Vibe Coding · Lesson

Storing Data Simply

From local storage to a real database.

Storing Data Simply is a free Vibe Coding lesson on CoddyKit — lesson 3 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Vibe Coding learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.

Data That Sticks Around

Most apps need to remember things: your to-do list, your saved notes, the dark-mode setting you chose. Without storage, everything disappears when you refresh the page.

The good news: you can go from 'remembers nothing' to 'remembers everything' just by describing what to save — AI handles the storage code.

The Storage Ladder

There are levels of storage, from simplest to most powerful. Start low and climb only when you need to:

In memory — fast but forgotten on refresh
Local storage — saved in the user's browser, survives refresh
A database — shared across devices and users, the real deal

Telling AI which rung you want keeps your app as simple as possible.

Saving to the Browser

The easiest persistent storage is localStorage — a little notebook the browser keeps for your app. It's perfect for settings and small lists on a single device.

You don't need a server or account for this. A prompt like the one below adds it instantly.

Make my to-do list save to the browser's
localStorage so my tasks are still there after I
refresh the page. Load them automatically when the
page opens.

How localStorage Works

localStorage stores text by a name (a 'key'). To save objects or lists, you turn them into JSON text first, then turn them back when reading.

Run this to see the pattern AI uses: save a value, then read it back.

const settings = { theme: 'dark', fontSize: 16 };

const saved = JSON.stringify(settings);
console.log('Saved text:', saved);

const loaded = JSON.parse(saved);
console.log('Theme is:', loaded.theme);

When localStorage Isn't Enough

localStorage only lives in one browser on one device. If you want users to see their data on their phone and laptop, or share data between users, you need a database on a server.

That sounds scary, but tools make it easy. You'll describe what to store, and AI sets up the database calls.

Easy Databases for Vibe Coders

You don't need to run your own server. Hosted databases give you storage with almost no setup:

Supabase — a friendly database with built-in login, great with AI tools
Firebase — Google's real-time database
Airtable — a spreadsheet that acts like a database

Builders like Bolt, Lovable and Replit can connect these for you when you ask.

Adding a Database by Prompt

To add real storage, describe what you're saving and where. Naming Supabase (a popular choice) tells AI exactly which setup to generate.

This prompt turns a local-only app into one with a shared, persistent database.

Connect this app to Supabase. Create a table called
notes with columns: id, title, content, and
created_at. Update the app so saving a note inserts
a row, and the homepage loads all notes from the
table, newest first.

Thinking in Tables

A database stores data in tables — like spreadsheets with named columns. A 'notes' table might have a title, content, and a date. Each saved note is one row.

You don't need to master database design. Just tell AI what fields each thing has, and it builds the table for you.

Create, Read, Update, Delete

Almost every data app does four things, nicknamed CRUD: Create new items, Read them back, Update them, and Delete them. If your app can do all four, it's a real tool.

You can ask AI to add them one at a time, testing each before moving on.

Add full editing to my notes app: I should be able
to create a note, edit an existing note's title and
content, and delete a note with a confirm dialog.
Keep everything saved to Supabase.

Start Simple, Upgrade Later

The pro move is to start at the lowest rung that works. Building a quick prototype? localStorage. Need it on every device? Move up to a database. AI can even migrate you — 'switch my app from localStorage to Supabase.'

Don't over-engineer early. Match the storage to what your app actually needs today.

My app currently uses localStorage. Migrate it to
use Supabase instead so my data syncs across
devices, and move any existing local data into the
database on first load.

Backups and Not Losing Data

Data is precious — users get upset if it vanishes. Hosted databases like Supabase and Firebase keep backups for you, which is another reason to graduate from localStorage for anything important.

You can also let users export their own data as a safety net. Ask AI to add a one-click backup so nobody loses their work.

Add a "Download backup" button that exports all my
notes from the database as a JSON file, and an
"Import backup" option that restores them. This
way users never lose their data.

Quick Check

You built a notes app that uses the browser's localStorage. A user complains they can't see their notes when they open the app on their phone. What kind of storage do they actually need?

Recap: Storing Data Simply

You learned the storage ladder: in-memory, then localStorage for single-device persistence, then a real database for cross-device, shared data.

You saw how to save settings in the browser, when to upgrade to hosted databases like Supabase, how data lives in tables, and the CRUD actions every data app needs. Start simple and let AI upgrade you. Next: keeping your API keys and secrets safe.

Frequently asked questions

Is the “Storing Data Simply” lesson free?

Yes — the full text of “Storing Data Simply” is free to read here on the web, and the Vibe Coding course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Vibe Coding course, upgrade to CoddyKit PRO.

What will I learn in “Storing Data Simply”?

From local storage to a real database. You practise Vibe Coding with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start Vibe Coding?

No prior experience is required. Vibe Coding on CoddyKit is structured for beginners through advanced learners; this is — lesson 3 of 4, so you can start here or from the beginning and move at your own pace.

How long does the “Storing Data Simply” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this Vibe Coding lesson?

Yes. Every Vibe Coding lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

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