Casdoor vs Gluu Flex
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Casdoor | Gluu Flex |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 94 · Excellent | 69 · Good |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | Go | TypeScript |
| Setup difficulty | Medium | Hard |
| Min. RAM | 256 MB | 4,096 MB |
| Deployment | docker, kubernetes, binary | docker, kubernetes, helm |
| GitHub stars | ★ 14,459 | ★ 31 |
| First released | 2021 | 2009 |
| Replaces | Auth0, Okta | Okta, Ping Identity |
What are Casdoor and Gluu Flex?
Casdoor
Casdoor is an open-source identity and access management platform with a strong focus on a friendly user interface. It supports OAuth2, OIDC, SAML, CAS, LDAP and many social login providers.
- Supports OAuth, SAML, CAS and LDAP
- Dozens of built-in social login providers
- Multi-tenant organization support
- Web-based admin and login UI
Gluu Flex
Gluu provides a self-hostable identity platform for single sign-on, multi-factor authentication, and access management built on open standards. It supports OAuth, OIDC, SAML, and FIDO2.
- Single sign-on
- OAuth, OIDC and SAML
- FIDO2 strong authentication
- Kubernetes deployment
Casdoor vs Gluu Flex: key differences
Casdoor is written in Go, while Gluu Flex is built with TypeScript. Casdoor is the lighter option, starting around 256 MB of RAM against 4,096 MB for Gluu Flex. Gluu Flex is the more established project (first released 2009), while Casdoor arrived in 2021. Casdoor has the considerably larger community, at 14,459 GitHub stars versus 31.
Why pick each one
Choose Casdoor if…
- Polished out-of-the-box UI
- Broad protocol support
Watch out for
- Documentation can be uneven
Choose Gluu Flex if…
- Released under the Apache-2.0 license
- First-class Docker support for quick deployment
- Kubernetes-ready with Helm charts available
- Written in TypeScript
Frequently asked questions
Is Casdoor or Gluu Flex better?
Casdoor is the stronger all-round pick: it has both the larger community and the simpler medium setup. Consider Gluu Flex if its specific feature set fits your needs better.
Are Casdoor and Gluu Flex free and open-source?
Yes. Casdoor is licensed under Apache-2.0 and Gluu Flex under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Casdoor and Gluu Flex with Docker?
Casdoor: yes. Gluu Flex: yes.
Which is lighter on resources, Casdoor or Gluu Flex?
Casdoor has the smaller minimum footprint at 256 MB of RAM, compared to about 4,096 MB for Gluu Flex. Real-world usage depends on library size, user count, and enabled features.