diff --git a/lamassu-next/packages/lightning/src/__tests__/client.test.ts b/lamassu-next/packages/lightning/src/__tests__/client.test.ts
new file mode 100644
index 0000000..764c79b
--- /dev/null
+++ b/lamassu-next/packages/lightning/src/__tests__/client.test.ts
@@ -0,0 +1,66 @@
+import { describe, it, expect, vi } from 'vitest'
+import { LightningPubClient } from '../client.js'
+
+describe('LightningPubClient', () => {
+  const config = {
+    serviceUrl: 'https://lightning.pub',
+    accountPubkey: 'a'.repeat(64),
+    relays: ['wss://relay.example.com'],
+  }
+
+  describe('constructor', () => {
+    it('should create a client with config', () => {
+      const client = new LightningPubClient(config)
+      expect(client).toBeDefined()
+    })
+  })
+
+  describe('getExchangeRate', () => {
+    it('should return mock exchange rate for USD', async () => {
+      const client = new LightningPubClient(config)
+      const rate = await client.getExchangeRate('USD')
+
+      expect(rate.currency).toBe('USD')
+      expect(rate.satsPerUnit).toBeGreaterThan(0)
+      expect(rate.timestamp).toBeDefined()
+    })
+
+    it('should return rate for different currencies', async () => {
+      const client = new LightningPubClient(config)
+
+      const usdRate = await client.getExchangeRate('USD')
+      const eurRate = await client.getExchangeRate('EUR')
+
+      expect(usdRate.satsPerUnit).not.toBe(eurRate.satsPerUnit)
+    })
+  })
+
+  describe('decodeInvoice', () => {
+    it('should decode a basic invoice', () => {
+      const client = new LightningPubClient(config)
+
+      // This is a simplified test since we have basic parsing
+      const result = client.decodeInvoice('lnbc100u1...')
+
+      expect(result).toBeDefined()
+      expect(result.expiresAt).toBeGreaterThan(Date.now() / 1000)
+    })
+  })
+
+  describe('initialize', () => {
+    it('should require nostrClient and identity', () => {
+      const client = new LightningPubClient(config)
+
+      // Without initialization, operations should fail
+      expect(client.getBalance()).rejects.toThrow('Client not initialized')
+    })
+  })
+
+  describe('disconnect', () => {
+    it('should clean up resources', () => {
+      const client = new LightningPubClient(config)
+      // Should not throw
+      expect(() => client.disconnect()).not.toThrow()
+    })
+  })
+})
diff --git a/lamassu-next/packages/lightning/src/client.ts b/lamassu-next/packages/lightning/src/client.ts
new file mode 100644
index 0000000..e892950
--- /dev/null
+++ b/lamassu-next/packages/lightning/src/client.ts
@@ -0,0 +1,405 @@
+/**
+ * Lightning.Pub Client
+ *
+ * Client for interacting with Lightning.Pub - a Nostr-native
+ * account system that wraps LND.
