CropSyst is a simulation model jointly supported and developed by Claudio Stöckle (Project Leader), Roger Nelson, and Armen Kemanian.

Like Cycles, CropSyst is a multi-year cropping system model. CropSyst has been developed to support large applications, with structured databases to handle batch run simulations and efficient data flow for fast simulations in desktop or HPC. The learning curve with CropSyst is steeper than that for Cycles, but appropriate for large projects. Users can start with Cycles, which offers simplicity and an excellent blueprint to handle CropSyst later. The code in Cycles is more amenable for coupling with other models and to work with students.

Cropsyst is freely available at Washington State University.