Firebase Started Eating Our Money, So We Switched to Supabase

The Day Firebase Costs Went Insane

February invoice was over three grand. Previous month was like $180, maybe $200. I stared at this shit for twenty minutes thinking we got cryptojacked or someone was running crypto miners through our chat feature. Nope, just users actually using the app we built.

The Firebase Cost Problem: Real-time listeners go fucking nuts reading way more data than you expect. Every user connection triggers document reads, and every data change forces re-reading entire result sets for all connected clients.

Turns out all our real-time listeners were going absolutely crazy, reading way more data than we expected. Firebase charges you more the more successful you get, which is backwards as hell. Seriously, check out this Firebase billing horror story from 2 days of usage.

That was the wake-up call. Time to figure out what else is out there.

The NoSQL Hell We Built Ourselves

Here's what nobody tells you about Firebase: starts great, turns into a horror movie.

We started simple - users, posts, comments. Typical shit. Two years later I'm looking at a user's name scattered across 14 different collections because Firebase can't do relationships worth a damn.

User changes their name from "John" to "Johnny"? Hope you remembered to update it in posts, comments, notifications, analytics, user_profiles, group_members, activity_feed, user_settings, and six other places. Miss one? Congratulations, your app now shows "Johnny" in the header and "John" in the comments. Users love that shit.

PostgreSQL just laughs at this problem. Foreign keys, joins, constraints - you know, the shit databases have been doing since the 90s.

SQL vs NoSQL Reality: In Firebase, updating a user's name means hunting down 12+ collections and hoping you don't miss any. In PostgreSQL, you update one table and foreign keys handle the rest automatically.

Firebase Security Rules: The Seventh Circle of Hell

Our Firebase security rules file is like 800+ lines of pure terror. Nobody on the team will touch it. Someone tried to add permissions for the reporting feature and accidentally locked out all admins because one nested condition was backwards.

Every rule change is Russian roulette with your production database.

Technical Gotcha: Firebase security rules have a 256KB size limit and 10-depth nesting limit. Hit both limits multiple times debugging complex permission hierarchies.

// This is actual production Firebase rules code that nobody dares touch
allow read, write: if request.auth != null 
  && resource.data.teamId in request.auth.token.teamIds
  && (request.auth.uid == resource.data.createdBy 
      || request.auth.token.admin == true
      || exists(/databases/$(database)/documents/teams/$(resource.data.teamId)/members/$(request.auth.uid)))
  && request.resource.data.keys().hasAll(['title', 'createdBy', 'teamId'])
  && request.resource.data.title.size() > 0
  && request.resource.data.title.size() <= 100;

Meanwhile in PostgreSQL, Row Level Security does the same thing in like 3 lines of readable SQL.

The Breaking Point

The final straw wasn't even the money. It was trying to build a simple analytics dashboard for our CEO.

"How many posts were created last week?"

Firebase: Read all posts. Filter client-side. Hope your lambda doesn't timeout. Cache the results. Build a whole microservice for counting. Maybe sacrifice a goat.

PostgreSQL: SELECT COUNT(*) FROM posts WHERE created_at > now() - interval '7 days'

I rage-quit that day and started researching Supabase.

Real-Time Features That Cost Real Money

Firebase's real-time stuff is slick, I'll give them that. But holy shit is it expensive.

Every time someone opens your app, boom - another listener. Every time data changes, boom - reread everything for everyone. Our notification system was reading the same data thousands of times per day because Firebase has to re-fetch entire result sets when connections drop.

Supabase's real-time is built on PostgreSQL's native features, so you're not getting gouged for basic database operations.

Why We Actually Started Looking at Alternatives

Look, Firebase isn't terrible. It's great for simple apps, prototypes, or if you're building something that doesn't need complex queries. But we hit these walls:

1. Costs became unpredictable - One viral post could bankrupt us
2. Data modeling became a nightmare - NoSQL felt like coding with one hand tied behind our back
3. Security rules turned into spaghetti code - Nobody dared touch them
4. Analytics were impossible - Want to count users? Good fucking luck

The moment I knew we were fucked was when implementing "most popular posts this week" took someone on the team three full days. Three fucking days! In PostgreSQL it's literally ORDER BY like_count DESC LIMIT 10. In Firebase it's cloud functions, denormalized data, scheduled aggregations, and praying nothing breaks.

