Generic Engine for Module Software Task Orchestration and Negotiation (GEMSTONe): A Multi-Stage Workflow System for Orchestrating Virtual Imaging Trials.

Virtual imaging trials rely on complex, multi-stage computational workflows spanning a large array of software systems for patient modeling, image simulation, and analysis. Integrating heterogeneous software modules into efficient, reproducible, and scalable workflows remains challenging: ad hoc conventions, manual handoffs between developers, and inconsistent file formats often lead to fragile, error-prone results. To address these challenges, we developed GEMSTONe, a Generic Engine for Modular Software Task Orchestration and Negotiation, which decouples domain-specific module computation from a centralized workflow manager through declarative configuration, automated parameter validation, standardized module interfaces, and centralized path management. We deployed three GEMSTONe example workflows: a refactor of a recently studied virtual imaging trial (i.e., Virtual Lung Screening Trial), a high-throughput CT simulation scheduler, and an interoperable workflow integrating two breast imaging pipelines (FDA VICTRE and the University of Pennsylvania OpenVCT). Key findings included a 3.5 × speedup through engine-level mechanisms alone and the feasibility of refactoring, integrating, validating, and combining VICTRE and OpenVCT in less than five weeks. The generic nature of GEMSTONe makes it applicable beyond medical imaging, establishing it as a general framework for complex, multi-stage computational workflows.