CyPhySim: a cyber-physical systems simulator. This demo provides a preview of a pre-release version of CyPhySim, an open-source simulator for cyber-physical systems. This simulator supports discrete-event models, quantized-state simulation of continuous dynamics, the Functional Mockup Interface (FMI), classical (Runge-Kutta) simulation of continuous dynamics, modal models (hybrid systems), discrete-time (periodic) systems, and algebraic loop solvers. CyPhySim provides a graphical editor, an XML file syntax for models, and an open API for programmatic construction of models.