We will review the technical components of the NASA lunar rover mission, VIPER, with a focus on software components that rely on ROS 2 and Gazebo. We’ll start with an overview of the hardware and software components. Next, we’ll explore some of the custom Gazebo plugins for simulating the rover and the lunar surface. We’ll describe a fault injection framework that was built on ROS 2 parameters and how it is used to simulate hardware faults. Finally, we’ll see how ROS 2 is used as part of the rover ground software.