Supabase vs Firebase: security comparison for SaaS
> TL;DR: Which backend is more secure? Supabase RLS vs Firebase rules — strengths, weaknesses and pitfalls.
Two fundamentally different security approaches
Supabase: PostgreSQL with Row Level Security policies — SQL rules at the database level.
Firebase: Firestore Security Rules — declarative language in a JSON file.
Supabase: strengths and weaknesses
Strengths: SQL granularity, per-table/operation policies, custom functions.
Weaknesses: configuration complexity, silent errors, RPC functions bypassing RLS.
Firebase: strengths and weaknesses
Strengths: simple syntax, abundant documentation.
Weaknesses: no joins in rules, request.auth != null gives false security, no per-field policy.
Verdict
Supabase offers better security if correctly configured. Firebase is easier but errors are more subtle. Either way, a external review reveals flaws in hours.
Key Takeaways
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Sources
Editorial analysis based on official vendor, project, and regulator documentation.
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