Apereo CAS vs Dex
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Apereo CAS | Dex |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 93 · Excellent | 90 · Excellent |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | Java | Go |
| Setup difficulty | Hard | Medium |
| Min. RAM | 1,024 MB | 128 MB |
| Deployment | docker, kubernetes, bare-metal | docker, kubernetes, binary |
| GitHub stars | ★ 11,374 | ★ 11,112 |
| First released | 2004 | 2016 |
| Replaces | Okta, Ping Identity | Okta, Auth0 |
What are Apereo CAS and Dex?
Apereo CAS
Apereo CAS is an open-source, enterprise single sign-on solution and identity provider. Widely used in higher education, it supports the CAS protocol along with SAML, OAuth2 and OpenID Connect.
- CAS, SAML, OAuth2 and OIDC protocols
- Multi-factor authentication
- Pluggable authentication handlers
- Delegated and federated authentication
Dex
Dex is an identity service that uses OpenID Connect to drive authentication for other applications. It acts as a portal to other identity providers through connectors such as LDAP, SAML and GitHub.
- OIDC federation broker
- Connectors for LDAP, SAML and GitHub
- Popular in Kubernetes environments
- Lightweight and stateless
Apereo CAS vs Dex: key differences
Apereo CAS is written in Java, while Dex is built with Go. Dex is the lighter option, starting around 128 MB of RAM against 1,024 MB for Apereo CAS. Apereo CAS is the more established project (first released 2004), while Dex arrived in 2016.
Why pick each one
Choose Apereo CAS if…
- Mature SSO with broad protocol support
- Widely adopted in academia
Watch out for
- Configuration is involved
Choose Dex if…
- Great Kubernetes integration
- Simple and reliable
Watch out for
- No user management of its own
Frequently asked questions
Is Apereo CAS or Dex better?
Neither is universally better. Apereo CAS has the larger community, while Dex is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.
Are Apereo CAS and Dex free and open-source?
Yes. Apereo CAS is licensed under Apache-2.0 and Dex under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Apereo CAS and Dex with Docker?
Apereo CAS: yes. Dex: yes.
Which is lighter on resources, Apereo CAS or Dex?
Dex has the smaller minimum footprint at 128 MB of RAM, compared to about 1,024 MB for Apereo CAS. Real-world usage depends on library size, user count, and enabled features.