That's when I started the migration planning.

Next up: what actually happens when you try to migrate this mess.

First Couple Weeks: "This Should Be Straightforward"

Famous last words: "This should be straightforward." We budgeted four weeks. Took way longer - like three or four months - and almost killed the company because nothing worked right for months.

Started by auditing our data model. Turned out our "simple" 8 Firebase collections were actually a tangled mess of implicit relationships. Users had posts, posts had comments, comments had likes, likes had users. None of this was properly normalized because NoSQL lets you get away with murder.

Spent the first week or two just drawing diagrams of what our data actually looked like. It was way worse than we thought.

Next Month: Data Model Hell

Designing a proper PostgreSQL schema from Firebase documents is like untangling Christmas lights while drunk. Everything is connected to everything.

Our Firebase user document looked like this:

{
  uid: "abc123",
  email: "user@email.com",
  profile: {
    name: "John Doe",
    bio: "...",
    avatar: "gs://bucket/avatar.jpg"
  },
  settings: {
    theme: "dark",
    notifications: true
  },
  stats: {
    posts: 42,
    followers: 123
  }
}

In PostgreSQL, this became 4 separate tables with proper foreign keys. Which is correct, but meant rewriting every single query in our app.

OK, quick technical break: Supabase is built on PostgreSQL + PostgREST for auto-generated APIs + GoTrue for auth + Kong for API gateway. Every component is open source and self-hostable, unlike Firebase's proprietary stack.

The Endless Query Rewrite Phase

Every. Single. Firebase. Query. Had. To. Be. Rewritten.

Firebase query:

// Get user's posts with like counts
const postsRef = collection(db, 'posts');
const q = query(postsRef, where('userId', '==', currentUser.uid));
// Then manually count likes for each post in a loop

Supabase equivalent:

-- Get user's posts with like counts in one query
SELECT p.*, COUNT(l.id) as like_count 
FROM posts p 
LEFT JOIN likes l ON p.id = l.post_id 
WHERE p.user_id = $1 
GROUP BY p.id

The SQL is way cleaner, but we had hundreds of these Firebase queries scattered throughout our codebase.

When Real-Time Features Became a Nightmare

Firebase real-time listeners are pretty magical - they just work. Supabase real-time subscriptions... work differently.

Firebase approach:

// This just worked
onSnapshot(collection(db, 'posts'), (snapshot) => {
  setPosts(snapshot.docs.map(doc => doc.data()));
});

Supabase approach:

// This is more verbose and breaks in weird ways
const channel = supabase
  .channel('posts-changes')
  .on('postgres_changes', 
    { event: '*', schema: 'public', table: 'posts' },
    (payload) => {
      // Handle insert/update/delete manually
      handleRealtimeChange(payload);
    }
  )
  .subscribe();

Spent two weeks debugging edge cases where subscriptions would randomly stop working or miss updates. Eventually got it stable, but Firebase's real-time is definitely more mature.

Real Bug That Almost Killed Us: Supabase real-time subscriptions just stop working at some connection limit per channel. No error, no warning, just silence. Spent most of a Friday thinking our code was broken. Bunch of angry users in support complaining chat wasn't updating. This was some version of Supabase and probably still happens.

Platform gotcha: Safari iOS 15.x completely ignores Supabase real-time because of WebSocket bullshit. Half our iPhone users couldn't see live updates for a week. Apple changed some security policy and nobody documented the workaround. Found the fix on a random GitHub comment at 2am.

Auth Migration Was Its Own Special Hell

Firebase Auth to Supabase Auth should be straightforward. It's not.

The APIs are similar, but the session handling is different. Users kept getting logged out randomly during the migration period when we had both systems running.

Our solution was to run both auth systems in parallel and sync sessions manually until we could fully cut over. Worked but felt janky.

The Bugs We Didn't Expect

PostgreSQL is Stricter: Firebase let us store {timestamp: new Date()} and {timestamp: "2023-01-01"} in the same field. PostgreSQL said "fuck that" and errored out. Had to clean up 2 years of inconsistent data.

