+
+export interface Customer {
+  pubkey: string
+  application_id: string
+
+  // Profile (from kind 0)
+  name?: string
+  about?: string
+  picture?: string
+
+  // Stats
+  total_orders: number
+  total_spent_sats: number
+  unread_messages: number
+
+  // Metadata
+  first_seen_at: number
+  last_seen_at: number
+}
+
+// ============================================================================
+// Currency Types
+// ============================================================================
+
+export type Currency = 'sat' | 'btc' | 'usd' | 'eur' | 'gbp' | 'cad' | 'aud' | 'jpy'
+
+export interface ExchangeRate {
+  currency: Currency
+  rate_sats: number           // How many sats per 1 unit of currency
+  timestamp: number
+}
+
+// ============================================================================
+// NIP-15 Event Types
+// ============================================================================
+
+export interface NIP15Stall {
+  id: string
+  name: string
+  description?: string
+  currency: string
+  shipping: NIP15ShippingZone[]
+}
+
+export interface NIP15ShippingZone {
+  id: string
+  name?: string
+  cost: number
+  regions: string[]
+}
+
+export interface NIP15Product {
+  id: string
+  stall_id: string
+  name: string
+  description?: string
+  images?: string[]
+  currency: string
+  price: number
+  quantity: number
+  specs?: Array<[string, string]>
+  shipping?: NIP15ProductShipping[]
+}
+
+export interface NIP15ProductShipping {
+  id: string                  // Zone ID
+  cost: number
+}
+
+export interface NIP15OrderRequest {
+  id: string
+  type: 0
+  name?: string
+  address?: string
+  message?: string
+  contact: {
+    nostr?: string
+    phone?: string
+    email?: string
+  }
+  items: Array<{
+    product_id: string
+    quantity: number
+  }>
+  shipping_id: string
+}
+
+export interface NIP15PaymentRequest {
+  id: string
+  type: 1
+  message?: string
+  payment_options: Array<{
+    type: 'ln' | 'url' | 'btc'
+    link: string
+  }>
+}
+
+export interface NIP15OrderStatusUpdate {
+  id: string
+  type: 2
+  message: string
+  paid?: boolean
+  shipped?: boolean
+}
+
+// ============================================================================
+// RPC Request/Response Types
+// ============================================================================
+
+// Stall operations
+export interface CreateStallRequest {
+  name: string
+  description?: string
+  currency: Currency
+  shipping_zones: Array<Omit<ShippingZone, 'id'> & { id?: string }>
+  image_url?: string
+  publish_to_nostr?: boolean  // Default: true
+}
+
+export interface UpdateStallRequest {
+  stall_id: string
+  name?: string
+  description?: string
+  currency?: Currency
+  shipping_zones?: ShippingZone[]
+  image_url?: string
+  publish_to_nostr?: boolean  // Default: true
+}
+
+export interface GetStallRequest {
+  stall_id: string
+}
+
+export interface ListStallsRequest {
+  limit?: number
+  offset?: number
+}
+
+// Product operations
+export interface CreateProductRequest {
+  stall_id: string
+  name: string
+  description?: string
+  images?: string[]
+  price: number
+  quantity?: number            // Default: -1 (unlimited)
+  categories?: string[]
+  shipping_cost?: number
+  specs?: ProductSpec[]
+  active?: boolean
+  publish_to_nostr?: boolean   // Default: true
+}
+
+export interface UpdateProductRequest {
+  product_id: string
+  name?: string
+  description?: string
+  images?: string[]
+  price?: number
+  quantity?: number
+  categories?: string[]
+  shipping_cost?: number
+  specs?: ProductSpec[]
+  active?: boolean
