You can use firebase to skip backend programming, or even user firebase to setup a nodejs backend (functions) . The bad thing about not using a backend is security, you would need to master firebase security rules to completely protect data.
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Frontend Developers can use Firebase to store and retrieve data to and from a NoSQL database called Firestore, as well as to authenticate their app’s users with the Firebase Auth service . While Firestore, the Realtime Database is really just one big JSON object that the developers can manage in realtime.
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