Systems and methods are provided for deriving, based on a service for which an entity is to be selected or provisioned, a query to determine, from candidate nodes, one or more node instances within a topology that fulfill one or more criteria provided by one or more classes; and an additional criterion. The candidate nodes represent respective entities. The evaluation of the query includes determining the classes that satisfy or fulfill the one or more criteria, determining one or more second classes that match, or inherit from, the one or more classes, partially evaluating the additional criterion within respective contexts of the candidate nodes and each of the one or more second classes, based on the partial evaluation, processing the query to determine the node instances, and provisioning or presenting an entity represented by a node instance of the node instances to the service.