In the last years a new computing paradigm called Internet of Things (IoT) has been gaining more attention. This paradigm has become popular by embedding mobile network and processing capability into a wide range of physical computing devices used in everyday life of many people. An important part that composes the IoT is the middleware, which is a system that abstracts the management of physical devices and provides services based on the information of these devices. Context-aware is an important feature of IoT middleware systems. This feature allows to discover, understand, and store relevant information related to devices and their respective events. In this sense, this work aims to present an ongoing system that has been developed to provide services of contextualized information about IoT devices in heterogeneous environments.