The current trends in the automotive industry are towards equipping vehicles with multi-modal connectivity while simultaneously enabling advanced automated functions. These capabilities and their challenges provide OEMs with opportunities to leverage advancements in distributed computing technologies to provide new Mobility Services to customers. In particular, Edge Computing (EC) is a growing area of academic and industrial interest due to its promise for enabling time-sensitive use-cases and reducing operating costs. Likewise, the evolution, performance, and adoption of the Data Distribution Service (DDS) standard has made it a candidate for the connectivity fabric between Mobility Services. We study the synthesis of the two technologies through the development of an Edge-based Mobility Services (EMS) architecture over DDS. We evaluate this through a safety-critical case-study, Beyond-Line-of-Sight (BLoS) pedestrian tracking. Our approach is systems oriented, focusing on architecture, implementation, and demonstration using a realistic hardware-software testbed which provides convincing evidence for the synergy between the technologies