ZITADEL
API-first identity and access management platform for applications
14.9k stars 1.3k forks last commit first released AGPL-3.0
Actively maintained
Last commit 26 Aug 2026.
ZITADEL is an identity and access management platform for authenticating users and securing applications. It provides hosted and custom login options, supports modern standards like OIDC/OAuth2 and SAML, and is designed with multi-tenancy in mind for B2B and CIAM scenarios.
Key Features
- Multi-tenant organizations with team and project management
- Single Sign-On with OpenID Connect and OAuth 2.x flows
- SAML 2.0 support for enterprise federation
- Multifactor authentication (OTP) and passkeys (FIDO2/WebAuthn)
- Role-based access control (RBAC) and permission management
- Self-service user registration and account management
- API-first platform with gRPC and REST APIs
- SCIM 2.0 server for automated user provisioning
- Event-sourced architecture with an audit trail
Use Cases
- Centralized authentication for web and mobile apps using OIDC/OAuth2
- B2B SaaS user management with isolated organizations and delegated admin
- Enterprise integrations via SAML and automated provisioning via SCIM
Limitations and Considerations
- Requires PostgreSQL (commonly version 14+) as the primary storage backend
ZITADEL combines standards-based authentication with strong multi-tenancy and extensibility, making it suitable for both customer-facing and internal identity scenarios. It can be operated with a hosted login or integrated more deeply via APIs for fully custom experiences.
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