Step 2 of 6
Separation of concerns and layers
Keep the UI, the business rules and the data access in separate places. A typical split: components (what it looks like), services or server functions (what it does), and a data layer (how it's stored).
Why it matters when you build with AI: When the AI puts a database query, pricing logic and HTML into one component, every future change risks breaking all three.
Quick check
A component that queries the DB, computes prices and renders HTML is…
Split UI, business logic and data access so changes don't ripple.