Experienced scraping engineers get better results by diagnosing what actually failed, keeping sessions consistent and choosing complexity carefully, not by stacking on more stealth.
Your scraper gets blocked. So you swap the proxies.
Still blocked. You add a stealth plugin, then a new browser, then a CAPTCHA solver.
Each change feels like progress. But each one is a guess, and some of those guesses make things worse. A scraper that rotates its fingerprint every few requests can get blocked faster than one that changes nothing.
The engineers who get consistent results start somewhere else. Before they change anything, they work out what actually failed, and ask one question: does this change address the actual cause?
As freelance anti-bot engineer Ibrahim El Khalil Mlata put it during our recent Reddit AMA:
I treat it like a decision tree, isolate variables one by one, most people jump straight to replacing proxies, but in my experience its often the fingerprint or the scraping behavior
Ibrahim is a web scraping and anti-bot engineer based in Algeria who has spent the last seven years reverse engineering anti-bot defenses across retail pricing, legaltech, logistics, hospitality and AI-training-data pipelines. Among the work he has done: running 1,000+ spiders across 300 retailers, reviving a dead 160-spider fleet, matching 100K+ hotel reviews a month, and taking mobile apps apart with Frida when the website is locked down. You can find his work on GitHub.
In our eleventh r/WebScrapingInsider AMA, we asked Ibrahim how he diagnoses blocks, when reverse engineering is worth the effort, and what keeps a scraping system useful once it is in production.
Here are the nine biggest insights from the discussion.