This paper describes a project that attempts to develop a holistic solution for integrating a simulated twin of an automation system during the system’s entire life-cycle. With such holistic solution, virtual commission could be undertaken in all steps of the life-cycle which facilitates companies in realizing flexible and intelligent automation systems. Based on the simulated twin, the companies could easily and cost-efficiently evaluate modifications, make improvements, and train operators when changes in the production setup occurs due mass-customization or new products being introduced. This aids the companies in staying competitive on a global and rapidly changing market and meet the challenges coming with the forth industrial revolution, such as mass-customization and short product life-cycles.