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Kestrel Tools CSV/JSON converter showing a CSV cell starting with an = sign flagged as a formula-injection risk

engineering

Why That Innocent CSV Export Can Pop a Calculator (CSV Injection, Explained)

CSV formula injection turns a harmless export into a remote-execution risk in Excel and Sheets. Here's how it works and how to prevent CSV injection in 2026.

Kestrel Tools Regex Tester showing a backtracking step counter spiking on the input aaaaaaaaaaaaaaaaa! against the pattern (a+)+$

developer-tools

Catastrophic Backtracking Killed Cloudflare Once. What Should Your Regex Tester Be Showing You?

Regex catastrophic backtracking in JavaScript: how to spot a vulnerable pattern, why (a+)+ pegs a CPU, and what your regex tester should show.

Kestrel Tools Color Converter showing the same blue rendered in OKLCH, HSL, and HEX side by side with a perceptual gradient strip below

developer-tools

OKLCH vs HEX vs HSL: Which CSS Color Format Should You Actually Write in 2026?

OKLCH vs HEX vs HSL in 2026: OKLCH for new design tokens, HSL for quick tweaks, HEX as the export format. Here's how to pick.

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