SmallDEVS is a new implementation of B. Zeigler's DEVS formalism. Its design is based on Zeigler's book "Theory of Modeling and Simulation" and partially influenced by Python DEVS (http://moncs.cs.mcgill.ca/MSDL/research/projects/DEVS/). It is an experimental software. It allows for experimenting with prototype-based model construction, interactive modeling and simulation, multisimulations and reflective simulation. References: