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

A reliable webhook system is now a baseline expectation for API providers.

📄️ Best Practices for Receiving Webhooks

At Svix we often focus on sending webhooks, but receiving them well matters just as much.

📄️ 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.