Campus networks - with his high diversity of users, traffic requirements, fast changing roles, and openness of equipment (BYOD) - present multiple unique challenges difficult to meet with traditional networking technologies. SDN/OpenFlow provides a new toolset to rethink and redesign a campus network with aims at higher scalability, flexibility, and lower cost. This paper presents PUCPLight, an SDN/OpenFlow controller for a layer 2 campus network of tens of thousands of users. PUCPLight is a first approximation to a vision of a pure SDN scalable, flexible campus network that seamlessly supports from administrative services, to high performance computing, to experimental research. This paper describes the drives behind PUCPLight design, some of the design choices, as well as initial results proving scalability to a subnet of 10K nodes.