France has a decades-long history of devastating heat mortality, with high fatality counts in metropolitan areas like Paris, Lyon, and Strasbourg. These deaths largely occur at social and spatial fault lines, placing vulnerable and isolated people at immense risk during heat events. Marseille, France’s second largest and most outwardly disadvantaged city, continues to buck this trend with comparatively low heat mortality despite its demographic ordinariness, history of social and built environment issues, and lackluster heat policies and planning initiatives. This thesis explores this difference through an urban sociological lens: how do Marseille residents build community-level resilience in the absence of political support? Building on literature review, site visit data, and semi-structured interviews, I argue that Marseille residents act as heat wave infrastructure out of necessity, fostering precarious but, currently, effective community heat resilience.