+  publish_to_nostr?: boolean   // Default: true
+}
+
+export interface GetProductRequest {
+  product_id: string
+}
+
+export interface ListProductsRequest {
+  stall_id?: string
+  category?: string
+  active_only?: boolean
+  limit?: number
+  offset?: number
+}
+
+// Order operations
+export interface CreateOrderRequest {
+  stall_id: string
+  items: Array<{ product_id: string; quantity: number }>
+  shipping_zone_id: string
+  shipping_address: string
+  contact: ContactInfo
+}
+
+export interface GetOrderRequest {
+  order_id: string
+}
+
+export interface ListOrdersRequest {
+  stall_id?: string
+  status?: OrderStatus
+  customer_pubkey?: string
+  limit?: number
+  offset?: number
+}
+
+export interface UpdateOrderStatusRequest {
+  order_id: string
+  status: OrderStatus
+  message?: string
+}
+
+// Message operations
+export interface SendMessageRequest {
+  customer_pubkey: string
+  message: string
+  order_id?: string
+}
+
+export interface ListMessagesRequest {
+  customer_pubkey?: string
+  order_id?: string
+  unread_only?: boolean
+  limit?: number
+  offset?: number
+}
+
+export interface MarkMessagesReadRequest {
+  customer_pubkey?: string
+  message_ids?: string[]
+}
+
+// Customer operations
+export interface ListCustomersRequest {
+  limit?: number
+  offset?: number
+}
+
+export interface GetCustomerRequest {
+  pubkey: string
+}
+
+// ============================================================================
+// Extension Context Types
+// ============================================================================
+
+export interface MarketplaceContext {
+  application_id: string
+  application_pubkey: string
+  user_id: string
+  is_owner: boolean
+}
--- a/src/extensions/marketplace/utils/currency.ts
+++ b/src/extensions/marketplace/utils/currency.ts
@ -0,0 +1,205 @@
+import { ExtensionDatabase } from '../types.js'
+
+/**
+ * Exchange rate data
+ */
+interface ExchangeRateData {
+  currency: string
+  rate_sats: number  // How many sats per 1 unit of currency
+  updated_at: number
+}
+
+// Cache duration: 10 minutes
+const CACHE_DURATION_MS = 10 * 60 * 1000
+
+// In-memory cache for rates
+const rateCache = new Map<string, { rate: number; timestamp: number }>()
+
+/**
+ * Supported fiat currencies
+ */
+export const SUPPORTED_CURRENCIES = ['sat', 'btc', 'usd', 'eur', 'gbp', 'cad', 'aud', 'jpy'] as const
+export type SupportedCurrency = typeof SUPPORTED_CURRENCIES[number]
+
+/**
+ * Get exchange rate from cache or database
+ */
+async function getCachedRate(
+  db: ExtensionDatabase,
+  currency: string
+): Promise<number | null> {
+  // Check memory cache first
+  const cached = rateCache.get(currency)
+  if (cached && Date.now() - cached.timestamp < CACHE_DURATION_MS) {
+    return cached.rate
+  }
+
+  // Check database cache
+  const result = await db.query<ExchangeRateData>(
+    'SELECT * FROM exchange_rates WHERE currency = ?',
+    [currency]
+  )
+
+  if (result.length > 0) {
+    const row = result[0]
+    if (Date.now() - row.updated_at * 1000 < CACHE_DURATION_MS) {
+      rateCache.set(currency, { rate: row.rate_sats, timestamp: row.updated_at * 1000 })
+      return row.rate_sats
+    }
+  }
+
+  return null
+}
+
+/**
+ * Save exchange rate to cache and database
+ */
+async function saveRate(
+  db: ExtensionDatabase,
+  currency: string,
+  rateSats: number
+): Promise<void> {
+  const now = Math.floor(Date.now() / 1000)
+
+  // Save to memory cache
+  rateCache.set(currency, { rate: rateSats, timestamp: now * 1000 })
+
+  // Save to database (upsert)
+  await db.execute(
+    `INSERT INTO exchange_rates (currency, rate_sats, updated_at)
+     VALUES (?, ?, ?)