+ *
+ * Lightning.Pub provides:
+ * - Account management (sublayers)
+ * - Invoice generation
+ * - Payment processing
+ * - CLINK protocol support
+ */
+
+import type { Event } from 'nostr-tools'
+import { finalizeEvent } from 'nostr-tools'
+import type { MachineIdentity, NostrClient } from '@lamassu/nostr-client'
+import { encryptContent, decryptJSON } from '@lamassu/nostr-client'
+import type {
+  LightningPubConfig,
+  AccountInfo,
+  Invoice,
+  PaymentResult,
+  ExchangeRate,
+  InvoiceCallback,
+} from './types.js'
+
+/** Event kinds for Lightning.Pub communication */
+const LIGHTNING_PUB_KINDS = {
+  REQUEST: 23194, // NIP-47 compatible
+  RESPONSE: 23195,
+}
+
+/** Request types */
+type RequestMethod =
+  | 'get_info'
+  | 'get_balance'
+  | 'make_invoice'
+  | 'pay_invoice'
+  | 'lookup_invoice'
+  | 'list_transactions'
+
+interface Request {
+  method: RequestMethod
+  params: Record<string, unknown>
+}
+
+interface Response<T = unknown> {
+  result?: T
+  error?: { code: number; message: string }
+}
+
+/**
+ * Lightning.Pub client for ATM operations
+ */
+export class LightningPubClient {
+  private config: Required<LightningPubConfig>
+  private nostrClient: NostrClient | null = null
+  private identity: MachineIdentity | null = null
+  private invoiceCallbacks: Map<string, InvoiceCallback> = new Map()
+  private subscriptionId?: string
+
+  constructor(config: LightningPubConfig) {
+    this.config = {
+      timeout: 30000,
+      ...config,
+    }
+  }
+
+  /**
+   * Initialize the client with Nostr connection
+   */
+  initialize(nostrClient: NostrClient, identity: MachineIdentity): void {
+    this.nostrClient = nostrClient
+    this.identity = identity
+    this.startListening()
+  }
+
+  /**
+   * Get account information
+   */
+  async getAccountInfo(): Promise<AccountInfo> {
+    const response = await this.sendRequest<AccountInfo>({
+      method: 'get_info',
+      params: {},
+    })
+
+    return response
+  }
+
+  /**
+   * Get current balance
+   */
+  async getBalance(): Promise<{ balanceSats: number }> {
+    const response = await this.sendRequest<{ balance: number }>({
+      method: 'get_balance',
+      params: {},
+    })
+
+    return { balanceSats: response.balance }
+  }
+
+  /**
+   * Create a Lightning invoice
+   */
+  async createInvoice(params: {
+    amountMsat: number
+    description?: string
+    expirySecs?: number
+  }): Promise<Invoice> {
+    const response = await this.sendRequest<{
+      payment_request: string
+      payment_hash: string
+      expires_at: number
+    }>({
+      method: 'make_invoice',
+      params: {
+        amount: params.amountMsat,
+        description: params.description || 'ATM Payment',
+        expiry: params.expirySecs || 600,
+      },
+    })
+
+    return {
+      paymentRequest: response.payment_request,
+      paymentHash: response.payment_hash,
+      amountMsat: params.amountMsat,
+      description: params.description,
+      createdAt: Math.floor(Date.now() / 1000),
+      expiresAt: response.expires_at,
+      status: 'pending',
+    }
+  }
+
+  /**
+   * Pay a Lightning invoice
+   */
+  async payInvoice(paymentRequest: string): Promise<PaymentResult> {
+    try {
+      const response = await this.sendRequest<{
+        preimage: string
+        fee_paid?: number
+      }>({
+        method: 'pay_invoice',
+        params: {
+          invoice: paymentRequest,
+        },
+      })
+
+      return {
+        success: true,
+        preimage: response.preimage,
+        feeMsat: response.fee_paid,
+      }
+    } catch (error) {
+      return {
+        success: false,
+        error: error instanceof Error ? error.message : 'Payment failed',
+      }
+    }
+  }
+
+  /**
+   * Look up an invoice by payment hash
+   */
+  async lookupInvoice(paymentHash: string): Promise<Invoice | null> {
+    try {
+      const response = await this.sendRequest<{
+        payment_request: string
+        amount: number
+        description: string
+        created_at: number
+        expires_at: number
+        settled: boolean
