OpenUnison 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 | OpenUnison | Ory Hydra |
|---|---|---|
| Deploy effort | Read-the-docs project | Under-an-hour setup |
| Health score | 67 · Good | 90 · Excellent |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | Less | Go |
| Setup difficulty | Hard | Hard |
| Min. RAM | 1,024 MB | 256 MB |
| Deployment | kubernetes, helm | docker, kubernetes, binary |
| GitHub stars | ★ 136 | ★ 17,563 |
| First released | 2018 | 2015 |
| Replaces | Okta | Okta, Auth0 |
What are OpenUnison and Ory Hydra?
OpenUnison
OpenUnison is an open-source identity manager and single sign-on portal that integrates Kubernetes and applications with enterprise identity providers. It is self-hosted in the cluster.
- Kubernetes SSO portal
- Identity provisioning
- LDAP and SAML integration
- Self-service workflows
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
OpenUnison vs Ory Hydra: key differences
OpenUnison is written in Less, while Ory Hydra is built with Go. Ory Hydra is the lighter option, starting around 256 MB of RAM against 1,024 MB for OpenUnison. Ory Hydra is the more established project (first released 2015), while OpenUnison arrived in 2018. Ory Hydra has the considerably larger community, at 17,563 GitHub stars versus 136. Ory Hydra lists first-class Docker deployment; OpenUnison does not.
Why pick each one
Choose OpenUnison if…
- Released under the Apache-2.0 license
- Kubernetes-ready with Helm charts available
- Written in Less
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 OpenUnison 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 OpenUnison and Ory Hydra free and open-source?
Yes. OpenUnison 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 OpenUnison and Ory Hydra with Docker?
OpenUnison: check the project docs for container support. Ory Hydra: yes.
Which is lighter on resources, OpenUnison or Ory Hydra?
Ory Hydra has the smaller minimum footprint at 256 MB of RAM, compared to about 1,024 MB for OpenUnison. Real-world usage depends on library size, user count, and enabled features.