+     ON CONFLICT(currency) DO UPDATE SET
+       rate_sats = excluded.rate_sats,
+       updated_at = excluded.updated_at`,
+    [currency, rateSats, now]
+  )
+}
+
+/**
+ * Fetch current BTC price from public API
+ * Returns price in USD per BTC
+ */
+async function fetchBtcPrice(): Promise<number> {
+  // Try CoinGecko first (free, no API key)
+  try {
+    const response = await fetch(
+      'https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd,eur,gbp,cad,aud,jpy'
+    )
+    if (response.ok) {
+      const data = await response.json()
+      return data.bitcoin.usd
+    }
+  } catch (e) {
+    // Fall through to backup
+  }
+
+  // Backup: use a hardcoded fallback (should be updated periodically)
+  // This is a safety net - in production you'd want multiple API sources
+  console.warn('Failed to fetch exchange rate, using fallback')
+  return 100000  // Fallback BTC price in USD
+}
+
+/**
+ * Get exchange rate: sats per 1 unit of currency
+ */
+export async function getExchangeRate(
+  db: ExtensionDatabase,
+  currency: SupportedCurrency
+): Promise<number> {
+  // Bitcoin denominations are fixed
+  if (currency === 'sat') return 1
+  if (currency === 'btc') return 100_000_000
+
+  // Check cache
+  const cached = await getCachedRate(db, currency)
+  if (cached !== null) return cached
+
+  // Fetch fresh rate
+  const btcPriceUsd = await fetchBtcPrice()
+  const satsPerBtc = 100_000_000
+
+  // Calculate rates for all fiat currencies
+  // Using approximate cross-rates (in production, fetch all from API)
+  const usdRates: Record<string, number> = {
+    usd: 1,
+    eur: 0.92,
+    gbp: 0.79,
+    cad: 1.36,
+    aud: 1.53,
+    jpy: 149.5
+  }
+
+  // Calculate sats per 1 unit of each currency
+  for (const [curr, usdRate] of Object.entries(usdRates)) {
+    const priceInCurrency = btcPriceUsd * usdRate
+    const satsPerUnit = Math.round(satsPerBtc / priceInCurrency)
+    await saveRate(db, curr, satsPerUnit)
+  }
+
+  // Return requested currency rate
+  const rate = await getCachedRate(db, currency)
+  return rate || 1  // Fallback to 1:1 if something went wrong
+}
+
+/**
+ * Convert amount from a currency to sats
+ */
+export async function convertToSats(
+  db: ExtensionDatabase,
+  amount: number,
+  currency: SupportedCurrency
+): Promise<number> {
+  if (currency === 'sat') return Math.round(amount)
+
+  const rate = await getExchangeRate(db, currency)
+  return Math.round(amount * rate)
+}
+
+/**
+ * Convert amount from sats to a currency
+ */
+export async function convertFromSats(
+  db: ExtensionDatabase,
+  sats: number,
+  currency: SupportedCurrency
+): Promise<number> {
+  if (currency === 'sat') return sats
+
+  const rate = await getExchangeRate(db, currency)
+  return sats / rate
+}
+
+/**
+ * Format amount with currency symbol
+ */
+export function formatCurrency(amount: number, currency: SupportedCurrency): string {
+  const symbols: Record<SupportedCurrency, string> = {
+    sat: ' sats',
+    btc: ' BTC',
+    usd: '$',
+    eur: '€',
+    gbp: '£',
+    cad: 'CA$',
+    aud: 'AU$',
+    jpy: '¥'
+  }
+
+  const symbol = symbols[currency]
+  const isPrefix = ['usd', 'gbp', 'cad', 'aud', 'jpy'].includes(currency)
+
+  if (currency === 'btc') {
+    return `${amount.toFixed(8)}${symbol}`
+  }
+
+  if (currency === 'sat') {
+    return `${amount.toLocaleString()}${symbol}`
+  }
+
+  // Fiat currencies
+  const formatted = amount.toLocaleString(undefined, {
+    minimumFractionDigits: 2,
+    maximumFractionDigits: 2
+  })
+
+  return isPrefix ? `${symbol}${formatted}` : `${formatted}${symbol}`
+}
--- a/src/extensions/marketplace/utils/validation.ts
+++ b/src/extensions/marketplace/utils/validation.ts
@ -0,0 +1,109 @@
+import crypto from 'crypto'
+import { CreateStallRequest, CreateProductRequest } from '../types.js'
