email API with webhooks

If you want an email API with webhooks, the usual pattern is:

1. Send email via API
2. Subscribe to webhook events
3. Receive delivery/bounce/open/click events on your server
4. Use those events to update your app

Common email APIs that support webhooks

• SendGrid — strong webhook/event support
• Mailgun — very common for inbound/outbound events
• Postmark — excellent deliverability and clean webhook events
• Amazon SES — supports notifications via SNS
• Resend — modern API, webhook support
• Brevo (Sendinblue) — email + webhooks

Typical webhook events

• delivered
• opened
• clicked
• bounced
• complained
• dropped
• unsubscribed
• spamreport

Example flow

1) Send an email

POST /send
{
  "to": "user@example.com",
  "subject": "Welcome",
  "html": "<h1>Hello</h1>"
}

2) Register a webhook URL

POST /webhooks
{
  "url": "https://yourapp.com/webhooks/email"
}

3) Handle webhook payload

Your endpoint receives something like:

{
  "event": "delivered",
  "email": "user@example.com",
  "message_id": "abc123",
  "timestamp": 1710000000
}

Important implementation notes

• Verify webhook signatures to prevent spoofing.
• Make your webhook handler idempotent.
• Respond quickly with 200 OK.
• Store event history for auditing/debugging.

If you want to build one yourself

You’d typically need:

• SMTP or provider integration for sending
• Event tracking infrastructure
• Webhook delivery system with retries
• Signature signing and verification
• Admin UI for webhook configuration

If you want, I can also give you:

1. a list of providers compared,
2. a Node.js webhook example, or
3. a full email API design with webhook spec.