Supabase

Supabase is the most popular open-source Firebase alternative, leveraging PostgreSQL to power over 1 million registered projects and achieve $80M ARR in 2025. Its pgvector extension drives adoption as the top database for embeddings in RAG applications, outperforming #9 competitors with robust real-time subscriptions, Row Level Security, and Edge Functions for AI-native backends. This platform consistently delivers 30% faster query performance for vector searches than the average open-source database solution.