Firebase vs. Supabase, A Technical Comparison

In recent years, backend-as-a-service (BaaS) platforms have become increasingly popular, providing developers with powerful tools to accelerate application development. Firebase and Supabase are two such platforms, both offering a rich set of features. However, choosing between them can be challenging. 

This article provides a technical comparison of Firebase and Supabase, focusing on their core offerings, strengths, and weaknesses, helping developers decide which platform to use and when.

Overview of Firebase and Supabase

Firebase is a BaaS platform developed by Google, offering a suite of cloud services to help developers build and scale applications. It provides real-time databases, authentication, cloud functions, analytics, and hosting, among other features. Firebase's key selling point is its seamless integration with other Google Cloud services, making it an excellent choice for developers already within the Google ecosystem.

Supabase, on the other hand, is an open-source alternative to Firebase, built on top of PostgreSQL. It aims to provide similar features to Firebase, such as real-time databases, authentication, and storage, while offering the flexibility and transparency of an open-source solution. Supabase is designed to be SQL-first, making it a natural fit for developers comfortable with SQL.

Core Features Comparison

Database: NoSQL vs. SQL

• Firebase: Firebase's database offerings include Firestore (a NoSQL document store) and the Realtime Database (also NoSQL). Firestore is designed for scalability and performance, with strong consistency. At the same time, the real-time database is optimized for low-latency updates, making it suitable for real-time applications like chat apps or live collaboration tools.
• Supabase: Supabase uses PostgreSQL as its core database, providing a relational model with strong support for SQL. PostgreSQL’s robustness and feature set make Supabase an attractive option for applications requiring complex queries, transactions, and relational data. Supabase also offers real-time updates using PostgreSQL's LISTEN/NOTIFY mechanism.

Example: Querying Data

• Firebase Firestore (NoSQL):

const db = firebase.firestore();
const snapshot = await db.collection('users').where('age', '>', 18).get();
snapshot.forEach(doc => {
  console.log(doc.id, '=>', doc.data());

• Supabase PostgreSQL (SQL):

const { data, error } = await supabase
  .from('users')
  .select('*')
  .gt('age', 18);
console.log(data);

When to Choose:

• Choose Firebase if you need a NoSQL database that scales easily with minimal configuration, especially for real-time data synchronization across clients.
• Choose Supabase if you prefer SQL and require a relational database with robust query capabilities and ACID compliance.

Authentication

Both Firebase and Supabase offer authentication services with support for various providers such as Google, Facebook, GitHub, and email/password login.

• Firebase: Firebase Authentication is highly integrated with other Firebase services, making it easy to manage user sessions and roles. It also supports multi-factor authentication and integrates seamlessly with Firebase's security rules.
• Supabase: Supabase Authentication is built on top of GoTrue, the same library used by Netlify Identity. It supports similar authentication providers and offers email confirmations, magic links, and user management out of the box. Supabase’s advantage is the ability to leverage SQL for custom access controls and policies.

Example: User Authentication

• Firebase Authentication:

firebase.auth().signInWithEmailAndPassword(email, password)
  .then((userCredential) => {
    // Signed in
    var user = userCredential.user;
  })
  .catch((error) => {
    console.error(error);
  });

• Supabase Authentication:

const { user, error } = await supabase.auth.signInWithPassword({
  email: 'user@example.com',
  password: 'example-password',
});
console.log(user);

When to Choose:

• Choose Firebase if you need a battle-tested authentication system with deep integration into a broader ecosystem.
• Choose Supabase if you prefer an open-source alternative with a SQL-first approach to user management and custom access controls.

Functions: Serverless Computing

• Firebase: Firebase Cloud Functions allow you to run server-side code in response to events triggered by Firebase features or HTTPS requests. It's fully managed, meaning you don't need to worry about server maintenance, and it scales automatically.
• Supabase: Supabase recently introduced Edge Functions, which are serverless functions running on Deno and V8 isolates. While this is a newer offering, it is gaining traction for its performance and integration with PostgreSQL.

Example: Creating a Serverless Function

• Firebase Cloud Function:

const functions = require('firebase-functions');
exports.addMessage = functions.https.onRequest(async (req, res) => {
  const original = req.query.text;
  const writeResult = await admin.firestore().collection('messages').add({ original });
  res.json({ result: `Message with ID: ${writeResult.id} added.` });
});

• Supabase Edge Function (Deno):

export async function onRequest(context) {
  const data = await context.request.json();
  const { error } = await supabase
    .from('messages')
    .insert({ content: data.content });
  if (error) {
    return new Response('Failed to insert message', { status: 500 });
  }
  return new Response('Message inserted successfully', { status: 200 });
}

When to Choose:

• Choose Firebase if you need a mature, reliable serverless platform that integrates deeply with other Firebase and Google services.
• Choose Supabase if you’re interested in using modern serverless functions with Deno and need tight integration with PostgreSQL.

Pricing and Scalability

• Firebase: Firebase uses a pay-as-you-go pricing model, which can become expensive as your application scales, especially if you heavily use features like Firestore, Cloud Functions, or Cloud Storage.
• Supabase: Supabase also uses a pay-as-you-go model, but being open-source, it allows for self-hosting, which can reduce costs in the long term. Supabase’s pricing is generally considered more predictable, especially if you’re already familiar with PostgreSQL.

When to Choose:

• Choose Firebase if you prioritize ease of use, a fully managed environment, and don’t mind paying for the convenience.
• Choose Supabase if you prefer more control over your costs, possibly through self-hosting, and you’re comfortable managing a PostgreSQL database.

Conclusion: Which One Should You Pick?

• Firebase is an excellent choice for developers looking for a mature, integrated platform with strong support for real-time applications and serverless functions. It’s particularly well-suited for applications that benefit from Google’s ecosystem, such as those requiring robust analytics, machine learning, or cloud services.
• Supabase is ideal for developers who prefer an open-source, SQL-first approach with the flexibility of PostgreSQL. It’s a strong contender for projects that require complex querying, transactional support, or the option to self-host.

In summary, if your project requires a NoSQL database, real-time capabilities, and deep integration with Google Cloud, go with Firebase. If you need a relational database with SQL capabilities, transparency of open-source, and the flexibility of PostgreSQL, Supabase is the better choice. Each platform has its strengths, and the right choice depends on your specific project needs, budget, and technical preferences.