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Blog

Long-form posts on regex performance, ReDoS, common-pattern pitfalls, and the JS v flag.

  1. Five regex patterns that will DoS your service via catastrophic backtracking

    Catastrophic backtracking turns an O(n) regex into an O(2^n) regex. Here are the five patterns I've seen take down production, and how to fix them.

    6 min read #regex #performance #redos #security

  2. 30 regex one-liners I actually use weekly (with a tester link for each)

    A field guide to the patterns that come up over and over: emails, URLs, UUIDs, dates, phone numbers, version strings. Each one is annotated, scored on real-world reliability, and paired with a tester deep-link.

    10 min reference #regex #javascript #patterns #cheatsheet