Firebase Supabase Cognito Comparison: Why I Skipped AWS for My Indie SaaS
When building an indie SaaS, every decision counts. The wrong choice for core infrastructure can mean days lost to configuration, unexpected costs, or a complete rebuild down the line. Authentication is one of those foundational pieces. For my projects, SwitchWithAI and Vitta, I chose Firebase and Supabase for authentication, specifically opting out of AWS Cognito. This wasn't a casual decision; it was about developer velocity, predictable costs, and avoiding the complexity often associated with enterprise-grade solutions when you're a lean builder.
Why is AWS Cognito often a nightmare for indie builders?
AWS Cognito is powerful, no doubt. For large enterprises with dedicated DevOps teams, complex IAM policies, and deep integration into the broader AWS ecosystem, it can be a robust solution. But for a solo founder or a small team trying to ship fast, it often introduces more friction than it solves.
The core issue I've seen, and heard echoed by many other indie builders, is complexity. Setting up a basic user pool in Cognito can feel like navigating a labyrinth of configurations. You're dealing with IAM roles, user pool groups, identity pools, custom authentication flows, and often, Lambda triggers just to get standard functionality working. This isn't just about initial setup; it's about ongoing maintenance and debugging when things go wrong. Every time I've considered it, I've mentally added days to my development timeline just for auth.
Then there's the cost. While AWS has a free tier, Cognito's pricing model can quickly become opaque as you scale or add features like SMS MFA. For an indie SaaS, every dollar counts, and you need a clear understanding of your burn rate. The potential for unexpected charges, especially when integrating with other AWS services that might incur their own costs, makes it a less attractive option for projects where budgets are tight. You're trying to validate a product, not become an AWS expert.
How Firebase simplified authentication for SwitchWithAI and Vitta
For SwitchWithAI, my AI resume tailoring service, and Vitta, my personal finance app, Firebase Authentication was a clear winner for rapid development and ease of use. Both apps are built with Flutter, and Firebase's SDKs integrate seamlessly, allowing me to get user signup, login, and session management up and running in hours, not days.
For example, when I launched Vitta, I had user email/password authentication fully functional in under an hour. In the last 7 days, Vitta saw 61 sessions on its /login path, part of 279 overall sessions. This indicates real user engagement, and Firebase handled all of that authentication traffic without a single hiccup or complex configuration on my end. SwitchWithAI's /login path also saw 61 sessions in the past week, with 20 sessions landing on /pricing. The ability to focus on tailoring AI resumes or parsing SMS bank data, rather than wrestling with auth, was invaluable.
Firebase provides ready-to-use solutions for email/password, social logins (Google, Apple, etc.), and even phone number verification. This "batteries-included" approach means I spend less time wiring up basic auth flows and more time building core product features. The generous free tier is also a huge benefit for an indie builder validating an idea. As my projects grow, the predictable pay-as-you-go pricing model makes it easy to forecast costs.
Here's a simplified Flutter example of how straightforward Firebase Auth can be:
// main.dart - Initialize Firebase
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
void main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp(); // Your firebase_options.dart handles project config
runApp(MyApp());
}
// auth_service.dart
import 'package:firebase_auth/firebase_auth.dart';
class AuthService {
final FirebaseAuth _auth = FirebaseAuth.instance;
// Register with email and password
Future<User?> registerWithEmailAndPassword(String email, String password) async {
try {
UserCredential result = await _auth.createUserWithEmailAndPassword(email: email, password: password);
return result.user;
} catch (e) {
print(e.toString());
return null;
}
}
// Sign in with email and password
Future<User?> signInWithEmailAndPassword(String email, String password) async {
try {
UserCredential result = await _auth.signInWithEmailAndPassword(email: email, password: password);
return result.user;
} catch (e) {
print(e.toString());
return null;
}
}
// Sign out
Future<void> signOut() async {
try {
return await _auth.signOut();
} catch (e) {
print(e.toString());
return null;
}
}
// Get current user stream
Stream<User?> get user {
return _auth.authStateChanges();
}
}
This minimal code snippet is all it takes to get basic user management working, letting me focus on the unique value proposition of SwitchWithAI or Vitta.
When to choose Supabase: My experience with PAIOS
While Firebase is my go-to for many Flutter-first projects, Supabase offers a compelling alternative, especially when you prefer an open-source, PostgreSQL-backed solution. I chose Supabase for PAIOS (Personal AI OS), my project that orchestrates Ollama, n8n, and Supabase for local AI inference.
The main draw for Supabase was its strong SQL foundation and Row Level Security (RLS). For PAIOS, where data privacy and granular control over user-specific AI models and interactions are critical, RLS on a PostgreSQL database provides a robust security layer directly at the database level. This means I can define policies that ensure users can only access their own data, without writing complex backend logic to enforce it.
Supabase Auth is built on top of the PostgreSQL database, leveraging battle-tested patterns. It provides email, magic link, and social logins, much like Firebase. But the real power comes from its integration with PostgreSQL and the ability to manage users and their data within a single, coherent SQL environment. For a backend-heavy project like PAIOS, where I'm dealing with custom data models for AI agents and their outputs, Supabase felt like a more natural fit.
Supabase also offers a generous free tier, and its pricing scales predictably. The fact that it's open-source means I have the flexibility to self-host if I ever need to, offering a level of control that proprietary services often lack.
Here's a quick look at how Supabase Auth might integrate, particularly highlighting RLS:
-- Enable Row Level Security on your table
ALTER TABLE profiles ENABLE ROW LEVEL SECURITY;
-- Create a policy to allow users to see their own profile
CREATE POLICY "Users can view their own profile." ON profiles
FOR SELECT USING (auth.uid() = user_id);
-- Create a policy to allow users to update their own profile
CREATE POLICY "Users can update their own profile." ON profiles
FOR UPDATE USING (auth.uid() = user_id) WITH CHECK (auth.uid() = user_id);
-- Example of a Flutter sign-up with Supabase
// In your Flutter app
import 'package:supabase_flutter/supabase_flutter.dart';
final supabase = Supabase.instance.client;
Future<void> signUpUser(String email, String password) async {
final AuthResponse res = await supabase.auth.signUp(
email: email,
password: password,
);
if (res.user != null) {
print('User signed up: ${res.user!.id}');
// You might insert into a 'profiles' table here
await supabase.from('profiles').insert({'id': res.user!.id, 'email': email});
} else {
print('Sign up error: ${res.session?.user?.email ?? 'Unknown error'}');
}
}
This demonstrates the powerful combination of client-side Flutter code with server-side RLS, making your application inherently more secure and your backend simpler.
Firebase vs. Supabase: A quick decision framework for indie SaaS
Both Firebase