Machine control is a demanding application area for embedded computer systems. Modern machines used in applications in for example manufacturing, farming, forestry and transportation sectors are modular and their control is computerized. The need for customer-specific product variations is becoming increasingly common. Safety and reliability requirements must be strictly satisfied, although product development time and costs should be minimized. A computerized system for the assembly of reusable software components as a practical means for rapid configuration and just-in-time delivery of machine control systems is discussed.