Cummins Inc. (4th Case)

Company Background

Cummins Inc. is a global leader in developing, distributing, and servicing engines and related technologies, including fuel systems, controls, air handling, filtration, emission solutions, and electrical power generation systems.


Software is becoming ever more important for controlling the operation of an engine, e.g. electronics control the ignition and the fuel delivery. The software must be robust and highly reliable. In late 1993 six critical engine software projects were underway, with another twelve planned.


Every developer team worked autonomously and with different standards; for example, there was no common programming language and no reference architecture defined. Being anxious about the quality of the resulting applications, the project leader stopped all projects and established a focus group to develop core assets that all the applications could use. Furthermore, he defined common software development processes. The first software product line at Cummins Inc. was therefore born.


The experience of Cummins Inc. with the software product line approach is consistently positive. Cummins Inc. is able to build over 1000 different products based on the software product line. A wide variety of different functionality is integrated into the software product line: nine basic engine types ranging over 4-18 cylinders and 4-164 litres of displacement, with 12 kinds of electronic control modules, 5 kinds of processors, and 10 kinds of fuel systems. Cummins estimated that it would take more than 360 software engineers to produce these software systems separately instead of the 100 software engineers actually needed due to the software product line approach. This is an estimated productivity improvement of 3.6. Cummins also estimated an ROI (Return On Investment) of 10:1. Furthermore, Cummins can quickly access new markets, from rock crushers to ski lifts.


  • P. Clements and L. Northrop; Software Product Lines - Practices and Patterns, Addison-Wesley, 2001, pp. 417-442.
  • J.C. Dager; "Cummins's Experience in Developing a Software Product Line Architecture for Real-time Embedded Diesel Engine Controls", In: Proceedings of the First Software Product Lines Conference (SPLC-1), Denver, Kluwer, 2000, pp. 23-46.
  • SPLC2 - Product Line Hall of Fame (Website)