AI Web Crawler: Build a Search-Engine-Grade Crawler with Open Source
An AI web crawler uses LLMs for extraction and prioritization. We compare Crawlee, Scrapy, browserless and the modern crawling architecture.
💡 What You Will Learn
An AI web crawler uses LLMs for extraction and prioritization. We compare Crawlee, Scrapy, browserless and the modern crawling architecture.
Crawling is easy until you need to do it politely, at scale, without getting banned. An AI web crawler adds the modern twist: LLM-based content extraction and smart prioritization on top of the classic crawl-parse-store loop.
The Modern Stack
Crawlee (apify/crawlee, 25,204 stars) is the core: handles queues, robots.txt, retries, and headless browsers, with built-in LLM extraction now. Browserless (browserless/browserless, 13,557 stars) provides managed headless browsers as a service you can self-host - handles the anti-bot arms race for you. Scrapy (63,669 stars) remains the engine for massive, well-structured crawls.
Architecture: Crawlee (or Scrapy) manages the crawl frontier, browserless renders JavaScript pages, an LLM extracts structured fields, and the results feed a search index (Meilisearch, 58,868 stars, or Typesense, 26,402 stars). Respect robots.txt and rate limits - polite crawlers get better data and fewer blocks.
Comparison
| Tool | Role | Stars |
|---|---|---|
| Crawlee | Crawl frontier | 25,204 |
| Browserless | Headless rendering | 13,557 |
| Scrapy | Mass crawl engine | 63,669 |
| Meilisearch | Search index | 58,868 |
FAQ
Q: How do I avoid getting blocked?
A: Respect robots.txt, throttle requests (1-3s), rotate User-Agents, and render JavaScript only when needed - browserless helps with fingerprint management.
Q: How fast can I crawl?
A: Politely: hundreds to a few thousand pages/hour on a single machine, limited by rate limits rather than hardware.
