Stochastic Process Simulation Engine R package StochSimR version 1.1.0 A modular simulation engine for a wide range of stochastic processes. Provides exact and approximate simulation methods for Poisson processes (homogeneous and inhomogeneous), Brownian motion (standard, drifted, and bridge), discrete- and continuous-time Markov chains, birth-death processes, the Yule pure-birth process, infinitesimal generator matrix utilities, Markovian queuing systems (M/M/1, M/M/c, M/M/c/K) with exact steady-state statistics, Levy processes (gamma, normal inverse Gaussian, variance-gamma, alpha-stable), Merton jump-diffusion models, Hawkes self-exciting processes, geometric Brownian motion, and Ornstein-Uhlenbeck mean-reverting diffusions. Includes variance reduction techniques (antithetic variates, control variates, importance sampling, stratified sampling), parallel simulation via the 'future' framework, rare-event simulation (cross-entropy and multilevel splitting), path visualisation, and summary statistics. Methods are based on Glasserman (2003) <doi:10.1007/978-0-387-21617-1>, Asmussen & Glynn (2007) <doi:10.1007/978-0-387-69033-9>, Norris (1997) <doi:10.1017/CBO9780511810633>, and Kleinrock (1975, ISBN:0471491101). Software Depends: R (>= 3.5.0) Imports: ggplot2 (>= 3.4.0), rlang (>= 1.0.0), stats, parallel, future (>= 1.25.0), future.apply (>= 1.10.0) Suggests: testthat (>= 3.0.0), knitr, rmarkdown Ayush Kundu <ayushkundu25@iitk.ac.in> Comprehensive R Archive Network (CRAN) Ayush Kundu [aut, cre] (ORCID: <https://orcid.org/0009-0009-8715-2624>) MIT + file LICENSE (https://CRAN.R-project.org/package=StochSimR/LICENSE) 2026-06-01 application/tgz https://CRAN.R-project.org/package=StochSimR doi:10.32614/CRAN.package.StochSimR