In a later release of hk2 than is integrated with Jersey (but which will be integrated soon) you can have services that are marked @Immediate. These basically get started as soon as they are added to hk2. However, in order to make it work you will have to add the Immediate context to the system (e.g. https://hk2.java.net/2.2.0-b27/apidocs/org/glassfish/hk2/utilities/ServiceLocatorUtilities.html#enableImmediateScope%28org.glassfish.hk2.api.ServiceLocator%29)
It would be a good idea to lobby with the Jersey team to have this scope/context pair enabled by default (they already enable things like PerThread scope)
I have created this issue: https://java.net/jira/browse/JERSEY-2291 to request that Jersey enable @Immediate services by default