FusionAuth vs Kanidm
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
Kanidm
Modern, simple and secure identity management server
| Feature | FusionAuth | Kanidm |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 70 · Good | 90 · Excellent |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | MPL-2.0 |
| Language | Dockerfile | Rust |
| Setup difficulty | Medium | Medium |
| Min. RAM | 1,024 MB | 256 MB |
| Deployment | docker, kubernetes, bare-metal | docker, binary |
| GitHub stars | ★ 241 | ★ 5,404 |
| First released | 2018 | 2019 |
| Replaces | Auth0, Okta | Active Directory, Okta |
What are FusionAuth and Kanidm?
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
Kanidm
Kanidm is an identity management platform written in Rust, focused on simplicity, security and correctness. It provides authentication for web applications, Unix systems and LDAP-aware services.
- OAuth2 and OpenID Connect provider
- Passkey-first authentication
- Unix and LDAP integration
- Strong security defaults
FusionAuth vs Kanidm: key differences
FusionAuth is written in Dockerfile, while Kanidm is built with Rust. Licensing differs — Apache-2.0 for FusionAuth versus MPL-2.0 for Kanidm. Kanidm is the lighter option, starting around 256 MB of RAM against 1,024 MB for FusionAuth. Kanidm has the considerably larger community, at 5,404 GitHub stars versus 241.
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 Kanidm if…
- Memory safe and lightweight
- Excellent passwordless support
Watch out for
- Smaller ecosystem and tooling
Frequently asked questions
Is FusionAuth or Kanidm better?
Neither is universally better. Kanidm has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are FusionAuth and Kanidm free and open-source?
Yes. FusionAuth is licensed under Apache-2.0 and Kanidm under MPL-2.0. Both can be self-hosted at no software cost.
Can I run FusionAuth and Kanidm with Docker?
FusionAuth: yes. Kanidm: yes.
Which is lighter on resources, FusionAuth or Kanidm?
Kanidm has the smaller minimum footprint at 256 MB of RAM, compared to about 1,024 MB for FusionAuth. Real-world usage depends on library size, user count, and enabled features.