+
+/**
+ * Generate a random ID
+ */
+export function generateId(): string {
+  return crypto.randomBytes(16).toString('hex')
+}
+
+/**
+ * Validate stall creation request
+ */
+export function validateStall(req: CreateStallRequest): void {
+  if (!req.name || req.name.trim().length === 0) {
+    throw new Error('Stall name is required')
+  }
+
+  if (req.name.length > 100) {
+    throw new Error('Stall name must be 100 characters or less')
+  }
+
+  const validCurrencies = ['sat', 'btc', 'usd', 'eur', 'gbp', 'cad', 'aud', 'jpy']
+  if (!validCurrencies.includes(req.currency)) {
+    throw new Error(`Invalid currency. Must be one of: ${validCurrencies.join(', ')}`)
+  }
+
+  if (!req.shipping_zones || req.shipping_zones.length === 0) {
+    throw new Error('At least one shipping zone is required')
+  }
+
+  for (const zone of req.shipping_zones) {
+    if (!zone.name || zone.name.trim().length === 0) {
+      throw new Error('Shipping zone name is required')
+    }
+    if (zone.cost < 0) {
+      throw new Error('Shipping cost cannot be negative')
+    }
+    if (!zone.regions || zone.regions.length === 0) {
+      throw new Error('Shipping zone must have at least one region')
+    }
+  }
+}
+
+/**
+ * Validate product creation request
+ */
+export function validateProduct(req: CreateProductRequest): void {
+  if (!req.name || req.name.trim().length === 0) {
+    throw new Error('Product name is required')
+  }
+
+  if (req.name.length > 200) {
+    throw new Error('Product name must be 200 characters or less')
+  }
+
+  if (req.price < 0) {
+    throw new Error('Price cannot be negative')
+  }
+
+  if (req.quantity < -1) {
+    throw new Error('Quantity must be -1 (unlimited) or >= 0')
+  }
+
+  if (req.images && req.images.length > 10) {
+    throw new Error('Maximum 10 images allowed')
+  }
+
+  if (req.categories && req.categories.length > 10) {
+    throw new Error('Maximum 10 categories allowed')
+  }
+}
+
+/**
+ * Validate Nostr pubkey format (64 char hex)
+ */
+export function validatePubkey(pubkey: string): boolean {
+  return /^[0-9a-f]{64}$/i.test(pubkey)
+}
+
+/**
+ * Sanitize string input
+ */
+export function sanitizeString(input: string, maxLength: number = 1000): string {
+  if (!input) return ''
+  return input.trim().slice(0, maxLength)
+}
+
+/**
+ * Validate order items
+ */
+export function validateOrderItems(items: Array<{ product_id: string; quantity: number }>): void {
+  if (!items || items.length === 0) {
+    throw new Error('Order must have at least one item')
+  }
+
+  if (items.length > 100) {
+    throw new Error('Maximum 100 items per order')
+  }
+
+  for (const item of items) {
+    if (!item.product_id) {
+      throw new Error('Product ID is required for each item')
+    }
+    if (!Number.isInteger(item.quantity) || item.quantity < 1) {
+      throw new Error('Quantity must be a positive integer')
+    }
+  }
+}
--- a/src/extensions/types.ts
+++ b/src/extensions/types.ts
@ -0,0 +1,254 @@
+/**
+ * Extension System Core Types
+ *
+ * These types define the contract between Lightning.Pub and extensions.
+ */
+
+/**
+ * Extension metadata
+ */
+export interface ExtensionInfo {
+  id: string                    // Unique identifier (lowercase, no spaces)
+  name: string                  // Display name
+  version: string               // Semver version
+  description: string           // Short description
+  author: string                // Author name or organization
+  minPubVersion?: string        // Minimum Lightning.Pub version required
+  dependencies?: string[]       // Other extension IDs this depends on
+}
+
+/**
+ * Extension database interface
+ * Provides isolated database access for each extension
+ */
+export interface ExtensionDatabase {
+  /**
+   * Execute a write query (INSERT, UPDATE, DELETE, CREATE, etc.)
