Apereo CAS vs Open Policy Agent
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Apereo CAS
Enterprise single sign-on server for web applications
VS
Open Policy Agent
General-purpose policy engine for cloud-native stacks
| Feature | Apereo CAS | Open Policy Agent |
|---|---|---|
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | Java | Go |
| Setup difficulty | Hard | Medium |
| Min. RAM | 1,024 MB | 256 MB |
| Deployment | docker, kubernetes, bare-metal | docker, kubernetes, binary |
| GitHub stars | ★ 11,354 | ★ 12,086 |
| First released | 2004 | 2016 |
| Replaces | Okta, Ping Identity | AWS IAM policies |
Why pick each one
Choose Apereo CAS if…
- Mature SSO with broad protocol support
- Widely adopted in academia
Choose Open Policy Agent if…
- Released under the Apache-2.0 license
- First-class Docker support for quick deployment
- Kubernetes-ready with Helm charts available
- Mature project with 12.1k GitHub stars
Frequently asked questions
Is Apereo CAS or Open Policy Agent better?
Open Policy Agent is the stronger all-round pick: it has both the larger community and the simpler medium setup. Consider Apereo CAS if its specific feature set fits your needs better.
Are Apereo CAS and Open Policy Agent free and open-source?
Yes. Apereo CAS is licensed under Apache-2.0 and Open Policy Agent under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Apereo CAS and Open Policy Agent with Docker?
Apereo CAS: yes. Open Policy Agent: yes.