The current generation of ABB robot controllers contains an embedded software, RobotWare, that saw first light already in 1994 with the S4 robot controller. Since then RobotWare has been continuously developed, refactored and refurbished to comply with the demands of the modern factory floors of today as well as the collaborative robot applications (Cobot) and flexible production facilities of the future. In the presentation the modular and agile approach to achieve this will be presented as well as the challenges that have been addressed and are foreseen.