+        preimage?: string
+      }>({
+        method: 'lookup_invoice',
+        params: {
+          payment_hash: paymentHash,
+        },
+      })
+
+      return {
+        paymentRequest: response.payment_request,
+        paymentHash,
+        amountMsat: response.amount,
+        description: response.description,
+        createdAt: response.created_at,
+        expiresAt: response.expires_at,
+        status: response.settled ? 'paid' : 'pending',
+        preimage: response.preimage,
+      }
+    } catch {
+      return null
+    }
+  }
+
+  /**
+   * Watch for invoice payment
+   */
+  watchInvoice(paymentHash: string, callback: InvoiceCallback): void {
+    this.invoiceCallbacks.set(paymentHash, callback)
+
+    // Poll for payment status
+    const pollInterval = setInterval(async () => {
+      const invoice = await this.lookupInvoice(paymentHash)
+      if (invoice && invoice.status === 'paid') {
+        clearInterval(pollInterval)
+        this.invoiceCallbacks.delete(paymentHash)
+        callback(invoice)
+      }
+    }, 2000)
+
+    // Clean up after expiry
+    setTimeout(
+      () => {
+        clearInterval(pollInterval)
+        this.invoiceCallbacks.delete(paymentHash)
+      },
+      10 * 60 * 1000
+    ) // 10 minutes max
+  }
+
+  /**
+   * Stop watching an invoice
+   */
+  unwatchInvoice(paymentHash: string): void {
+    this.invoiceCallbacks.delete(paymentHash)
+  }
+
+  /**
+   * Decode a BOLT11 invoice
+   */
+  decodeInvoice(paymentRequest: string): {
+    amountMsat: number | null
+    paymentHash: string
+    description: string
+    expiresAt: number
+  } {
+    // Basic invoice parsing (for production, use bolt11 library)
+    // This is a simplified version
+    const amountMatch = paymentRequest.match(/lnbc(\d+)([munp]?)/)
+    let amountMsat: number | null = null
+
+    if (amountMatch) {
+      const [, amount, multiplier] = amountMatch
+      const baseAmount = parseInt(amount ?? '0', 10)
+      switch (multiplier) {
+        case 'm':
+          amountMsat = baseAmount * 100_000_000
+          break
+        case 'u':
+          amountMsat = baseAmount * 100_000
+          break
+        case 'n':
+          amountMsat = baseAmount * 100
+          break
+        case 'p':
+          amountMsat = baseAmount / 10
+          break
+        default:
+          amountMsat = baseAmount * 100_000_000_000
+      }
+    }
+
+    return {
+      amountMsat,
+      paymentHash: '', // Would need proper parsing
+      description: '',
+      expiresAt: Math.floor(Date.now() / 1000) + 3600,
+    }
+  }
+
+  /**
+   * Get exchange rate (via external service or Lightning.Pub)
+   */
+  async getExchangeRate(currency: string): Promise<ExchangeRate> {
+    // For now, return a mock rate
+    // In production, integrate with price feeds
+    const mockRates: Record<string, number> = {
+      USD: 2500, // sats per dollar (example)
+      EUR: 2700,
+      GBP: 3100,
+    }
+
+    return {
+      currency,
+      satsPerUnit: mockRates[currency] ?? 2500,
+      timestamp: Date.now(),
+      source: 'mock',
+    }
+  }
+
+  /**
+   * Start listening for responses
+   */
+  private startListening(): void {
+    if (!this.nostrClient || !this.identity) return
+    if (this.subscriptionId) return
+
+    this.subscriptionId = this.nostrClient.subscribe(
+      [
+        {
+          kinds: [LIGHTNING_PUB_KINDS.RESPONSE],
+          '#p': [this.identity.publicKey],
+        },
+      ],
+      {
+        onEvent: (event) => this.handleResponse(event),
+      }
+    )
+  }
+
+  /**
+   * Handle incoming response events
+   */
+  private handleResponse(event: Event): void {
+    // Handle async responses if needed
+    // For invoice watching, we use polling instead
+  }
+
+  /**
+   * Send a request to Lightning.Pub
+   */
+  private async sendRequest<T>(request: Request): Promise<T> {
+    if (!this.nostrClient || !this.identity) {
+      throw new Error('Client not initialized')
+    }
+
+    const content = encryptContent(this.identity, this.config.accountPubkey, request)
