Early in the Covid-19 pandemic, challenges emerged that pointed to the need for connecting diagnostic, clinical, and demographic data at scale to support real-time monitoring and decision-making by public health agencies. Driven by this urgent need, a number of public and private entities worked to deploy data programs across the United States to address the information fragmentation and to improve the public health response to Covid-19. Connected systems that continue to incorporate dynamic information are vital to pandemic response efforts, both today and in future public health efforts. In this article, leaders from Verily Life Sciences share their experiences in building a Covid-19 Research platform (C19R) to support a cross-country program for Covid-19 testing that demonstrates the potential for linking community-based diagnostic, clinical, demographic, and other data to support public health decision-making at scale. The program also creates the infrastructure for a learning system where public health actions can be informed by aggregated clinical care data, evolving insights, and ongoing evidence generation, thereby linking research and care delivery.