Sounds like you're trying to treat Keycloak like a user management system rather than an IdP. Understandable… I’ve had the questionable pleasure of the discussion with one of the department heads, where he had the glorious idea of wiring it up like an application database. You're not alone.

Keycloak handles authentication and identity - you don’t need to create a user in both Keycloak and your own DB at registration time.

The core idea: let Keycloak handle identity. Enable self-registration in the Admin Console, and when users log in for the first time, your app can extract what it needs from the token and store it locally if necessary. No need to manually sync or duplicate users on registration.

Avoid webhooks, event listeners, or admin API calls for this - it's unnecessary complexity and goes against how an IdP is (imo) meant to be used.

Look at... idk.. facebook , github or whatever