Data Consistency Reality: PostgreSQL's type system caught dozens of data inconsistencies that Firebase silently allowed. Painful during migration, but prevented future bugs.

Case Sensitivity: Firebase collections are case-insensitive. PostgreSQL table names are case-sensitive. Spent a day tracking down queries that failed because we wrote Users instead of users.

Connection Limits: Firebase handles connections automatically. PostgreSQL has connection limits. Our app would randomly fail to connect during traffic spikes until we set up connection pooling.

The Error That Ruined My Weekend: FATAL: remaining connection slots are reserved for non-replication superuser connections

This showed up every Friday afternoon like clockwork because that's when people actually used our app. Perfect timing to fuck up the weekend. Too many concurrent connections and PostgreSQL just gives up. Firebase handled way more connections like nothing. Fix: spend more money on dedicated instances or learn about connection pooling the hard way on weekends.

Node.js Version Hell: Our Firebase Cloud Functions were running Node 16. Supabase Edge Functions need Deno. Half our serverless functions had to be rewritten because of platform differences. Took us 2 weeks we didn't budget for.

What Actually Got Better

Queries That Make Sense: Analytics dashboards that took 30 seconds on Firebase (reading thousands of documents) now run in 200ms with proper SQL queries.

Predictable Costs: Firebase bill was $200-1200/month depending on traffic. Supabase is $25/month, period. I sleep better now.

Proper Relationships: Foreign keys prevent the data inconsistency bugs we had with Firebase's loose document model.

What Got Worse

Mobile Offline: Firebase offline support just works. Supabase offline is basic and requires way more manual work.

Real-time Complexity: Firebase real-time is more reliable out of the box. Supabase real-time requires more careful engineering.

Learning Curve: Half our team had never written SQL. They picked it up, but it slowed us down for months.

The Honest Cost Assessment

We're probably saving like eight or nine hundred a month with Supabase vs Firebase, but the migration took 3 developers about 3 months. That's probably like forty-something grand in dev time.

Real Numbers: Our Firebase bill was averaging around $400/month with spikes over a grand. Supabase costs us $25/month on the Pro plan. Savings are decent once fully migrated.

Break-even is years out, which is longer than most startups plan for. But the predictable costs and better developer experience make it worth it for us.

Would We Do It Again?

Yeah, probably. But not because it's a slam dunk - because Firebase's pricing model is fundamentally broken for growing apps. One viral feature can bankrupt you.

Supabase isn't perfect, but it's more predictable. And PostgreSQL beats NoSQL for complex queries every single time.

Just budget 3x whatever you think it'll take. I've never seen one of these migrations finish on time. Never.

My Honest Take After Three Months of Hell

I've been through this twice and watched four other teams attempt it.

Here's who should migrate and who should keep paying Google's ransom.

You Should Probably Migrate If:

Firebase is bleeding you dry:

If you're getting surprise invoices over three grand like we were, migrate now before it gets worse. Our February bill was literally more than our rent. Supabase pricing is boring and predictable, which is exactly what you want from infrastructure costs.

You need complex queries:

If you're doing client-side joins because Firebase can't handle relationships, PostgreSQL will change your life. Analytics dashboards that took forever on Firebase run in milliseconds on Supabase.

Your team knows SQL:

If your developers are comfortable with databases, they'll be way more productive with PostgreSQL than Firebase's weird query limitations.

You hate vendor lock-in:

Firebase is Google's playground.

If Google decides to kill Firebase (like they've killed dozens of other products), you're fucked. Supabase is open source

• you have options.

Open Source vs Proprietary:

Firebase = Google's black box, zero portability. Supabase = standard Postgre

SQL you can export, self-host, or migrate anywhere. Huge difference for long-term business continuity.

You Should Definitely Stay with Firebase If:

You're mobile-first: Firebase's mobile SDKs and offline sync are still better.

If most of your users are on i

OS/Android and need offline functionality, stick with Firebase.

Your app is simple: If you're building a basic CRUD app with straightforward data, Firebase's simplicity is actually a feature.

