Gluu Flex vs Ory Hydra
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Gluu Flex | Ory Hydra |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 69 · Good | 90 · Excellent |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | TypeScript | Go |
| Setup difficulty | Hard | Hard |
| Min. RAM | 4,096 MB | 256 MB |
| Deployment | docker, kubernetes, helm | docker, kubernetes, binary |
| GitHub stars | ★ 31 | ★ 17,563 |
| First released | 2009 | 2015 |
| Replaces | Okta, Ping Identity | Okta, Auth0 |
What are Gluu Flex and Ory Hydra?
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
Ory Hydra
Ory Hydra is an OpenID Certified OAuth 2.0 and OpenID Connect provider. It is built to integrate with any existing identity system and issues tokens without managing user accounts itself.
- OpenID Certified implementation
- Low memory footprint
- Bring your own login and consent UI
- Scales horizontally
Gluu Flex vs Ory Hydra: key differences
Gluu Flex is written in TypeScript, while Ory Hydra is built with Go. Ory Hydra 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 Ory Hydra arrived in 2015. Ory Hydra has the considerably larger community, at 17,563 GitHub stars versus 31.
Why pick each one
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
Choose Ory Hydra if…
- Security focused and certified
- Integrates with any user store
Watch out for
- Only handles OAuth, not user management
Frequently asked questions
Is Gluu Flex or Ory Hydra better?
Neither is universally better. Ory Hydra has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.
Are Gluu Flex and Ory Hydra free and open-source?
Yes. Gluu Flex is licensed under Apache-2.0 and Ory Hydra under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Gluu Flex and Ory Hydra with Docker?
Gluu Flex: yes. Ory Hydra: yes.
Which is lighter on resources, Gluu Flex or Ory Hydra?
Ory Hydra 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.