Ipsilon vs OpenUnison
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Ipsilon | OpenUnison |
|---|---|---|
| Deploy effort | Read-the-docs project | Read-the-docs project |
| Category | Identity & SSO | Identity & SSO |
| License | GPL-3.0 | Apache-2.0 |
| Language | Python | Less |
| Setup difficulty | Hard | Hard |
| Min. RAM | 512 MB | 1,024 MB |
| Deployment | bare-metal, source | kubernetes, helm |
| GitHub stars | ★ 80 | ★ 136 |
| First released | 2014 | 2018 |
| Replaces | Okta, PingFederate | Okta |
What are Ipsilon and OpenUnison?
Ipsilon
Ipsilon is an identity provider service that supports SAML and OpenID for federated single sign-on. It plugs into existing authentication backends like FreeIPA to centralize login for web applications.
- SAML identity provider
- OpenID support
- FreeIPA integration
- Pluggable backends
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
Ipsilon vs OpenUnison: key differences
Ipsilon is written in Python, while OpenUnison is built with Less. Licensing differs — GPL-3.0 for Ipsilon versus Apache-2.0 for OpenUnison. Ipsilon is the lighter option, starting around 512 MB of RAM against 1,024 MB for OpenUnison. Ipsilon is the more established project (first released 2014), while OpenUnison arrived in 2018.
Why pick each one
Choose Ipsilon if…
- Good FreeIPA companion
- Federation focused
Watch out for
- Small community
- Limited recent activity
Choose OpenUnison if…
- Released under the Apache-2.0 license
- Kubernetes-ready with Helm charts available
- Written in Less
Frequently asked questions
Is Ipsilon or OpenUnison better?
Neither is universally better. OpenUnison has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.
Are Ipsilon and OpenUnison free and open-source?
Yes. Ipsilon is licensed under GPL-3.0 and OpenUnison under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Ipsilon and OpenUnison with Docker?
Ipsilon: check the project docs for container support. OpenUnison: check the project docs for container support.
Which is lighter on resources, Ipsilon or OpenUnison?
Ipsilon has the smaller minimum footprint at 512 MB of RAM, compared to about 1,024 MB for OpenUnison. Real-world usage depends on library size, user count, and enabled features.