ComparisonSupabase or Firebase?
Supabase or Firebase?
The real security comparison.
Two dominant SaaS backends, two very different security models. RLS on PostgreSQL versus Firestore Security Rules on NoSQL. Here is what each approach actually protects, and where the most common mistakes show up.
Detailed security comparison
| Criterion | Supabase | Firebase |
|---|---|---|
| Data model | PostgreSQL relational | Firestore NoSQL (documents/collections) |
| Access control | Row Level Security (RLS) in SQL | Security Rules (proprietary language) |
| Granularity | Per row, per column, per operation (SELECT, INSERT, UPDATE, DELETE) | Per document, per collection, per operation |
| Most common mistake | RLS disabled or incomplete (SELECT forgotten) | Overly permissive rules (allow read, write: if true) |
| Authentication | GoTrue (email, OAuth, magic link, phone) | Firebase Auth (email, OAuth, phone, anonymous) |
| Storage | Supabase Storage with RLS policies | Cloud Storage with Security Rules |
| Edge/Cloud Functions | Deno Edge Functions (auth check is manual) | Cloud Functions (auto-authenticated via context) |
| Default exposure | Public anon key in client, RLS required | Public Firebase config, rules required |
| Auditability | SQL policies are versionable and locally testable | Rules sit in the console, testable via emulator |
| Primary risk | PostgreSQL data readable if RLS is missing | Firestore documents open if rules are misconfigured |
| Native security monitoring | PostgreSQL logs, no dedicated security dashboard | Firebase App Check, but opt-in and often missing |
Supabase fits better if...
- Your team is comfortable with SQL and prefers versionable policies
- You need fine-grained control at the row and column level
- Your application has complex relationships between entities
- You want to test your policies locally before deploying
- You are aiming for strict compliance (RLS policies are auditable)
Firebase fits better if...
- Your team is comfortable with the NoSQL model and Security Rules
- You are building a mobile-first application with real-time sync
- You need Firebase anonymous auth for onboarding flows
- Your architecture is simple (few relationships between documents)
- You are already running on the Google Cloud ecosystem