Best Practices

Building a Firebase app is easy, but building a scalable, secure, and cost-effective app requires following these industry best practices.

1. Security First

• Rules: Never ship an app with `allow read, write: if true`.
• App Check: Enable App Check to prevent unauthorized API use.
• Secrets: Never store private keys in your frontend code.

2. Database Design (Firestore)

• Avoid Deep Nesting: Flat structures are generally easier to query.
• Sub-collections vs. Documents: Store large amounts of data in sub-collections, not large arrays within a document.
• Denormalize: Duplicating a bit of data is often better than making multiple queries (since Firestore is billed per read).

3. Cost Optimization

• Be Mindful of Reads: Avoid fetching entire collections if you only need a few documents.
• Limit Query Results: Always use limit() when possible.
• Monitor Billing: Set up budget alerts in the Google Cloud Console.

4. Offline-First Approach

Always assume the user has a poor connection. Enable persistence and show loading states/cached data where appropriate.