PhoSim-NIRCam is a full end-to-end JWST/NIRCam image simulator built on the framework of the LSST image simulator PhoSim. It contains a comprehensive physical model of the JWST telescope + NIRCam, and simulates photons propagating through the whole system using a Monte Carlo approach. PhoSim-NIRCam is easy to use, allowing the user to start creating realistic NIRCam images with minimal preparation. It also provides a variety of advanced features that allow direct control of any element in the system.
Although developed primarily for LSST, PhoSim itself is a physics-based code that can simulatie any optical/IR observing system when used with appropriately constructed configuration files. PhoSim-NIRCam has been developed by taking advantage of this feature, and is essentially PhoSim that comes with a particular set of configuration files constructed for JWST + NIRCam. Despite its complex inner working, PhoSim-NIRCam is easy to use, and is typically run as a one-line command with a CatalogFile and a CommandsFile.
Disclaimer: PhoSim-NIRCam is still in the early phase of develpment, and has not been tested extensively!
LSST PhoSim
JWST PhoSim-NIRCam