BeanClass attribute of beans is used by Weld to determine how and where to define a proxy class. In WFLY, it is used to determine a module whose CL is then used.

Default beanClass for synthetic beans is always their extension class. It can be arbitrary class but using this interface means that Weld will try to create the proxy under Jakarta API module which has no Weld dependencies and that will trigger a WARN message, see WFLY-17086 .

Related WFLY issue - https://issues.redhat.com/browse/WFLY-17086
Original WFLY PR - wildfly/wildfly#16155