Keycloak has support for custom event listeners so we can for instance react on:

• user registration (preparing the infrastructure in the inventory)
• user changed it's email (propagate it into current ui session)
• user was removed (some clean up)
  etc.

http://docs.jboss.org/keycloak/docs/1.2.0.CR1/userguide/html/events.html#d4e2235
http://docs.jboss.org/keycloak/docs/1.2.0.CR1/userguide/html/providers.html

I started playing with it here https://github.com/Jiri-Kremser/hawkular-accounts/tree/keycloak-events/keycloak-event-listener, but currently it's basically almost the same code as in here https://github.com/keycloak/keycloak/tree/master/examples/providers/event-listener-sysout