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Regular Expressions

A regular expression (shortened as regex or regexp also referred to as regular expression) is a sequence of characters that specifies a search pattern.

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25+ useful and commonly used Regular Expressions

25+ useful and commonly used Regular Expressions

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7 min read
The Regex That Took Down Cloudflare for 27 Minutes

The Regex That Took Down Cloudflare for 27 Minutes

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2 min read
Debugging a 41-second regex hang with a regex tester in 2026

Debugging a 41-second regex hang with a regex tester in 2026

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6 min read
Why You Shouldn't Paste Private Logs Into Cloud Regex Testers 🔍

Why You Shouldn't Paste Private Logs Into Cloud Regex Testers 🔍

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2 min read
Stop letting your AI guess: The case for deterministic Regex in MCP

Stop letting your AI guess: The case for deterministic Regex in MCP

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4 min read
Parsing Trading Data With Regex: Test a Whole Suite of Cases at Once, Not One String

Parsing Trading Data With Regex: Test a Whole Suite of Cases at Once, Not One String

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4 min read
The Regex Bug That Passes Code Review, Passes Tests, and Takes Down Prod

The Regex Bug That Passes Code Review, Passes Tests, and Takes Down Prod

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6 min read
Four ways to split sentences (without machine learning)

Four ways to split sentences (without machine learning)

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6 min read
3 Regex Patterns That Save Hours of Debugging

3 Regex Patterns That Save Hours of Debugging

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2 min read
One Bad Regex Can Freeze Node.js: Here's How to Stop It

One Bad Regex Can Freeze Node.js: Here's How to Stop It

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6 min read
How to Clean Messy LLM JSON Output Without Regex Hell

How to Clean Messy LLM JSON Output Without Regex Hell

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2 min read
5 Signs Your Regex Is Wrong (and How to Spot Them in Seconds)

5 Signs Your Regex Is Wrong (and How to Spot Them in Seconds)

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3 min read
A Test-Matrix Workflow for Debugging JavaScript Regular Expressions

A Test-Matrix Workflow for Debugging JavaScript Regular Expressions

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6 min read
TIL: Postgresql's SUBSTRING function

TIL: Postgresql's SUBSTRING function

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1 min read
I Built a Real-Time Regex Tester in the Browser (Capture Groups, Flags, No Libraries)

I Built a Real-Time Regex Tester in the Browser (Capture Groups, Flags, No Libraries)

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2 min read
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