How I build web scrapers a business can actually rely on

The problem. A business wants to track prices across many online stores — competitors, suppliers, its own catalog. Checking by hand is slow and drifts out of date, and a naive scraper makes it worse: it gets blocked, it breaks the moment a page changes, and it hands back half-parsed HTML nobody can trust. The real question is never "can you scrape it." It is "can I rely on this data tomorrow, and next month."

What I built. A price-intelligence platform that scrapes products across stores, keeps a full price history, detects every change, and shows it on a dashboard and over an API. You can open it right now: https://price-intelligence-demo.onrender.com (free instance, the first request takes about 40 seconds to wake). The code is public, with the test suite and CI badges next to it.

The decisions that make it reliable — the part most scrapers skip:

• Polite by default. It reads robots.txt, holds one request per second per host, and an SSRF guard resolves every URL and refuses private and internal addresses, with no switch to turn that off. This keeps the target site, and you, out of trouble.
• Append-only history. Every product carries its full trend line, its lowest-ever price, and a log of every detected change. Nothing is overwritten, so "when did this move, and by how much" always has an answer.
• One file per store. Adding a new shop is a single new plugin, with no change to the pipeline, the API or the database. The system grows without rewrites.
• Honest data. Tests run against fixtures, offline and deterministic, so the suite proves the parsing is correct instead of depending on a live shop that changes under it.

Proof, not promises. An 80% test-coverage floor is enforced in CI — the build fails if it drops. ruff, mypy and bandit run on every push. And there is a live demo you can click. I do not ask you to take my word for any of it: the badges are live and the code is open.

What this means if you hire me. You get clean, structured data — CSV, JSON, or straight into a database — plus the script and a short guide, so you can run it again yourself. It extends to new sources without a rewrite, and it tells you when something breaks instead of failing silently. Competitor prices, B2B lead lists, or any public dataset: the same discipline applies — sourced, checked, and something you can still trust next month.

Want this for your data? Tell me the site and the fields you need, and I will tell you honestly what is possible. Hire me on Upwork, Freelancer or Fiverr, or email [e-mail].