FusionAuth vs Ipsilon
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
FusionAuth
Complete authentication and authorization platform
VS
Ipsilon
Identity provider for federated single sign-on
| Feature | FusionAuth | Ipsilon |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | GPL-3.0 |
| Language | Dockerfile | Python |
| Setup difficulty | Medium | Hard |
| Min. RAM | 1,024 MB | 512 MB |
| Deployment | docker, kubernetes, bare-metal | bare-metal, source |
| GitHub stars | ★ 241 | ★ 80 |
| First released | 2018 | 2014 |
| Replaces | Auth0, Okta | Okta, PingFederate |
What are FusionAuth and Ipsilon?
FusionAuth
FusionAuth is a self-hostable customer identity and access management platform supporting OAuth, OIDC, SAML, MFA, and user management. The community edition runs free on your own infrastructure.
- OAuth, OIDC and SAML support
- Multi-factor authentication
- User and tenant management
- Themable login pages
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
FusionAuth vs Ipsilon: key differences
FusionAuth is written in Dockerfile, while Ipsilon is built with Python. Licensing differs — Apache-2.0 for FusionAuth versus GPL-3.0 for Ipsilon. Ipsilon is the lighter option, starting around 512 MB of RAM against 1,024 MB for FusionAuth. Ipsilon is the more established project (first released 2014), while FusionAuth arrived in 2018. FusionAuth has the considerably larger community, at 241 GitHub stars versus 80. FusionAuth lists first-class Docker deployment; Ipsilon does not.
Why pick each one
Choose FusionAuth if…
- Released under the Apache-2.0 license
- First-class Docker support for quick deployment
- Kubernetes-ready with Helm charts available
- Written in Dockerfile
Choose Ipsilon if…
- Good FreeIPA companion
- Federation focused
Watch out for
- Small community
- Limited recent activity
Frequently asked questions
Is FusionAuth or Ipsilon better?
FusionAuth is the stronger all-round pick: it has both the larger community and the simpler medium setup. Consider Ipsilon if its specific feature set fits your needs better.
Are FusionAuth and Ipsilon free and open-source?
Yes. FusionAuth is licensed under Apache-2.0 and Ipsilon under GPL-3.0. Both can be self-hosted at no software cost.
Can I run FusionAuth and Ipsilon with Docker?
FusionAuth: yes. Ipsilon: check the project docs for container support.
Which is lighter on resources, FusionAuth or Ipsilon?
Ipsilon has the smaller minimum footprint at 512 MB of RAM, compared to about 1,024 MB for FusionAuth. Real-world usage depends on library size, user count, and enabled features.