Free Tools
Decode JWT token safely: 3 ways without online tools
Decode JWT tokens on your own computer with Node.js, PowerShell or a browser tool, read the claims, and see why decoding is not verifying.
· 4 min read
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Latest posts
Error Fixes
EADDRINUSE address already in use: 4 safe fixes
Fix "Error: listen EADDRINUSE: address already in use" in Node.js. Find the process using the port on Windows, stop it, or pick another port.
· 4 min read
How-To
GitHub SSH key on Windows: complete setup in 7 steps
Set up a GitHub SSH key on Windows 11: create an ed25519 key, enable the disabled ssh-agent, add the key to GitHub, and stop Git asking for your passphrase.
· 3 min read
AI Tools
AGENTS.md file: 6 essential sections for AI coding agents
How to write an AGENTS.md file that AI coding agents actually follow: the 6 sections to include, a full example, and how Claude Code, Codex and Cursor read it.
· 4 min read
Interview
Node.js event loop interview questions: 8 tested answers
Node.js event loop interview questions with real, tested output: nextTick vs promises, setTimeout vs setImmediate, async/await, and the ES module twist.
· 4 min read