OpenID Connect Integration is now Open Source
We are happy to announce that third-party OpenID Connect (OIDC) authentication support has now been open-sourced under the AGPL-3.0 license in Stalwart Mail Server version 0.11.5. This means that users can now configure Stalwart Mail Server to authenticate against external OIDC providers, such as Keycloak, without requiring an Enterprise subscription.
Stalwart Mail Server has supported OIDC authentication for several months, allowing it to function as either an OIDC provider or an OIDC client authenticating against an external provider. Until now, only the ability to act as an OIDC provider was included in the Open Source edition, while authentication via external OIDC providers was reserved for Enterprise users. By making this functionality freely available, we are reinforcing our commitment to openness and ensuring that more users can take advantage of modern, federated authentication without barriers.
With this change, organizations that rely on external OIDC identity providers can seamlessly integrate Stalwart Mail Server into their existing authentication workflows at no cost. Whether you are using Keycloak, Auth0, or another OIDC-compliant solution, Stalwart Mail Server now offers complete flexibility in how you manage authentication.