How do I send receipts and alerts from my backend?

To send receipts and alerts from a backend, you usually do it through a notification/communication service, not directly from your app server.

Common ways

1) Email receipts

Best for purchase confirmations, invoices, account activity.

• Use an email provider like:
  • SendGrid
  • Mailgun
  • AWS SES
  • Postmark
• Your backend sends a request to the provider’s API with:
  • recipient email
  • subject
  • HTML/text body
  • optional template variables

2) Push alerts

Best for mobile or web app alerts.

• Mobile: use Firebase Cloud Messaging (FCM) for Android/iOS
• Web: use Web Push / browser push service
• Your backend sends a push payload to the notification service, which delivers it to the device/browser

3) SMS alerts

Best for urgent short alerts.

• Use Twilio, Vonage, AWS SNS, etc.
• Your backend sends a message to the SMS API

4) In-app notifications

Best for alerts visible inside your product.

• Your backend writes a notification record to your database
• Frontend polls or subscribes via WebSocket/SSE
• The app displays the alert

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Typical backend flow

1. Something happens in your system
   Example: payment succeeds, order ships, password reset requested.

2. Backend creates the message content
   Example: “Your receipt for Order #1234…”

3. Backend sends it through an external service
   Example: email API or push notification API

4. Optionally store a copy in your database
   Useful for audit/history

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Example: sending an email receipt

Backend pseudocode:

await emailService.send({
  to: user.email,
  subject: "Your receipt",
  html: "<h1>Thanks for your purchase</h1><p>Order #1234</p>"
});

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Example: sending a push alert

await fcm.send({
  token: deviceToken,
  notification: {
    title: "Payment received",
    body: "Your receipt is ready"
  }
});

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Recommended setup

If you mean transactional receipts and system alerts:

• Email for receipts
• Push notification for real-time alerts
• Database + in-app notification center for reliability
• Queue jobs for retries if the provider fails

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Important practices

• Don’t send directly from request handlers if it may slow down responses; use a job queue.
• Keep templates separate from business logic.
• Log delivery status and failures.
• Respect user preferences and opt-outs.
• Secure API keys in environment variables.

If you want, I can show you a concrete implementation in Node.js, Python, or PHP for email receipts and alerts.