+
+    const event = finalizeEvent(
+      {
+        kind: LIGHTNING_PUB_KINDS.REQUEST,
+        content,
+        tags: [['p', this.config.accountPubkey]],
+        created_at: Math.floor(Date.now() / 1000),
+        pubkey: this.identity.publicKey,
+      },
+      this.identity.privateKey
+    )
+
+    await this.nostrClient.publish(event)
+
+    // Wait for response
+    return this.waitForResponse<T>(event.id)
+  }
+
+  /**
+   * Wait for a response to a specific request
+   */
+  private waitForResponse<T>(requestId: string): Promise<T> {
+    return new Promise((resolve, reject) => {
+      if (!this.nostrClient || !this.identity) {
+        reject(new Error('Client not initialized'))
+        return
+      }
+
+      const timeout = setTimeout(() => {
+        this.nostrClient!.unsubscribe(subId)
+        reject(new Error('Request timeout'))
+      }, this.config.timeout)
+
+      const subId = this.nostrClient.subscribe(
+        [
+          {
+            kinds: [LIGHTNING_PUB_KINDS.RESPONSE],
+            '#e': [requestId],
+            '#p': [this.identity!.publicKey],
+          },
+        ],
+        {
+          onEvent: (event) => {
+            clearTimeout(timeout)
+            this.nostrClient!.unsubscribe(subId)
+
+            try {
+              const response = decryptJSON<Response<T>>(this.identity!, event.pubkey, event.content)
+
+              if (response.error) {
+                reject(new Error(response.error.message))
+              } else {
+                resolve(response.result as T)
+              }
+            } catch (e) {
+              reject(e)
+            }
+          },
+        }
+      )
+    })
+  }
+
+  /**
+   * Disconnect and clean up
+   */
+  disconnect(): void {
+    if (this.subscriptionId && this.nostrClient) {
+      this.nostrClient.unsubscribe(this.subscriptionId)
+      this.subscriptionId = undefined
+    }
+    this.invoiceCallbacks.clear()
+    this.nostrClient = null
+    this.identity = null
+  }
+}
diff --git a/lamassu-next/packages/lightning/src/index.ts b/lamassu-next/packages/lightning/src/index.ts
new file mode 100644
index 0000000..1535ff8
--- /dev/null
+++ b/lamassu-next/packages/lightning/src/index.ts
@@ -0,0 +1,60 @@
+/**
+ * @lamassu/lightning
+ *
+ * Lightning.Pub client for Nostr-native Lightning operations.
+ *
+ * Lightning.Pub is an account system that wraps LND and provides
+ * CLINK protocol support. This package handles:
+ * - Invoice generation
+ * - Payment processing
+ * - Balance queries
+ * - Exchange rate fetching
+ *
+ * @example
+ * ```typescript
+ * import { LightningPubClient } from '@lamassu/lightning'
+ *
+ * const client = new LightningPubClient({
+ *   serviceUrl: 'https://lightning.pub',
+ *   accountPubkey: 'npub1...',
+ *   relays: ['wss://relay.example.com'],
+ * })
+ *
+ * // Initialize with Nostr client
+ * client.initialize(nostrClient, machineIdentity)
+ *
+ * // Create an invoice
+ * const invoice = await client.createInvoice({
+ *   amountMsat: 100000, // 100 sats
+ *   description: 'ATM withdrawal',
+ * })
+ *
+ * // Watch for payment
+ * client.watchInvoice(invoice.paymentHash, (paid) => {
+ *   console.log('Invoice paid:', paid.preimage)
+ * })
+ *
+ * // Pay an invoice
+ * const result = await client.payInvoice('lnbc...')
+ * if (result.success) {
+ *   console.log('Paid with preimage:', result.preimage)
+ * }
+ * ```
+ */
+
+// Client
+export { LightningPubClient } from './client.js'
+
+// Types
+export type {
+  LightningPubConfig,
+  AccountInfo,
+  Invoice,
+  InvoiceStatus,
+  PaymentResult,
+  ExchangeRate,
+  ChannelInfo,
+  NodeInfo,
+  InvoiceCallback,
+  PaymentCallback,
+} from './types.js'
diff --git a/lamassu-next/packages/lightning/src/types.ts b/lamassu-next/packages/lightning/src/types.ts
new file mode 100644
index 0000000..b7cbed6
--- /dev/null
+++ b/lamassu-next/packages/lightning/src/types.ts
@@ -0,0 +1,113 @@
+/**
+ * Lightning.Pub client type definitions
+ *
+ * Lightning.Pub is a Nostr-native account system that wraps LND
+ * and provides CLINK payment support.
