Ultra Electronics, ProLogic is developing the Reconfigurable Environment for Analysis and Test of Software Systems (REATSS) for NASA’s Independent Verification and Validation Facility located in Fairmont , WV. REATSS is a web-based composable simulation platform designed to provide an affordable life cycle cost that would enable dynamic testing on all phases of many of the facility’s projects. The simulation needs range in scope from low fidelity simulations that explore requirement issues to high fidelity simulations in which emulators execute operational code to enable non- destructive testing in a virtual environment. The REATSS platform will provide simulation capability by dragging multiple vehicle and mission control elements into a single environment and specifying their communication links. The program will also maximize available assets by utilizing dynamic rather than dedicated allocation of computer resources that may include participant’s desktops. Special provisions designed into the REATSS platform from the start provide specific support for analysis and test processes, including a fully versioned back-end storage system for all system elements and work products, and the integration of third party test development tools. Ultra Electronics, ProLogic is confident that the REATSS platform has great potential to be a strong player in the approaching transition to web-based simulation standards and the program has generated much interest. Our next step is to examine potential avenues for the application of REATSS technology to Department of Defense and Department of Homeland Security needs.