Although material components of digital infrastructure stacks are often understood as operating through platforms or protocols in a smoothly interconnected way, their expansion, repair, and continued functionality nevertheless require significant interventions in the material world. These include the installation, repair, and maintenance of fiber-optic backbones, as well as the disruption of everyday residential life for the purpose of “last mile” fiber installations. Based on participant observation conducted with construction teams engaged in rebuilding the base level of Shanghai’s digital infrastructure stack, this article questions “plug-and-play” views of Chinese digital infrastructure, instead refocusing analysis on the legal and sociocultural technologies that facilitate material infrastructural construction. In the case of Shanghai’s Overhead-Underground project, legal and social mechanisms that facilitate migration have themselves become crucial to the physical aspects of digital infrastructure, which is built through subcontracted low-waged labor systems that rely on assumedly temporary rural-to-urban migrant labor. The resulting systems of labor provision both reflect and maintain the structure of a politically divided public: High-quality “smart city” infrastructure is built for the service of an avowedly urban public, but only through a reliance on “low-skilled” rural migrant construction workers, who are formally and informally excluded from the city their infrastructural interventions are designed to serve.