Fly.io + PostgreSQL Security
Fly.io's managed Postgres runs alongside your apps at the edge. Learn how to secure this powerful combination.
Why Fly.io + PostgreSQL?
Fly Postgres provides regional databases that run close to your applications. The distributed nature requires understanding its security model.
Common Vulnerabilities
These are the security issues we find most often in Fly.io apps using PostgreSQL.
Public Postgres Exposure
Postgres may be exposed publicly when it should only be accessible via private networking.
Secrets in fly.toml
Database credentials may be in configuration files instead of fly secrets.
Shared Database Across Environments
Development and production apps may share the same Postgres instance.
Missing SSL Requirement
Applications may connect without requiring SSL encryption.
What We Check for Fly.io + PostgreSQL
Network Exposure
Verify Postgres is only accessible via private networking.
Secrets Management
Check that credentials are in fly secrets, not in code.
Connection Security
Verify SSL is required for all database connections.
Environment Isolation
Check that production data is isolated from other environments.
Quick Security Wins
Apply these fixes right now to improve your security.
Use internal connection string: postgres://...@[app].internal:5432Move credentials to fly secrets: fly secrets set DATABASE_URL=...Create separate Fly Postgres instances for prod/stagingAdd sslmode=require to connection stringsAllocate Postgres to private IPs onlyThe Bottom Line
Fly.io + Postgres is secure when using private networking and fly secrets. Keep your database off the public internet.
Secure Your Fly.io + PostgreSQL App
Find Row Level Security misconfigurations, exposed credentials, and other vulnerabilities before attackers do.
Start Security ScanFrequently Asked Questions
How do I prevent my Fly Postgres from being publicly accessible?
Use internal addresses (app-name.internal) for connections from Fly apps. Don't allocate public IPs to your Postgres app. If you need external access for tools, use fly proxy instead of public exposure.
Where should I store Postgres credentials on Fly.io?
Use fly secrets for all database credentials: fly secrets set DATABASE_URL=postgres://... Never put credentials in fly.toml or your code. Secrets are encrypted and only exposed to your running instances.
Should I use the same Fly Postgres for all environments?
No, create separate Postgres instances for production and development. Use fly postgres create to make isolated instances. This prevents development access to production data and allows safe testing.
How do I connect securely to Fly Postgres from outside Fly?
Use fly proxy postgres rather than exposing Postgres publicly: fly proxy 5432 -a your-postgres-app. This creates a secure tunnel from your local machine. Never allocate public IPs to your database in production.