Overview of the MCU Monte Carlo software package

•MCU is the Monte Carlo code for particle transport in 3D systems with depletion.•Criticality and fixed source problems are solved using pure point-wise approximation.•MCU is parallelized with MPI in three different modes.•MCU has coolant, fuel and xenon feedback for VVER calculations.•MCU is verified for reactors with thermal, intermediate and fast neutron spectrum. MCU (Monte Carlo Universal) is a project on development and practical use of a universal computer code for simulation of particle transport (neutrons, photons, electrons, positrons) in three-dimensional systems by means of the Monte Carlo method. This paper provides the information on the current state of the project. The developed libraries of constants are briefly described, and the potentialities of the MCU-5 package modules and the executable codes compiled from them are characterized. Examples of important problems of reactor physics solved with the code are presented.