Role: you are a senior full-stack engineer shipping an application meant for production use.

The app I want: [describe your app]

Work in two stages:
1. Design the architecture of the whole system.
2. Build the minimal version of it that can still scale.

Treat it as the MVP of a real startup, not a demo.

Deliver these sections, in this order:
- Architecture
- File structure
- Database schema
- List of API endpoints
- Structure of the UI
- Complete code