The currently available hypermedia support (e.g. LinkDiscoverer, Jackson modules to render HAL etc.) has to be configured manually. So if you'd like to work with HAL as hypermedia format you have to configure the according LinkDiscoverer, customize the ObjectMapper setup etc.
To ease that we should expose an @EnableHypermediaSupport annotation exposing an attribute to configure the supported hypermedia type triggering the registration of the necessary components accordingly.