+   */
+  execute(sql: string, params?: any[]): Promise<{ changes?: number; lastId?: number }>
+
+  /**
+   * Execute a read query (SELECT)
+   */
+  query<T = any>(sql: string, params?: any[]): Promise<T[]>
+
+  /**
+   * Execute multiple statements in a transaction
+   */
+  transaction<T>(fn: () => Promise<T>): Promise<T>
+}
+
+/**
+ * Application info provided to extensions
+ */
+export interface ApplicationInfo {
+  id: string
+  name: string
+  nostr_public: string          // Application's Nostr pubkey (hex)
+  balance_sats: number
+}
+
+/**
+ * Invoice creation options
+ */
+export interface CreateInvoiceOptions {
+  memo?: string
+  expiry?: number               // Seconds until expiry
+  metadata?: Record<string, any>  // Custom metadata for callbacks
+}
+
+/**
+ * Created invoice result
+ */
+export interface CreatedInvoice {
+  id: string                    // Internal invoice ID
+  paymentRequest: string        // BOLT11 invoice string
+  paymentHash: string           // Payment hash (hex)
+  expiry: number                // Expiry timestamp
+}
+
+/**
+ * Payment received callback data
+ */
+export interface PaymentReceivedData {
+  invoiceId: string
+  paymentHash: string
+  amountSats: number
+  metadata?: Record<string, any>
+}
+
+/**
+ * LNURL-pay info response (LUD-06/LUD-16)
+ * Used for Lightning Address and zap support
+ */
+export interface LnurlPayInfo {
+  tag: 'payRequest'
+  callback: string                // URL to call with amount
+  minSendable: number             // Minimum msats
+  maxSendable: number             // Maximum msats
+  metadata: string                // JSON-encoded metadata array
+  allowsNostr?: boolean           // Whether zaps are supported
+  nostrPubkey?: string            // Pubkey for zap receipts (hex)
+}
+
+/**
+ * Nostr event structure (minimal)
+ */
+export interface NostrEvent {
+  id: string
+  pubkey: string
+  created_at: number
+  kind: number
+  tags: string[][]
+  content: string
+  sig?: string
+}
+
+/**
+ * Unsigned Nostr event for publishing
+ */
+export interface UnsignedNostrEvent {
+  kind: number
+  pubkey: string
+  created_at: number
+  tags: string[][]
+  content: string
+}
+
+/**
+ * RPC method handler function
+ */
+export type RpcMethodHandler = (
+  request: any,
+  applicationId: string,
+  userPubkey?: string
+) => Promise<any>
+
+/**
+ * Extension context - interface provided to extensions for interacting with Lightning.Pub
+ */
+export interface ExtensionContext {
+  /**
+   * Get information about an application
+   */
+  getApplication(applicationId: string): Promise<ApplicationInfo | null>
+
+  /**
+   * Create a Lightning invoice
+   */
+  createInvoice(amountSats: number, options?: CreateInvoiceOptions): Promise<CreatedInvoice>
+
+  /**
+   * Pay a Lightning invoice (requires sufficient balance)
+   */
+  payInvoice(applicationId: string, paymentRequest: string, maxFeeSats?: number): Promise<{
+    paymentHash: string
+    feeSats: number
+  }>
+
+  /**
+   * Send an encrypted DM via Nostr (NIP-44)
+   */
+  sendEncryptedDM(applicationId: string, recipientPubkey: string, content: string): Promise<string>
+
+  /**
+   * Publish a Nostr event (signed by application's key)
+   */
+  publishNostrEvent(event: UnsignedNostrEvent): Promise<string | null>
+
+  /**
+   * Get LNURL-pay info for a user (by pubkey)
+   * Used to enable Lightning Address support (LUD-16) and zaps (NIP-57)
+   */
