🔐 I Finally Understood JWT Auth - After Building Refresh Token Rotation From Scratch

JWT tutorials only teach the easy part. Here's what happens after. Most auth tutorials end at "user logs in, gets a token, done." And for a while, that felt fine to me too. Then the uncomfortable questions showed up. What if the refresh token is stolen? How do you actually revoke a session? How do you know which device is logged in? That's the point where I realized I needed to build something real to understand auth properly. So I built refresh token rotation backed by server-side session tracking - and it changed the way I think about authentication entirely. 😅 The Problem With "Basic" JWT Auth A lot of beginner tutorials go like this: ✅ Create a token when the user logs in ✅ Send it to the client ✅ Verify it on protected routes That works. Until it doesn't. Fully stateless JWT auth makes some critical things hard: ❌ You can't easily revoke sessions ❌ You can't safely manage multiple devices ❌ A stolen refresh token stays valid until it expires (which could be days or weeks) ❌ "Logo