+ */
+
+/** Lightning.Pub account information */
+export interface AccountInfo {
+  /** Account public key */
+  pubkey: string
+  /** Account balance in satoshis */
+  balanceSats: number
+  /** Maximum send amount */
+  maxSendSats: number
+  /** Maximum receive amount */
+  maxReceiveSats: number
+}
+
+/** Invoice status */
+export type InvoiceStatus = 'pending' | 'paid' | 'expired' | 'cancelled'
+
+/** Invoice details */
+export interface Invoice {
+  /** BOLT11 payment request */
+  paymentRequest: string
+  /** Payment hash */
+  paymentHash: string
+  /** Amount in millisatoshis */
+  amountMsat: number
+  /** Invoice description */
+  description?: string
+  /** Creation timestamp */
+  createdAt: number
+  /** Expiry timestamp */
+  expiresAt: number
+  /** Current status */
+  status: InvoiceStatus
+  /** Payment preimage (if paid) */
+  preimage?: string
+}
+
+/** Payment result */
+export interface PaymentResult {
+  /** Whether payment succeeded */
+  success: boolean
+  /** Payment preimage (proof of payment) */
+  preimage?: string
+  /** Fee paid in millisatoshis */
+  feeMsat?: number
+  /** Error message if failed */
+  error?: string
+}
+
+/** Exchange rate information */
+export interface ExchangeRate {
+  /** Fiat currency code */
+  currency: string
+  /** Satoshis per fiat unit */
+  satsPerUnit: number
+  /** Timestamp of rate */
+  timestamp: number
+  /** Source of rate */
+  source: string
+}
+
+/** Lightning.Pub client configuration */
+export interface LightningPubConfig {
+  /** Lightning.Pub service URL */
+  serviceUrl: string
+  /** Account pubkey on Lightning.Pub */
+  accountPubkey: string
+  /** Nostr relays for communication */
+  relays: string[]
+  /** Request timeout in ms */
+  timeout?: number
+}
+
+/** Channel information */
+export interface ChannelInfo {
+  /** Channel ID */
+  channelId: string
+  /** Remote pubkey */
+  remotePubkey: string
+  /** Local balance in sats */
+  localBalanceSats: number
+  /** Remote balance in sats */
+  remoteBalanceSats: number
+  /** Channel capacity in sats */
+  capacitySats: number
+  /** Whether channel is active */
+  active: boolean
+}
+
+/** Node information */
+export interface NodeInfo {
+  /** Node public key */
+  pubkey: string
+  /** Node alias */
+  alias: string
+  /** Number of channels */
+  numChannels: number
+  /** Total capacity in sats */
+  totalCapacitySats: number
+  /** Synced to chain */
+  syncedToChain: boolean
+}
+
+/** Invoice callback for watching payments */
+export type InvoiceCallback = (invoice: Invoice) => void
+
+/** Payment status update callback */
+export type PaymentCallback = (result: PaymentResult) => void
diff --git a/lamassu-next/packages/lightning/tsconfig.json b/lamassu-next/packages/lightning/tsconfig.json
new file mode 100644
index 0000000..d770c39
--- /dev/null
+++ b/lamassu-next/packages/lightning/tsconfig.json
@@ -0,0 +1,22 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true,
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "strict": true,
+    "strictNullChecks": true,
+    "noUncheckedIndexedAccess": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "isolatedModules": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist", "**/*.test.ts"]
+}
diff --git a/lamassu-next/packages/lightning/vitest.config.ts b/lamassu-next/packages/lightning/vitest.config.ts
new file mode 100644
index 0000000..9fb4f14
--- /dev/null
+++ b/lamassu-next/packages/lightning/vitest.config.ts
@@ -0,0 +1,8 @@
+import { defineConfig } from 'vitest/config'
+
+export default defineConfig({
+  test: {
+    include: ['src/**/*.test.ts'],
+    globals: false,
+  },
+})