+  getLnurlPayInfo(pubkeyHex: string, options?: {
+    metadata?: string              // Custom metadata JSON
+    description?: string           // Human-readable description
+  }): Promise<LnurlPayInfo>
+
+  /**
+   * Subscribe to payment received callbacks
+   */
+  onPaymentReceived(callback: (payment: PaymentReceivedData) => Promise<void>): void
+
+  /**
+   * Subscribe to incoming Nostr events for the application
+   */
+  onNostrEvent(callback: (event: NostrEvent, applicationId: string) => Promise<void>): void
+
+  /**
+   * Register an RPC method
+   */
+  registerMethod(name: string, handler: RpcMethodHandler): void
+
+  /**
+   * Get the extension's isolated database
+   */
+  getDatabase(): ExtensionDatabase
+
+  /**
+   * Log a message (prefixed with extension ID)
+   */
+  log(level: 'debug' | 'info' | 'warn' | 'error', message: string, ...args: any[]): void
+}
+
+/**
+ * Extension interface - what extensions must implement
+ */
+export interface Extension {
+  /**
+   * Extension metadata
+   */
+  readonly info: ExtensionInfo
+
+  /**
+   * Initialize the extension
+   * Called once when the extension is loaded
+   */
+  initialize(ctx: ExtensionContext, db: ExtensionDatabase): Promise<void>
+
+  /**
+   * Shutdown the extension
+   * Called when Lightning.Pub is shutting down
+   */
+  shutdown?(): Promise<void>
+
+  /**
+   * Health check
+   * Return true if extension is healthy
+   */
+  healthCheck?(): Promise<boolean>
+}
+
+/**
+ * Extension constructor type
+ */
+export type ExtensionConstructor = new () => Extension
+
+/**
+ * Extension module default export
+ */
+export interface ExtensionModule {
+  default: ExtensionConstructor
+}
+
+/**
+ * Loaded extension state
+ */
+export interface LoadedExtension {
+  info: ExtensionInfo
+  instance: Extension
+  database: ExtensionDatabase
+  status: 'loading' | 'ready' | 'error' | 'stopped'
+  error?: Error
+  loadedAt: number
+}
+
+/**
+ * Extension loader configuration
+ */
+export interface ExtensionLoaderConfig {
+  extensionsDir: string         // Directory containing extensions
+  databaseDir: string           // Directory for extension databases
+  enabledExtensions?: string[]  // If set, only load these extensions
+  disabledExtensions?: string[] // Extensions to skip
+}
--- a/src/nostrMiddleware.ts
+++ b/src/nostrMiddleware.ts
@ -105,7 +105,7 @@ export default (serverMethods: Types.ServerMethods, mainHandler: Main, nostrSett

    return {
        Stop: () => { mainHandler.adminManager.setNostrConnected(false); return nostr.Stop },
-        Send: (...args) => nostr.Send(...args),
+        Send: async (...args) => nostr.Send(...args),
        Ping: () => nostr.Ping(),
        Reset: (settings: NostrSettings) => nostr.Reset(settings)
    }
--- a/src/services/main/debitManager.ts
+++ b/src/services/main/debitManager.ts
@ -153,13 +153,14 @@ export class DebitManager {
    }

    notifyPaymentSuccess = (debitRes: NdebitSuccess, event: { pub: string, id: string, appId: string }) => {
+        this.logger("✅ [DEBIT REQUEST] Payment successful, sending OK response to", event.pub.slice(0, 16) + "...", "for event", event.id.slice(0, 16) + "...")
        this.sendDebitResponse(debitRes, event)
    }

    sendDebitResponse = (debitRes: NdebitFailure | NdebitSuccess, event: { pub: string, id: string, appId: string }) => {
+        this.logger("📤 [DEBIT RESPONSE] Sending Kind 21002 response:", JSON.stringify(debitRes), "to", event.pub.slice(0, 16) + "...")
