1. A computer system comprising the following: one or more processors; system memory; one or more computer-readable storage media having stored thereon computer-executable instructions that, when executed by the one or more processors, causes the computing system to perform a method for managing multiple different types of applications using service groups, the method comprising the following: an act of receiving an indication of one or more application dependencies and characteristics that are to be implemented when an application is provisioned on a distributed host computer system; an act of creating an application manifest that declaratively defines application dependencies and characteristics for each of a plurality of different service groups, such that each service group includes applications that match the declaratively defined application dependencies and characteristics; and an act of sending the manifest to the distributed host computer system which loads those applications that fit the manifest criteria on one or more available nodes of the distributed host computer system according to the service groups specified in the manifest.