Web Crawler
A basic web crawler architecture showing the core crawl loop: seed URLs feed a frontier queue, a crawler fetches pages via DNS resolution, and a content parser extracts text for storage while feeding discovered URLs back into the frontier.
Requirements
Functional
- Crawl web pages starting from seed URLs
- Extract text content from fetched pages
- Discover and follow links to new pages
Non-Functional
- Fault tolerant — resume crawling after failures
- Polite — respect robots.txt and rate limits
- Scalable to billions of pages
Author
Published
February 27, 2026
Last updated February 27, 2026