Nominal Editor is a high-fidelity digital twin sandbox designed for engineers who need comprehensive customization, integration, and collaborative control over space mission simulations. Built for flexibility and scalability, the Editor enables users to model real-world systems in detail,integrate external software and simulation tools, and build custom applications tailored to mission needs. With an open-source component library and robust collaborative features, teams can work together seamlessly, share real-time insights, and develop bespoke capabilities to address unique challenges in mission-critical operations.