How We Built a Rate Limiter for Outbound Webhooks

The text describes the development of a rate limiter for outbound webhooks by Hookdeck. The goal was to create a reliable and adjustable queueing system that would allow users to process webhooks asynchronously at a predetermined rate without tampering with their inherent simplicity. To achieve this, they built a configurable "Push" queue per user's individual use case and infrastructure capacity. The architecture includes Rate Limiter Jobs, Delivery Queues and Workers, Short Circuiting, Shutdown and Restart Per Destination, Redundancy and Scaling, Testing and Auditing. They also introduced an essential metric on the attempt called delivery_latency to ensure stability and proper adherence to rate limits. Future enhancements include Smart Delivery and Backlog Alerts.