Don't migrate just because it's trendy.

Your team is all frontend: If nobody on your team knows SQL and you don't have time to learn, Firebase's NoSQL approach might actually be better for you.

You're broke:

This migration will eat 3-4 months of development time minimum. If you're cash-strapped, ship features instead. Database migrations don't get you customers. I learned this the hard way when our competitor shipped two major features while we were fucking around with SQL schemas.

Or Just Do Both

You don't have to migrate everything at once. Some teams do hybrid approaches:

• Keep Firebase for user-facing stuff, use Supabase for admin dashboards
• New features on Supabase, legacy stuff stays on Firebase
• Use Postgre

SQL for analytics, keep Firebase for real-time features

This lets you get the benefits of SQL for complex queries without the full migration pain.

What I Learned From This Nightmare

Plan Your Data Model or Die

The biggest mistake is rushing the schema design. Firebase lets you store garbage data because NoSQL is forgiving. PostgreSQL will tell you to fuck off if your data doesn't make sense.

Spend weeks planning your tables and relationships.

It's boring but critical.

Real-Time Features Will Break Your Brain

Firebase real-time listeners are magic. Supabase real-time subscriptions are... more manual.

Budget way more time for this than you think. Every team I know underestimated real-time migration by at least 2x.

Timeline Reality Check: Told the team real-time would take a couple weeks.

Took way longer because Supabase real-time kept breaking in ways I didn't expect. Mobile users would background the app and subscriptions would just die. No error messages, just broken chat and pissed off users.

SQL Knowledge Matters

If your team doesn't know SQL, you're going to struggle.

Either hire someone who does or plan for a long learning curve.

But once your team gets comfortable with PostgreSQL, they'll be way more productive than they ever were with Firebase.

Don't Just Port Queries

The teams that see big cost savings don't just copy their Firebase queries to Postgre

SQL.

They redesign their data access to use SQL properly.

Joins, aggregations, views

• use PostgreSQL like a database, not like a document store.

Why Everyone's Talking About This Migration

Supabase has gotten a lot better in the past year. It feels production-ready now in ways it didn't before.

Market Reality: Supabase went from nobody to a shitload of Git

Hub stars while Firebase barely gets updates anymore.

Google's treating Firebase like a maintenance-mode product while Supabase ships new features every month.

Firebase feels like legacy tech at this point. When's the last time they shipped something exciting? Meanwhile Supabase keeps adding shit I actually want to use.

Plus, a lot of developers are rediscovering that SQL is actually pretty great once you get past the learning curve. NoSQL was trendy, but for complex apps, relational databases just work better.

When You'll Break Even

Don't expect immediate savings. You'll be paying for both platforms during migration and burning developer time.

For us:

• First few months:

Burning money (paying Firebase + Supabase + developer salaries)

• Middle of migration: Sync bug crashed the app for hours, cost us customers and my sanity
• Later months:

Finally stopped paying Firebase, started seeing actual savings

• Eventually: Worth it, but fuck was it expensive getting here

Most teams break even somewhere around 6-12 months, depending on how bad their Firebase bills were.

The Decision Checklist

Migrate if:

• Firebase bills are unpredictable and scary
• You need complex queries that Firebase can't handle
• Your team knows SQL or has time to learn it
• You can spare 3-6 months for this project
• You don't trust Google to keep supporting Firebase long-term

Stay with Firebase if:

• Your app is mostly mobile with offline requirements
• Firebase costs are stable and reasonable
• Your team is all frontend developers who hate databases
• You're using a ton of Google Cloud services
• Your app is simple and Firebase works fine

My Final Recommendation

Don't migrate because Supabase is trendy. Migrate because Firebase is actively fucking you over with unpredictable costs or impossible queries.

If Firebase works fine and your bills are reasonable, stay put. This migration is not a fun weekend project

• it's months of pain that might not be worth it.

But if you're getting invoice panic attacks or spending days implementing simple queries, then yeah, Supabase is probably worth the suffering.

Start with one new feature on Supabase to test the waters. If your team doesn't hate it and the performance is decent, then maybe consider the full migration.

Don't bet the company on a database switch. Test first, migrate second.