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Lesson 4 of 7

Connect a backend & data

7 min read

You add a task to your shiny new app, refresh the page — and it's gone. Where did your data go, and how do you make it stay?

Without a backend, nothing sticks

The app you see is the front — the screen. To remember anything, it needs a [backend](glossary://backend): a place on a server to store data. Without one, everything lives only in the open page, so a refresh wipes it. Ask your tool to "add a database" and it wires one up — now your data is saved and comes back every time.

A backend is where your app's data lives between visits. No backend means no memory: refresh, and it starts blank.

Accounts make it personal

Add sign-in and the app knows who each visitor is, so it can keep everyone's data separate and private — your tasks are yours, not shared with every stranger. "Add user accounts" is another thing you can simply ask for; the tool sets up the login and the per-person storage behind it.

Accounts let one app serve many people, each with their own private, saved data — the difference between a demo and something usable.

Once real people's data is involved, so is real responsibility — passwords, private details, privacy rules. It's fine to vibecode the setup, but treat anything holding personal data with extra care.

The shape of it

Your note-taking app forgets everything the moment you refresh. What does it need?

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