ZenoAuth vs FusionAuth
Both ZenoAuth and FusionAuth are self-hosted IAM platforms. ZenoAuth eliminates the Elasticsearch dependency, ships as an 11 MB Rust binary, and adds native Verifiable Credential support.
How ZenoAuth and FusionAuth compare on architecture, features, and cost.
| ZenoAuth | FusionAuth | |
|---|---|---|
| Language | Rust | Java |
| Binary Size | 11 MB | ~300 MB |
| Memory Usage | ~50 MB | 512+ MB |
| Dependencies | PostgreSQL only | PostgreSQL + Elasticsearch |
| Verifiable Credentials | Native (OID4VCI + OID4VP) | Not available |
| SCIM v2 | Built-in bidirectional | Community edition limited |
| Pricing (self-hosted) | €5,000/year | Free community / $3,750+/year paid |
| OAuth 2.0 / OIDC | Full | Full |
| MFA | TOTP, WebAuthn, Passkeys | TOTP, SMS, Email |
| Admin UI | Next.js 15 | React |
| Themes | CSS customizable | Full theme engine |
The biggest operational difference: ZenoAuth does not require Elasticsearch.
FusionAuth requires Elasticsearch for its search functionality, adding memory overhead (typically 1-2 GB), operational complexity, and another service to monitor and upgrade. ZenoAuth uses PostgreSQL full-text search and handles all queries within a single database.
ZenoAuth starts in under a second and reaches full performance immediately. No JVM warm-up, no class loading delays, no garbage collection pauses during peak authentication loads.
ZenoAuth is the only self-hosted IAM with native W3C Verifiable Credential support.
Issue W3C Verifiable Credentials in SD-JWT format with selective disclosure via OID4VCI. Users control which claims they reveal during presentation.
Accept Verifiable Presentations from digital wallets via OID4VP as a first-class authentication method. Map credential claims to RBAC roles automatically.
When users are provisioned via SCIM, ZenoAuth automatically generates credential offers. Zero manual steps between HR onboarding and digital wallet provisioning.
FusionAuth is a solid self-hosted platform with its own strengths.
FusionAuth offers a free community edition with core IAM features. If budget is the primary constraint and you do not need SCIM, advanced MFA, or Verifiable Credentials, FusionAuth Community is a zero-cost starting point.
FusionAuth provides a deep theming system with Apache FreeMarker templates, letting you customize every login page, registration form, and email template without forking the codebase.
FusionAuth supports SMS-based OTP and email-based OTP out of the box. If your user base requires SMS as a second factor, FusionAuth has built-in integrations with Twilio and other providers.
The paid Reactor add-on provides advanced threat detection, breached password detection, and advanced registration forms. These are mature, well-tested enterprise features.
One binary. One database. Full IAM. No Elasticsearch cluster to manage.