Smart items are physical objects that are enhanced by information technology. There are a number of different smart item technologies available, all of which have different capabilities, protocols, and management functionality. These devices have become an attractive solution for enterprise scenarios. In such scenarios lifecycle management can become a challenge when considering the differences of the smart item types while at the same time providing an abstraction for common functionality. We propose an infrastructure for service lifecycle management of smart items. It is part of a middleware called Smart Item Services Infrastructure (SI)2, which is able to provide a uniform access to various smart item types. The presented architecture addresses the platform heterogenity challenge with a separation of platform-specific and platform-independent functionality. Service Lifecycle Managers for the individual platforms translate the platform-independent requests into the device-specific protocol. Besides platform abstraction, the deployment planning of services is a major requirement. Thus, we put special focus on the Service Mapper component, which determines a deployment plan that satisfies a number of constraints.