Supabase vs PlanetScale

Supabase is an open-source backend-as-a-service platform that provides developers with a full suite of tools for building modern applications — all built on top of PostgreSQL, the world's most advanced open-source relational database. Founded in 2020 by Paul Copplestone and Ant Wilson, Supabase positions itself as the open-source alternative to Firebase, offering a relational database, authentication, real-time subscriptions, file storage, edge functions, and vector embeddings — with the crucial difference that your data lives in a standard PostgreSQL database you can always take with you. In just four years, Supabase has grown to over 1 million databases created and has raised over $116 million in funding, attracting developers frustrated by Firebase's proprietary lock-in and NoSQL limitations.

PostgreSQL at the Core

Unlike Firebase's Firestore (a proprietary NoSQL document database), Supabase gives you a full PostgreSQL database with no restrictions. This means you get ACID transactions, complex joins, foreign keys, views, stored procedures, triggers, and the entire ecosystem of PostgreSQL extensions. You can use PostGIS for geospatial queries, pg_trgm for fuzzy text search, pgcrypto for encryption, and hundreds of other extensions. The Supabase Dashboard includes a Table Editor (a spreadsheet-like interface for viewing and editing data), a SQL Editor for running raw queries, and database management tools for managing roles, policies, and extensions. Crucially, because it is standard PostgreSQL, you can connect any PostgreSQL-compatible tool — pgAdmin, DBeaver, Prisma, Drizzle, or your application's ORM — directly to your database.

Row Level Security (RLS)

Row Level Security is a PostgreSQL feature that Supabase makes central to its security model. RLS lets you define fine-grained access policies directly in the database — for example, 'users can only read their own rows' or 'admins can update any row in the orders table.' These policies are written as SQL expressions and enforced at the database level, meaning they apply regardless of how the data is accessed (API, direct connection, edge function). This is a fundamentally different security model from Firebase's security rules — it is more powerful because it uses full SQL, and more robust because it cannot be bypassed by client-side code. However, writing effective RLS policies requires solid SQL knowledge and careful testing.

Realtime Subscriptions

Supabase Realtime lets your application listen for changes in the database and receive updates instantly via WebSocket connections. You can subscribe to INSERT, UPDATE, and DELETE events on specific tables, filtered by columns or RLS policies. This enables live features like chat messages, collaborative editing, live dashboards, and real-time notifications without polling. Supabase Realtime also supports Presence (tracking which users are online) and Broadcast (sending arbitrary messages between clients) — features useful for building collaborative applications. The system scales to thousands of concurrent connections on paid plans.

Authentication and User Management

Supabase Auth (built on GoTrue) provides a complete authentication system supporting email/password, magic links, phone/SMS OTP, and over 20 OAuth providers including Google, GitHub, Apple, Discord, and Twitter. It handles email verification, password recovery, session management, and JWT token issuance. Auth integrates directly with RLS — the authenticated user's ID is available in RLS policies via auth.uid(), creating a seamless connection between who is logged in and what data they can access. Multi-factor authentication (TOTP) is supported, and enterprise features like SAML SSO are available on higher-tier plans.

Storage, Edge Functions, and pgvector

Supabase Storage provides S3-compatible file storage with the same RLS-based access control as the database. You can create storage buckets, upload files, generate signed URLs, and transform images (resize, crop, format conversion) on the fly. Edge Functions are server-side TypeScript functions that run on Deno Deploy, allowing you to execute custom backend logic — webhooks, third-party API calls, complex business logic — without managing servers. They deploy globally to edge locations for low latency. Finally, Supabase's integration with pgvector brings AI capabilities to your database: you can store and query vector embeddings directly in PostgreSQL, enabling semantic search, recommendation systems, and RAG (Retrieval-Augmented Generation) pipelines without a separate vector database like Pinecone or Weaviate.

Open Source and Portability

Supabase is fully open source under the Apache 2.0 license. You can self-host the entire stack using Docker — database, API gateway (PostgREST), Auth, Realtime, Storage, and Dashboard — on your own infrastructure. This eliminates vendor lock-in: if Supabase's hosted service shuts down or changes pricing, you can migrate to self-hosted or any PostgreSQL provider. This portability is Supabase's philosophical foundation and its strongest argument against proprietary alternatives like Firebase.