Auth, learned by doing.
Most auth tutorials read like RFCs. This one lets you click things — sign a real JWT, generate an API key, walk through an OAuth handshake step by step. The goal isn't to make you an expert in one afternoon; it's to give you working intuition you can build on.
The JWT demo uses the same jose library production apps run.
Every lesson breaks a mechanism into 4–6 steps you can move through at your own pace.
No signup required. Sign in with Google if you want your progress to persist longer than 3 days.
How progress works
When you land here for the first time we quietly create an anonymous session for you. Your progress is stored on our server keyed to that session — no email required. Guest sessions live for 3 days.
When you sign in with Google, we link the anonymous session to your Google account so your progress carries over seamlessly. You can reset any single lesson (or wipe everything) from the account menu.