ZenoAuth vs Keycloak

Looking for a Keycloak Alternative?

ZenoAuth delivers the same OAuth 2.0 and OpenID Connect capabilities as Keycloak in an 11 MB Rust binary — 27x smaller, with a fraction of the memory footprint and no JVM required.

Side-by-Side Comparison

How ZenoAuth and Keycloak compare across architecture, features, and operations.

ZenoAuth Keycloak
Language Rust Java
Binary Size 11 MB 300+ MB
Memory Usage ~50 MB 500+ MB
External Dependencies PostgreSQL only PostgreSQL + Infinispan (+ optional Redis, LDAP)
Setup Time Minutes Hours
Docker Image ~15 MB ~450 MB
Configuration Environment variables XML + Admin Console
Verifiable Credentials Native (OID4VCI + OID4VP) Not available
SCIM v2 Built-in bidirectional Via extensions
OAuth 2.0 / OIDC Full Full
MFA TOTP, WebAuthn, Passkeys TOTP, WebAuthn
Admin UI Next.js 15 Freemarker templates

What ZenoAuth Does Differently

Architectural decisions that eliminate operational complexity.

Single Binary Deployment

No JVM, no classpath issues, no WAR files. Download one binary, set your environment variables, and start serving authentication requests. Upgrades are a single file swap.

PostgreSQL-Only Architecture

No Redis cluster to manage. No Infinispan cache to tune. ZenoAuth requires exactly one external dependency: PostgreSQL. Fewer moving parts means fewer failure modes.

Native Verifiable Credentials

Issue and verify W3C Verifiable Credentials with SD-JWT selective disclosure, OID4VCI issuance, and OID4VP wallet-based authentication. No other self-hosted IAM ships this natively.

Rust Memory Safety

No garbage collection pauses. No JVM warm-up time. Predictable, low-latency performance from the first request. Memory-safe by design without runtime overhead.

When to Choose Keycloak

Keycloak is a mature, battle-tested platform. Here is where it excels.

Mature Ecosystem

Keycloak has been in production since 2014. It has extensive documentation, hundreds of community extensions, and a large pool of developers familiar with its configuration model.

Red Hat Support

As part of the Red Hat SSO product line, Keycloak offers enterprise support contracts, certified container images, and long-term maintenance releases backed by Red Hat.

Extensive Theme Customization

Keycloak provides a deep theme engine with Freemarker templates covering every login screen, email template, and account management page. Full visual customization without forking.

Battle-Tested at Massive Scale

Organizations with millions of users run Keycloak in production. Its clustering model with Infinispan is proven at scales that few open-source IAM platforms have reached.

Ready to Try Something Lighter?

Deploy ZenoAuth in minutes. Same standards, smaller footprint, simpler operations.

Try ZenoAuth Contact Sales