# Deploy Cerbos on Fly.io

Deploy the Cerbos PDP on Fly.io for low-latency authorization decisions close to your users across multiple regions.

### Multi-region
Deploy Cerbos instances close to your users across Fly.io regions for low-latency authorization decisions.

### Stateless scaling
Scale horizontally across regions with no coordination; each instance loads policies independently.

### Simple deployment
Define a fly.toml and deploy with a single command using the official Cerbos container image.

## What is Cerbos?
Cerbos is an open-source authorization layer that decouples access control from your application code. It runs as a stateless Policy Decision Point (PDP) that evaluates fine-grained policies at request time.

Authorization policies are written in human-readable YAML supporting [RBAC](/content/features-benefits-and-use-cases/rbac/index.html), [ABAC](/content/features-benefits-and-use-cases/abac/index.html), and [conditional rules](/content/features-benefits-and-use-cases/pbac/index.html). They can be updated, tested, and deployed independently of your application.

Deploying Cerbos via Fly.io gives you a production-ready authorization service that scales horizontally and fits naturally into your existing infrastructure and observability stack.

### How to deploy Cerbos on Fly.io
1. **Create a fly.toml:** Define your Fly.io app configuration referencing the official Cerbos container image and exposing the HTTP and gRPC ports.
2. **Configure policy loading:** Set environment variables or mount a config file to point Cerbos at a Git repository or Cerbos Hub for policies.
3. **Deploy:** Run `fly deploy` to launch the Cerbos PDP on Fly.io infrastructure.
4. **Scale to regions:** Use `fly scale count` and `fly regions add` to place Cerbos instances close to your users.

## FAQ
### How do I deploy Cerbos on Fly.io?
Create a fly.toml that references the official Cerbos container image, configure your policy source, and run `fly deploy`. Cerbos runs as a stateless service that Fly.io can place in any region.

### Can I run Cerbos in multiple Fly.io regions?
Yes. Because Cerbos is stateless, you can scale to multiple regions with `fly scale count`. Each instance loads policies independently from Git or Cerbos Hub.

### Does Cerbos require any external dependencies?
No. Cerbos requires no database or message queue. Policies can be loaded from a Git repository or Cerbos Hub, both of which work well with Fly.io deployments.

## Cerbos + Fly.io
- Cerbos runs alongside your workloads in Fly.io.
- No external databases or message queues required.
- Built-in metrics, distributed tracing, and structured logging.
- Stateless PDP instances scale horizontally.