Why Do Developers Contribute to Open Source Projects? First Evidence of Economic Incentives

The availability of commercial quality, free software products such as the Apache HTTP (web) server or the Linux operating system has focused significant attention on the open source development process by which these products were created. One of the more perplexing aspects of open source software projects is why developers freely devote their time and energy to these projects. While many open source participants cite idealistic motives for participation, Lerner and Tirole (2000) argue that developer participation in open source projects may, in part, be explained by existing economic theory regarding career concerns. This research seeks to confirm or disconfirm the existence of economic returns to participation in open source development. Preliminary results of our empirical investigation suggest that greater open source participation per se, as measured in contributions made, does not lead to wage increases. However, a higher status in a merit-based ranking within the Apache Project does lead to significantly higher wages. This suggests that employers do not reward the gain in experience through open source participation as an increase in human capital. The results are also consistent with the notion that a high rank within the Apache Software Foundation is a credible signal of the productive capacity of a programmer.