        const e = newNdebitResponse(JSON.stringify(debitRes), event)
        this.storage.NostrSender().Send({ type: 'app', appId: event.appId }, { type: 'event', event: e, encrypt: { toPub: event.pub } })
-
    }

    payNdebitInvoice = async (event: NostrEvent, pointerdata: NdebitData): Promise<HandleNdebitRes> => {
--- a/src/services/nostr/handler.ts
+++ b/src/services/nostr/handler.ts
@ -132,12 +132,12 @@ const handleNostrSettings = (settings: NostrSettings) => {
        send(event)
    })
 } */
-const sendToNostr: NostrSend = (initiator, data, relays) => {
+const sendToNostr: NostrSend = async (initiator, data, relays) => {
    if (!subProcessHandler) {
        getLogger({ component: "nostrMiddleware" })(ERROR, "nostr was not initialized")
        return
    }
-    subProcessHandler.Send(initiator, data, relays)
+    await subProcessHandler.Send(initiator, data, relays)
 }

 send({ type: 'ready' })
--- a/src/services/nostr/nostrPool.ts
+++ b/src/services/nostr/nostrPool.ts
@ -16,7 +16,7 @@ export type SendDataContent = { type: "content", content: string, pub: string }
 export type SendDataEvent = { type: "event", event: UnsignedEvent, encrypt?: { toPub: string } }
 export type SendData = SendDataContent | SendDataEvent
 export type SendInitiator = { type: 'app', appId: string } | { type: 'client', clientId: string }
-export type NostrSend = (initiator: SendInitiator, data: SendData, relays?: string[] | undefined) => void
+export type NostrSend = (initiator: SendInitiator, data: SendData, relays?: string[] | undefined) => Promise<void>

 export type LinkedProviderInfo = { pubkey: string, clientId: string, relayUrl: string }
 export type AppInfo = { appId: string, publicKey: string, privateKey: string, name: string, provider?: LinkedProviderInfo }
@ -203,21 +203,22 @@ export class NostrPool {
        const signed = finalizeEvent(event, Buffer.from(keys.privateKey, 'hex'))
        let sent = false
        const log = getLogger({ appName: keys.name })
-        // const r = relays ? relays : this.getServiceRelays()
+        this.log(`📤 Publishing Kind ${event.kind} event to ${relays.length} relay(s): ${relays.join(', ')}`)
        const pool = new SimplePool()
        await Promise.all(pool.publish(relays, signed).map(async p => {
            try {
                await p
                sent = true
            } catch (e: any) {
-                console.log(e)
+                this.log(ERROR, `Failed to publish Kind ${event.kind} event:`, e.message || e)
                log(e)
            }
        }))
        if (!sent) {
+            this.log(ERROR, `Failed to send Kind ${event.kind} event to any relay`)
            log("failed to send event")
        } else {
-            //log("sent event")
+            this.log(`✅ Kind ${event.kind} event published successfully (id: ${signed.id.slice(0, 16)}...)`)
        }
    }

--- a/src/services/nostr/sender.ts
+++ b/src/services/nostr/sender.ts
@ -1,7 +1,7 @@
 import { NostrSend, SendData, SendInitiator } from "./nostrPool.js"
-import { getLogger } from "../helpers/logger.js"
+import { ERROR, getLogger } from "../helpers/logger.js"
 export class NostrSender {
-    private _nostrSend: NostrSend = () => { throw new Error('nostr send not initialized yet') }
+    private _nostrSend: NostrSend = async () => { throw new Error('nostr send not initialized yet') }
    private isReady: boolean = false
    private onReadyCallbacks: (() => void)[] = []
    private pendingSends: { initiator: SendInitiator, data: SendData, relays?: string[] | undefined }[] = []
@ -12,7 +12,12 @@ export class NostrSender {
        this.isReady = true
        this.onReadyCallbacks.forEach(cb => cb())
        this.onReadyCallbacks = []
-        this.pendingSends.forEach(send => this._nostrSend(send.initiator, send.data, send.relays))
+        // Process pending sends with proper error handling
+        this.pendingSends.forEach(send => {
+            this._nostrSend(send.initiator, send.data, send.relays).catch(e => {
+                this.log(ERROR, "failed to send pending event", e.message || e)
+            })
+        })
        this.pendingSends = []
    }
    OnReady(callback: () => void) {
@ -22,13 +27,16 @@ export class NostrSender {
            this.onReadyCallbacks.push(callback)
        }
    }
-    Send(initiator: SendInitiator, data: SendData, relays?: string[] | undefined) {
+    Send(initiator: SendInitiator, data: SendData, relays?: string[] | undefined): void {
        if (!this.isReady) {
            this.log("tried to send before nostr was ready, caching request")
            this.pendingSends.push({ initiator, data, relays })
            return
        }
-        this._nostrSend(initiator, data, relays)
+        // Fire and forget but log errors
+        this._nostrSend(initiator, data, relays).catch(e => {
