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Practical guides for developers — security, best practices, and technical deep dives.

Reference

How to Generate a UUID in JavaScript, Python, Go, Rust and More

Copy-paste UUID generation code for every major language: JavaScript, TypeScript, Node.js, Python, Go, Rust, PHP, Java, C# and the command line.

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CSS

HEX vs RGB vs HSL: Which Color Format Should You Use in CSS?

HEX, RGB, and HSL all describe the same colors — but each has a different use case in CSS. Learn when to use each and how to convert between them.

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Security

Why You Should Never Paste JWT Tokens Into Online Tools

Most online JWT decoders send your token to a server. A JWT payload contains user data, roles, and session info — here's what the risk actually is.

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Security

The Hidden Risk of Server-Side Developer Tools

Most online dev tools look identical whether they're client-side or server-side. Here's how to tell the difference and why it matters for your data.

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Utilities

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