Epistemix draws on expertise in epidemiology, clinical practice, and computer science to understand and represent how epidemics spread in populations using the FRED agent-based modeling platform. We use FRED (Framework for Reconstructing Epidemiological Dynamics) to create and analyze epidemiological models and simulate how populations change over time. FRED was developed over 10 years with funding support from the NIH and the Bill & Melinda Gates Foundation. FRED modeling has led to dozens of scientific publications, enabled California State Senator Richard Pan to introduce and pass legislation to tighten state vaccine exemption laws, has been used to model social determinants of health, and currently is been used by states and health systems to forecast the spread of the COVID-19 epidemic. Our software platform represents every individual in the US population as a unique computational agent, each with their own unique geography, demographics, social contacts, and environmental interactions. This enables models to be dynamic and to include individual responses and behaviors as they would actually happen in space and time specific to any geography across the US. This is an important factor when considering the COVID-19 re-opening policy needs to be done through local government. Once a model is built on our platform, any number of interventions or strategies can be played out to develop and evaluate polices to achieve outcomes important to the modeler and decision maker.