The fourth industrial revolution introduces changes in traditional manufacturing systems and creates basis for a lot-size-one production. The complexity of production processes is significantly increased, alongside the need to enable efficient process simulation, execution, monitoring, real-time decision making and control. The main goal of our research is to define a methodological approach and a software solution in which the Model-Driven Software Development (MDSD) principles and Domain-Specific Modeling Languages (DSMLs) are used to create a framework for the formal description and automatic execution of production processes. In that way production process models are used as central artefacts to manage the production. In this paper, we propose a DSML which can be used to create production process models that are suitable for automatic generation of executable code. The generated code is used for automatic execution of production processes within a simulation or a shop floor.