+            this.log(ERROR, "failed to send event", e.message || e)
+        })
    }
    IsReady() {
        return this.isReady
--- a/src/services/storage/tlv/tlvFilesStorageProcessor.ts
+++ b/src/services/storage/tlv/tlvFilesStorageProcessor.ts
@ -126,7 +126,7 @@ class TlvFilesStorageProcessor {
                    throw new Error('Unknown metric type: ' + t)
            }
        })
-        this.wrtc.attachNostrSend((initiator: SendInitiator, data: SendData, relays?: string[] | undefined) => {
+        this.wrtc.attachNostrSend(async (initiator: SendInitiator, data: SendData, relays?: string[] | undefined) => {
            this.sendResponse({
                success: true,
                type: 'nostrSend',
--- a/src/services/webRTC/index.ts
+++ b/src/services/webRTC/index.ts
@ -27,11 +27,11 @@ export default class webRTC {
    attachNostrSend(f: NostrSend) {
        this._nostrSend = f
    }
-    private nostrSend: NostrSend = (initiator: SendInitiator, data: SendData, relays?: string[] | undefined) => {
+    private nostrSend: NostrSend = async (initiator: SendInitiator, data: SendData, relays?: string[] | undefined) => {
        if (!this._nostrSend) {
            throw new Error("No nostrSend attached")
        }
-        this._nostrSend(initiator, data, relays)
+        await this._nostrSend(initiator, data, relays)
    }

    private sendCandidate = (u: WebRtcUserInfo, candidate: string) => {
Author	SHA1	Message	Date
Patrick Mulligan	b5d81bcf30	feat(extensions): add NIP-15 marketplace extension Some checks failed Docker Compose Actions Workflow / test (push) Has been cancelled Details Implements a Nostr-native marketplace extension for Lightning.Pub that is compatible with NIP-15 (Nostr Marketplace). Features: - Stall management (kind 30017 events) - Product listings (kind 30018 events) - Order processing via encrypted Nostr DMs or RPC - Multi-currency support with exchange rate caching - Inventory management with stock tracking - Customer relationship management - Lightning payment integration The extension leverages Lightning.Pub's existing Nostr infrastructure for a more elegant implementation than traditional HTTP-based approaches. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>	2026-03-04 15:21:57 -05:00
Patrick Mulligan	e366fc607a	feat(extensions): add getLnurlPayInfo to ExtensionContext Enables extensions to get LNURL-pay info for users by pubkey, supporting Lightning Address (LUD-16) and zap (NIP-57) functionality. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>	2026-03-04 15:21:57 -05:00
Patrick Mulligan	af31f12cb9	docs(extensions): add comprehensive extension loader documentation Covers architecture, API reference, lifecycle, database isolation, RPC methods, HTTP routes, event handling, and complete examples. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>	2026-03-04 15:21:57 -05:00
Patrick Mulligan	70096ccfa5	feat(extensions): add extension loader infrastructure Adds a modular extension system for Lightning.Pub that allows third-party functionality to be added without modifying core code. Features: - ExtensionLoader: discovers and loads extensions from directory - ExtensionContext: provides extensions with access to Lightning.Pub APIs - ExtensionDatabase: isolated SQLite database per extension - Lifecycle management: initialize, shutdown, health checks - RPC method registration: extensions can add new RPC methods - Event dispatching: routes payments and Nostr events to extensions Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>	2026-03-04 15:21:57 -05:00
Patrick Mulligan	56e024cd93	fix(handlers): await NostrSend calls throughout codebase Update all NostrSend call sites to properly handle the async nature of the function now that it returns Promise<void>. Changes: - handler.ts: Add async to sendResponse, await nostrSend calls - debitManager.ts: Add logging for Kind 21002 response sending - nostrMiddleware.ts: Update nostrSend signature - tlvFilesStorageProcessor.ts: Update nostrSend signature - webRTC/index.ts: Add async/await for nostrSend calls This ensures Kind 21002 (ndebit) responses are properly sent to wallet clients, fixing the "Debit request failed" issue in ShockWallet. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>	2026-03-04 15:21:57 -05:00
Patrick Mulligan	44f8d4192f	fix(nostr): update NostrSend type to Promise<void> with error handling The NostrSend type was incorrectly typed as returning void when it actually returns Promise<void>. This caused async errors to be silently swallowed. Changes: - Update NostrSend type signature to return Promise<void> - Make NostrSender._nostrSend default to async function - Add .catch() error handling in NostrSender.Send() to log failures - Add logging to track event publishing status Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>	2026-03-04 15:21:57 -05:00