Do Open Source Developers Respond to Competition? The Case Study

This paper traces the history of TeX, the open source typesetting program. TeX was an early and very successful open source project that imposed its standards in a particularly competitive environment and inspired many advances in the typesetting industry. Developed over three decades, TeX came into competition with a variety of open source and proprietary alternatives. I argue from this case study that open source developers derive direct and indirect network externalities from the use of their software by others and must therefore consider non-developers' needs to make their software more attractive to a broader audience and more competitive with proprietary alternatives.