From MSDynamicsWorld: Microsoft announces Dynamics GP 2015 Developer Preview, featuring new Service Based Architecture
Microsoft announces Dynamics GP 2015 Developer Preview, featuring new Service Based Architecture | MSDynamicsWorld.com
Development & IntegrationMicrosoft & the GP EcosystemGP 2015
Archived post from 2014. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.