Node.js vs Firebase Functions: which should you pick?

Node.js and Firebase Functions are not really opposites. Firebase Functions run JavaScript or TypeScript too. The real question is whether you want a traditional backend service or serverless functions tied closely to the Firebase ecosystem.

For small apps already using Firebase Auth, Firestore, and Storage, Firebase Functions can be the fastest path. You can respond to database events, protect API calls, and keep sensitive logic off the client without managing a server.

When I would choose each

I would choose Firebase Functions when the app is Firebase-heavy, the backend logic is event-driven, and the team wants low operational overhead. I would choose a standalone Node.js server when the app needs long-running processes, custom routing, complex integrations, or more control over infrastructure.

The wrong choice is usually not fatal early on. The bigger risk is hiding business logic in random places. Pick the setup that keeps the system easiest to understand and debug.