Evolution of the OpenQuake Engine: Enhanced capabilities, collaborative development, and global adoption

The OpenQuake Engine started being developed in 2010 and was publicly introduced in 2014 as an open-source software for seismic hazard and risk modeling, aiming to provide a transparent, flexible, and globally accessible platform to the earthquake engineering and hazard science communities. Over the subsequent decade, extensive advancements have significantly expanded its capabilities and enhanced its adoption worldwide. This article comprehensively reviews these developments, detailing the new computational workflows and features implemented in the OpenQuake Engine with an emphasis on the risk component, improvements in its computational efficiency and scalability, and its growing global application across diverse geographical and thematic contexts. Major improvements to the OpenQuake Engine include the earthquake-triggered landslide and liquefaction modules, the infrastructure risk and network connectivity analysis module, the post-event loss amplification module, the financial loss module for insured and reinsured loss calculations, the classical and event-based probabilistic damage calculators, and the site-amplification module. Additional features include the option to condition ground motion fields on station data in scenario calculations, ability to connect ShakeMap outputs to the OpenQuake Engine’s damage and loss calculators, the conditional spectra calculator, vector-valued PSHA, and extension of the risk calculators to volcanic hazards. Performance improvements and enhancements in documentation have been pivotal in strengthening the software’s usability across a variety of computational platforms and user groups. A core contribution of this article lies in compiling and synthesizing over a hundred studies conducted using the OpenQuake Engine, thereby illustrating its versatile application at national, regional, urban, and site-specific scales. Moreover, examples of its use in earthquake insurance pricing and parametric catastrophe bond design are highlighted, demonstrating its practical relevance to risk management and financial resilience. Reflections on lessons learned regarding the importance of open-source practices, robust documentation, sustained user engagement, and interdisciplinary collaboration are discussed to inform future development and maintenance of scientific software with global applications.