Physics-based forecasts of seismic hazard from future earthquakes are important for developing plans for land use, building codes, transportation and communication infrastructure, power and water systems, and many other aspects that are integral to society. The Quakeworx framework is a new multi-disciplinary collaboration to enable a wide community of users to access state-of-the-art physics-based models of rupture forecasts, further improve existing tools, and validate model results. Quakeworx also helps advance the science of rupture forecasts, obtain new insights on earthquake physics, improve seismic hazard estimates, and create new opportunities for STEM education and engagement. Quakeworx enables rapid immersion of students, post-docs, and early career scientists with state-of-the-art simulation and analysis tools that aid in modernizing education and training in earthquake physics, computational modeling, software engineering, and related fields. The project contributes to the national interest by supporting a more resilient society with improved capabilities for forecasting earthquakes and assessing seismic hazard, which are foundational for mitigation of seismic risk, contributing to STEM workforce development, and facilitating translation of results to the society at large.<br/><br/>A core element of Quakeworx is a new science gateway, which provides access to state-of-the-art methods that combine novel physics-based modeling frameworks with standardized pipelines for simulations, data-based assimilation to inform and validate models on-demand, and machine-learning pattern recognition on big datasets. The project enables simulations of coupled evolution of earthquakes and faults producing diverse outputs (seismicity, ground motion, fault network configuration, strain rates, topography), and facilitates the development, validation, application, and reproducibility of improved rupture forecasts for research and education. Quakeworx curates and seeds many leading tools and data products that leverage existing community data models describing fault and rock properties as simulation input. Additionally, the gateway enables the research and education community to contribute, curate and share tools for simulations, data analysis and visualization, data products and knowledge base. The project provides a foundation that eliminates barriers due to lack of expertise and lack of access to compute resources, and it delivers an innovative service-oriented and easy-to-use cyberinfrastructure to a large user community.<br/><br/>This award by the NSF Office of Advanced Cyberinfrastructure is jointly supported by the Division of Research, Innovation, Synergies, and Education (RISE), the Division of Earth Sciences (EAR), and the Geophysics Program within the NSF Directorate for Geosciences.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.