Joe Rutkowski — Notes

Long-form write-ups on browser fingerprinting, bot detection, reverse engineering, and the parts of web security that only show up when you read the bytes.

• August 14, 2026·2 min read

  Feature Detection for Headless and Automated Browsers

  A tour of the common JavaScript surface that differs between a driven browser and a human-driven one, and why every check is a heuristic.

  bot-detectionautomationjavascript
• August 10, 2026·2 min read

  Canvas Fingerprinting, End to End

  A walkthrough of how a canvas fingerprint is produced in the browser, and how to hash the result with the Web Crypto API.

  fingerprintingjavascriptweb-crypto