In smart spaces such as smart homes, computation is embedded everywhere: in toys, appliances, or the home’s infrastructure. Most of these devices provide a pool of available resources which the user can take advantage, interacting and creating a friendly environment. The inherent composability of these systems and other unique characteristics such as low-cost energy, simplicity in module programming, and even their small size, make them a suitable candidate for dynamic and adaptive ambient systems. This research work focuses on what is defined as an “ambience”, a space with a user-defined set of computational devices. A smart-home is modeled as a collection of ambiences, where every ambience is capable of providing a pool of available resources to the user. In turn, the user is supposed to carry one or several personal devices able to interact with the ambiences, taking advantage of his inherent mobility. In this way, the whole system can benefit from resources discovered in the spatial proximity. A software architecture is designed, which is based on the implementation of low-cost algorithms able to detect and update the system when changes in an ambience occur. Ambience middleware implementation works in a wide range of architectures and OSs, while showing a negligible overhead in the time to perform the basic output operations.