From 0 to 20 billion - How We Built Crawler Hints

What this post added

This post details the engineering behind Cloudflare's Crawler Hints product. It explains how cache misses from Cloudflare's global CDN network are captured, processed, and used to generate a content freshness score. The system utilizes Kafka for buffering cache miss data, Redis as a distributed buffer for aggregation and deduplication, and a dispatcher service to send batches of URLs to search engine partners via the IndexNow API. The post highlights the challenges of scaling such a system, including handling high traffic volumes, ensuring data deduplication and batching, and implementing customer opt-in mechanisms for rollout.