Supabase

Supabase is an open-source Firebase alternative providing an instant backend with PostgreSQL database, authentication, real-time subscriptions, storage, and edge functions. Unlike Firebase's proprietary NoSQL database, Supabase uses PostgreSQL, giving developers full SQL access, row-level security policies, foreign keys, and joins.

The platform automatically generates RESTful and GraphQL APIs from your database schema using PostgREST, so creating a new table immediately makes it accessible through a typed API. Authentication supports email, OAuth providers, and magic links. Real-time subscriptions push database changes to connected clients via WebSockets. For web developers, Supabase offers a compelling balance between the convenience of managed backend services and the power of a real relational database. Its open-source nature means self-hosting is an option for teams with specific infrastructure requirements.