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Architecture · Beginner

The MVP Architecture

Client-Side vs Full-Stack

Understanding the difference between a 'Browser-Only' prototype and a 'Full-Stack' application. Why your data disappears when you clear cache.

01

The 'Browser as Database' Concept

Many vibe-coded apps (like this one) start as Client-Side MVPs. This means there is no 'Server'. All data lives inside your browser's Local Storage.

  • Pro: Zero cost. No database to configure. Insanely fast.
  • Con: Data is trapped on one device. If you switch from Laptop to Phone, your data is gone.
  • Risk: If you 'Clear Browsing History', you delete your entire database.
FeatureClient-Side (Local)Full-Stack (Cloud)
Data StorageBrowser MemoryPostgres Database
PersistenceFragile (Cache clear wipes it)Permanent
Multi-DeviceImpossibleStandard
Cost$0/mo$5-25/mo

02

The Upgrade Path

You typically start with Client-Side for speed, then upgrade when you have users.

1. MVP

Local Storage

Validate idea. User brings their own API Key.

2. Alpha

BaaS

Add Supabase/Firebase. Users can login and save data.

3. Beta

Backend

Move logic to a real server (Node/Python) for security.

03

Why No Backend Yet?

Adding a backend adds 'Friction'. You have to manage users, passwords, and server bills. Vibe coding prioritizes 'Speed to Reality' first.

“Don't build a server until you have a user.”

— The MVP Philosophy