Deploying stream computing applications on edge networks brings a new set of challenges including frequent reconfigurations due to client mobility and topology changes, geographical constraints from application semantics, state management over wide-area networks, and more. Current stream processing frameworks do not adequately address these challenges since they are designed for use inside data centers and rely on global coordination between participating nodes. Merlin is a new stream processing framework designed from the ground up for stream processing on the edge. Merlin supports fast reconfiguration without disrupting applications by decoupling data delivery from data processing and removing the need for global coordination.