  The recently proposed generalized epidemic modeling framework (GEMF)
\cite{sahneh2013generalized} lays the groundwork for systematically
constructing a broad spectrum of stochastic spreading processes over complex
networks. This article builds an algorithm for exact, continuous-time numerical
simulation of GEMF-based processes. Moreover the implementation of this
algorithm, GEMFsim, is available in popular scientific programming platforms
such as MATLAB, R, Python, and C; GEMFsim facilitates simulating stochastic
spreading models that fit in GEMF framework. Using these simulations one can
examine the accuracy of mean-field-type approximations that are commonly used
for analytical study of spreading processes on complex networks.
