Firebase vs Supabase: A Detailed Comparison Guide for Developers

Introduction

Picking up frontend frameworks for my projects has always been a fairly easy thing for me to do. After all, migrating from one to another is usually not that difficult. However, I can't say the same for backend solutions. With backend solutions, there are a million and one things you need to consider. Things like database structures, performance, underlying technology, security, integration with other developer tools and services, and so much more. In your search for a backend solution, 9/10 times your search will narrow down to two main options: Firebase and Supabase. In this blogpost, I will share with you differences between Firebase and Supabase, two popular backend-as-a-service platforms, and make a case for why you might choose one over the other.

The case for backend-as-a-service (BaaS)

Why use a backend-as-a-service (BaaS) anyway? Isn't a database instance all you need? Well, not exactly. A database instance is just a place to store your data. But as your application becomes more complex, you will need more than just a database. You will need a way to manage your users, handle authentication, realtime capabilities, vector databases especially if you are building AI applications, and perform server-side logic. BaaS platforms were built to solve this exact problem. They provide a complete suite of backend tools or services, allowing you to focus on the most important thing: ship your application.

What are the benefits of using a BaaS?

• Speed: BaaS platforms provide ready-to-deploy backend services that can be easily plugged in into your apps, without the need to build everything from scratch.

• Scalability: If your application grows, and you need to handle more users or data, BaaS platforms can scale with you.

• Cost-effectiveness: Most BaaS platforms have three or more services morphed into one product that you pay based on usage.

• Security: BaaS platforms have built-in security features, such as authentication, Row-level security, to help protect your application and most importantly your data.

Firebase Overview

Firebase emerged in the 2010s, acquired by Google later, and incorporated into the Google Cloud Platform ecosystem. Firebase has been the go to BAAS especially for mobile applications. The Firebase suite of products include:

• Firestore - NoSQL document database with realtime synchronization
• Realtime Database - JSON-based NoSQL database built for realtime operations
• Authentication - Complete user management operations with multiple providers (Google, Github, X, etc.)
• Cloud Functions - Serverless compute platform for backend logic
• Cloud Storage - Object storage for media and files
• Analytics - App usage and user engagement insights(very useful for mobile applications)

Supabase Overview

Supabase, describes itself as an open-source Firebase alternative, and in many ways it is. Most of the features you find in Firebase, you will find in Supabase. However, Supabase is built on top of PostgreSQL, I will do a deep dive into the Supabase architecture in a future article. The Supabase suite of products include:

• Supabase PostgreSQL - PostgreSQL database with ACID compliance
• Authentication - Row-level security with JWT-based authentication
• Edge Functions - Serverless TypeScript functions deployed globally
• Storage - S3 Object storage with automatic image transformations
• Realtime - Database changes streamed via WebSockets
• Auto-generated APIs - RESTful and GraphQL APIs generated from your database schema
• Dashboard - Built-in database management and query tools

Key Differences Between Firebase and Supabase

The following are some of the key differences between Firebase and Supabase:

1. Database Technology

The most important difference between Firebase and Supabase is the database type they use. Firebase has two database product offerings: Firestore and Realtime Database, which are both NoSQL databases. On the other hand, Supabase uses Supabase PostgreSQL, which is an unmodified fork of PostgreSQL, a powerful and widely-used relational database.

2. Open Source vs Proprietary

Supabase is built entirely on open-source software. The codebase, including the database (PostgreSQL), authentication system, and API layer, is available on GitHub. This means you can self-host Supabase, on your own infrastructure if needed, reducing vendor lock-in.

If you pick to self-host Supabase, have a look at Coolify, an open-source PaaS that makes it easy to deploy and manage Supabase on your own servers. Coolify GitHub Repository

Firebase is a proprietary Google service built on closed-source technology. While it integrates seamlessly with Google Cloud Platform, you cannot self-host Firebase or access its underlying technologies.

3. Query Capabilities and Performance Patterns

Firestore uses NoSQL query patterns with limited joining capabilities. Complex queries requiring data from multiple collections need client-side processing or denormalization. Queries are optimized for simple reads and writes but struggle with complex analytical operations.

// example Firestore query
const userPosts = await db.collection('posts')
  .where('userId', '==', userId)
  .orderBy('createdAt', 'desc')
  .limit(10)
  .get();

Joining with user data requires separate query.

With Supabase, performing SQL queries is much easier and more powerful. You can perform including complex JOINs, subqueries, window functions, and more. The auto-generated REST API supports these operations too.

// query with joins example
const { data } = await supabase
  .from('chats')
  .select(`
    *,
    users(name, avatar),
    comments(count)
  `)
  .eq('status', 'published')
  .order('created_at', { ascending: false });

4. Authentication and Security Models

Firebase Authentication provides a managed identity management system with built-in providers (Google, Facebook, Github, etc.) and custom token generation. Security is enforced through Firestore Security Rules, which use a proprietary rule language for document-level access control in Firebase.

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /posts/{postId} {
      allow read: if resource.data.published == true;
      allow write: if request.auth != null && request.auth.uid == resource.data.userId;
    }
  }
}

Supabase Authentication implements Row Level Security (RLS) policies in PostgreSQL, utilizing JSON Web Tokens (JWTs) to enable granular, SQL-based security rules that reference complex database relationships.

-- Supabase RLS Policy example
CREATE POLICY "Users can only access their own chats" ON chats
  FOR SELECT USING (auth.uid() = user_id);

CREATE POLICY "Users can update their own chats" ON chats
  FOR UPDATE USING (auth.uid() = user_id);

5. Real-time Implementation and Scalability

Real-time synchronization between Firebase Realtime Database and Firestore is accomplished through proprietary WebSocket connections, which also offer automated conflict resolution and offline functionality. These systems are built to sustain millions of connections at once with constant latency.

Supabase Realtime streams database changes via WebSocket connections by utilizing PostgreSQL logical replication. It enables real-time functionality at the database level by converting PostgreSQL Write-Ahead Log (WAL) entries into events.

// example
const subscription = supabase
  .channel('chats')
  .on('postgres_changes', 
    { event: 'INSERT', schema: 'public', table: 'chats' },
    (payload) => console.log('New chat:', payload.new)
  )
  .subscribe();

Summary Table

Feature	Firebase	Supabase
Database	NoSQL (Firestore, Realtime DB)	SQL (PostgreSQL)
Open Source	No	Yes
Authentication	Built-in	Built-in
Realtime Capabilities	Yes	Yes
Serverless Functions	Yes (Cloud Functions)	Yes (Edge Functions)
Storage	Yes	Yes
Pricing Model	Pay-as-you-go	Pay-as-you-go
Vendor Lock-in	High	Low
Community and Ecosystem	Large and mature	Growing and active
Vector Database Support	Yes	Yes

Note: Other BAAS platforms worth mentioning include Appwrite, Nhost, and Pocketbase.

Conclusion

Firebase and Supabase are both very capable and mature BAAS products. On what to choose, it all depends on what you are building, how you are building it, compliance requirements and budget. Firebase has been around for longer, if that is what your are familiar with, it's probably better to stick with it. However, if SQL is your strongest suit, and you value open-source software, Supabase would be a better fit.