We shed light on understudied social infrastructure by focusing on the service hub, those conspicuous clusters of voluntary sector organizations designed to help the most vulnerable urban populations. Using Kamagasaki, Osaka as an exploratory case study, we find that the service hub acts as a distinctly inner-city social infrastructure marked by very close proximity of clients and services, as well as high accessibility, mutuality and provisionality, and clear motivations to ensure day-to-day survival. But the conversation between service hub and social infrastructure indicates that our case study must be understood as a bypassed infrastructure, unsung and out-of-sync with the market (but increasingly less so with the state). Kamagasaki suggested as social infrastructure of castoffs, standing apart and increasingly incompatible with current urbanism and its emphasis on privatization, gentrification and neoliberal co-optation, or even with the older 'infrastructural ideal' of the Fordist era, with its emphasis on large-scale universality.