Crypto payment API built for stablecoin checkout

import crypto from 'node:crypto'
import express from 'express'

const app = express()
app.use(express.json())

app.post('/api/checkout', async (req, res) => {
  const payload = JSON.stringify({
    externalOrderId: req.body.orderId,
    amount: req.body.amount,
    currency: 'USDT',
    network: 'TRC20',
    notifyUrl: 'https://merchant.com/webhooks/boltutil',
    returnUrl: 'https://merchant.com/orders/complete'
  })
  const timestamp = Date.now().toString()
  const signature = crypto
    .createHmac('sha256', process.env.BOLTUTIL_API_SECRET)
    .update(`${timestamp}.${payload}`)
    .digest('hex')

  const response = await fetch('https://api.boltutil.com/api/v1/order/create', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'X-Bolt-Key': process.env.BOLTUTIL_API_KEY,
      'X-Bolt-Timestamp': timestamp,
      'X-Bolt-Signature': signature
    },
    body: payload
  })

  res.status(response.status).json(await response.json())
})