Engineering students need to improve their business competence. One of the most effective methods are decision-making games in the area of business. The article presents the technology for building mathematical models of situations simulated in games of decision-making and an authoring system of developing and implementing serious simulation games using web technologies. The developed software system allows to create a game by defining and testing the computing model of the simulated situation, the user interface, the game's implementation, and an analysis of its results. An example of game developed with the aid of the system and used for training engineering students is also presented. It takes into account the specificity and level of the business knowledge of engineering students.