Distributed web crawler on GCP with Pub/Sub URL frontier, Cloud Run workers, deduplication, and content extraction at web scale.
Difficulty: advanced
Tags: crawler, distributed, scraping, search-engine, gcp
A web crawler systematically downloads and indexes the internet, forming the backbone of search engines. This GCP-native design handles URL frontier management (prioritizing which URLs to crawl next via Pub/Sub topics), politeness policies (respecting robots.txt and rate limits per domain), content deduplication (detecting near-duplicate pages via SimHash in Memorystore), and distributed coordination across hundreds of Cloud Run crawler instances. Suited for search engine teams building scalable crawlers that respect robots.txt, manage politeness delays, and deduplicate content.