The chapter examines the emergence of the smart microgrid as a logic of grid security that can seamlessly switch between ‘normal’ and ‘emergency’ configurations in microseconds. It contributes to further understanding of the evolving temporalities of urban infrastructure configurations in three ways. We first locate the ‘always-on’ uninterruptible capacity of the smart microgrid in a series of concepts, ideas and strategies developed in work on self-healing systems in a variety of contexts. We then trace the development of the smart microgrid in US military and urban contexts, exploring how it has become central to a logic of urban resilience that seeks to mitigate threats and prepare for future turbulence by pursuing the reconfiguration of grids into permanent ‘alert’ mode. Finally, we outline the differential, asynchronous experience of seamless transition enabled by smart microgrids whereby new forms of socio-spatial selectivity are produced through infrastructure temporalities.