@Sanne unless I am mistaken or don't remember my intend, you don't need to expose Serializer or performOperations. These are implemented by the AsbtractJMSHibernateSearchController which is an Hibernate Search class, not a user class.

org.hibernate.search.test.integration.jms.controller.RegistrationMdb is what is exposed to the user basically.

The subclass (implemented by the user) needs today to provide SearchIntegrator, the idea is that they would need to provide SearchFactory instead.