Webhook Best Practices

Webhooks are a crucial tool for real-time communication between services. Despite their apparent simplicity, webhooks present complex challenges such as unreliable user endpoints, system reliability, and unique security implications like spoofing, server side request forgery and replay attacks.

Here are some of the best practices we’ve developed through our experience building a secure, reliable, and scalable webhook service for our customers:

📄️Webhook Authentication Best Practices

How to verify webhook requests in practice: HMAC signature checks over the raw body, constant-time comparison, timestamp tolerance, and secret rotation.

📄️Best Practices for Sending Webhooks

Best practices for sending webhooks at scale: architecture for scalability, security layers, retries and reliability, and the UX features consumers expect.

📄️Best Practices for Receiving Webhooks

Best practices for receiving webhooks: verify signatures, block replay attacks with timestamps, handle idempotency, and respond fast with async processing.

📄️Webhook Retry Best Practices

How to retry failed webhook deliveries without causing duplicates or overwhelming a recovering server, covering exponential backoff, jitter, dead letter queues, and a concrete retry schedule.

📄️Webhook Security Best Practices

Sign webhooks with HMAC-SHA256 over payload and timestamp, reject stale signatures, use HTTPS, and block internal IPs to stop SSRF, replay, and spoofing.