Exploring Supabase - the PostgreSQL-powered backend-as-a-service that's revolutionizing full-stack development.
Supabase is an open-source alternative to Firebase, built on PostgreSQL instead of proprietary NoSQL. It gives you a real SQL database, authentication, file storage, real-time subscriptions, and serverless functions. Being PostgreSQL underneath means you're not locked in. You can dump your data and move it anywhere.
Firebase has problems. The NoSQL data model is limiting for relational data. Pricing scales unpredictably. You're locked into Google's ecosystem. The Firestore query model is awkward compared to SQL. Supabase solves these by using standard PostgreSQL with smart tooling. You get full SQL with all of PostgreSQL's features plus real-time subscriptions and auth.
The database is just PostgreSQL. You can use joins, foreign keys, transactions, triggers, and stored procedures. The web dashboard generates TypeScript types from your schema. Row Level Security policies control data access at the database level, so users can only see and modify their data. This is more secure than application-level authorization because it's enforced even if your code has bugs.
Authentication is full-featured. Email/password works out of the box. OAuth providers like Google, GitHub, and Twitter are configured in the dashboard. Magic link authentication sends a login link. JWT tokens are handled automatically. User sessions integrate with RLS policies, so queries filter based on who's logged in.
Real-time subscriptions use PostgreSQL's LISTEN/NOTIFY. You can subscribe to changes on any table. When a row is inserted, updated, or deleted, subscribers get notified over WebSockets. This makes building collaborative apps straightforward. You can use broadcast channels for presence tracking.
Edge Functions run on Deno at the edge. They're useful for webhooks, scheduled jobs, or API integrations. The Deno runtime is more secure than Node.js and supports TypeScript natively. You deploy functions with the Supabase CLI.
File storage is S3-compatible. You can upload images, videos, or any files. The storage integrates with RLS policies to control uploads and downloads. Image transformations can resize or crop on the fly. The CDN caches files globally.
The development experience is good. The JavaScript client handles auth state automatically. TypeScript types are generated from your schema, giving you autocomplete for tables and columns. Migrations are SQL files you can version control. Local development runs a full stack in Docker.
The free tier is generous. You get 500MB database space, 1GB file storage, and 2GB bandwidth monthly. Paid plans start at $25/month. This is cheaper than Firebase. Pricing is predictable, based on database size and bandwidth.
Self-hosting is an option since everything is open-source. You can run Supabase on your infrastructure for full control. The Docker setup is documented, though managed hosting is easier.
Limitations exist. Connection pooling matters because PostgreSQL uses one process per connection. The free tier has low connection limits. Database size is limited on lower tiers. Real-time can get expensive with thousands of concurrent users. RLS policies can get complex.
Supabase vs custom backend is a tradeoff. Supabase gets you going fast. Custom backends give more control. For MVPs and many production apps, Supabase wins. For complex applications, you might outgrow it.
The PostgreSQL foundation makes Supabase credible. You're using proven technology. If Supabase shuts down, your data is portable.