Edge computing is the emerging paradigm that pervasively brings computing in the environment, by shifting processing from data centers to the network edge, allowing a large class of applications in growing fields, like Big Data and the Internet of Things, to be deployed in a very effective way. In this paper, we propose middleware for running applications over heterogeneous environments made of telecom networks and legacy data centers. We briefly review an emerging architecture for edge computing and describe an integrated solution for developing and deploying modular applications in an automatic way.