The number of networked “smart devices” available in everyday environments is rapidly increasing; however, most adopt mutually incompatible networks, protocols, and application programming interfaces. In previous work, we introduced a variety of adaptive middleware techniques that enables a user’s commodity mobile device (e.g., a smartphone) to serve as an adaptive gateway between mutually incompatible devices –- providing service adaptation and protocol translation services through plug-ins that can be installed on-the-fly. In this paper, we present a complementary set of novel smart space design tools, which enable non-programmers to visually “remix” their ambient environments in new, playful and potentially unforeseen ways using an intuitive flow-graph model. Visual designs can be sent over the network to the user’s mobile device, which instantiates them during runtime. This paper presents a detailed overview of the approach, introduces our fully functional prototype, and presents a user study that provides encouraging first results.