Resumen
Although there are e-health systems for the care of elderly people, the reactive characteristics to enhance scalability and extensibility, and the use of this type of system in smart cities, have been little explored. To date, some studies have presented healthcare systems for specific purposes without an explicit approach for the development of health services. Moreover, software engineering is hindered by agile management challenges regarding development and deployment processes of new applications. This paper presents an approach to develop health Internet of Things (IoT) reactive applications that can be widely used in smart cities for the care of elderly individuals. The proposed approach is based on the Rozanski and Woods?s iterative architectural design process, the use of architectural patterns, and the Reactive Manifesto Principles. Furthermore, domain-driven design and the characteristics of the emerging fast data architecture are used to adapt the functionalities of services around the IoT, big data, and cloud computing paradigms. In addition, development and deployment processes are proposed as a set of tasks through DevOps techniques. The approach validation was carried out through the implementation of several e-health services, and various workload experiments were performed to measure scalability and performance in certain parts of the architecture. The system obtained is flexible, scalable, and capable of handling the data flow in near real time. Such features are useful for users who work collaboratively in the care of elderly people. With the accomplishment of these results, one can envision using this approach for building other e-health services.