100 days: the current target for a safe and effective vaccine against a new pandemic threat. Three times faster than the dizzying pace of biomedical development for COVID-19, this R&D moonshot is ambitious, but with new plug-and-play vaccine platforms, public-private collaborations, tech-transfer hubs, compressed regulatory pathways and readymade experimental protocols, a goal potentially within reach. This biomedical accelerationism promises more than a pandemic-free future: it offers a radical reimagining of global health. Rather than defining its goal as expanded access to life-saving products, this initiative would engineer equity into the material practices of manufacture: a model of just-in-time innovation that is also fundamentally more just. Drawing together ethnographic insights from diverse range of infectious disease interventions, I weigh that promise. By attending to highly situated processes of product design, manufacturing, regulation, and supply, I make the case for a “tropicalized” version of pragmatism—a critical turn that recognizes and rises above imperial legacies and humanitarian conventions.