🔁 How We Migrated a 100K-User App from Supabase to Firebase + GCP (With Zero Downtime)

Supabase is great -- until it isn't.

One of our recent clients, a fast-growing SaaS startup, came to us with this problem:

> "We love Supabase, but now we're hitting performance walls, and managing infra is becoming a bottleneck."

They had:

• 100,000+ active users
• A PostgreSQL-based Supabase setup
• Real-time chat + analytics
• Monthly hosting bills climbing fast

Within 2 weeks, we migrated their entire backend to Firebase + Google Cloud -- with zero user disruption.

Here's how we did it.

📊 Why They Outgrew Supabase

While Supabase is an excellent Firebase alternative for many use cases, here were their main limitations:

🛠️ Step-by-Step Migration Plan

🔹 Step 1: Firestore Schema Design

• Converted relational tables into Firestore collections/subcollections
• Designed with shallow reads and denormalization
• Indexed every query in advance

🔹 Step 2: Auth Migration

• Exported user data from Supabase Auth
• Migrated to Firebase Authentication (email/password + Google sign-in)
• Rewrote auth rules and JWT logic

🔹 Step 3: Real-time Features

• Replaced Realtime Channels with Firestore snapshot listeners
• Used Cloud Functions for server-side triggers

🔹 Step 4: Background Jobs

• Moved cron jobs to Cloud Tasks + Pub/Sub
• Introduced retry + exponential backoff

🔹 Step 5: Analytics

• Plugged user events into GA4 + BigQuery for instant insights
• Created custom dashboards for churn & retention

🔹 Step 6: Zero Downtime Strategy

• Ran Firebase + Supabase in parallel for 2 days
• Used a syncing script to dual-write
• Switched traffic over at midnight using DNS + version flag

📈 Results After Migration

🎯 Client Feedback:

> "This was the smoothest migration we've ever done. Our app is faster, cheaper, and easier to manage. Huge thanks to the team!"

🧠 Should You Migrate?

You should consider switching from Supabase to Firebase + GCP if:

• You need auto-scaling real-time DB without managing Postgres
• You want built-in analytics and cloud-native AI
• You're tired of devops and want a serverless backend
• You're scaling past 10K+ daily users

💼 Work With Us

We specialize in complex backend migrations, especially:

• Supabase → Firebase
• Firebase → GCP hybrid
• Monolith → Microservices

You get:

• ✅Migration plan
• ✅Firestore schema design
• ✅Cloud Run/API setup
• ✅Zero-downtime strategy
• ✅Testing & post-launch support

📞 Ready to Migrate?

> Let's talk about your app. We'll review your stack and show you how to scale it without stress.