#Getting started

#Requirements

• Node.js 18 or newer. Node 22+ uses node:crypto; Node 18/20 use the automatic fallback (see Runtime compatibility).
• A Nagad merchant account with: your merchant ID, Nagad's public key, a merchant key pair whose public half you uploaded in the merchant portal, and the API base URL for your environment. Nagad provides these during onboarding. See Key setup.

#Install

npm install nagad-server nagad-client

#Configure

import { createNagad } from 'nagad-server';

export const nagad = createNagad({
  merchantId: process.env.NAGAD_MERCHANT_ID!,
  merchantPrivateKey: process.env.NAGAD_PRIVATE_KEY!, // PEM or base64 body
  pgPublicKey: process.env.NAGAD_PG_PUBLIC_KEY!,
  baseUrl: process.env.NAGAD_BASE_URL!, // from your onboarding details
});

#Create a checkout and verify it

// 1. Create: you decide the amount. Redirect the customer to callBackUrl.
const { callBackUrl, paymentReferenceId, orderId } = await nagad.checkout.create({
  amount: '500.00',
  callbackUrl: 'https://shop.example/api/nagad/callback',
});

// 2. On the callback: verify on the server. Never trust the query string.
const result = await nagad.checkout.verify({
  paymentRefId: req.query.payment_ref_id,
  expectedAmount: '500.00',
});
if (result.success) fulfil(result.orderId);

#The ready-made handler (Express)

import express from 'express';
import { createExpressMiddleware } from 'nagad-server/frameworks';

const app = express();
app.use('/api/nagad', createExpressMiddleware(nagad, {
  basePath: '/api/nagad',
  resolveOrder: async (req) => ({ amount: await cartTotal(req) }),
  allowedCallbackOrigins: ['https://shop.example'],
}));

This serves POST /create and GET|POST /callback. See the server guide.

#Test without Nagad

The repository contains nagad-simulator, a local imitation of the gateway with throwaway keys, used by the SDK's own tests. It is not published to npm yet. See Testing.