Open source development (OSD) of software is becoming increasingly desirable for individuals and organizations alike. Organizations that heavily resisted this new way of developing software are now actively participating in this process. Participation of developers in the OSD environment has been a focal point of research in the information systems (IS) domain that has examined various reasons developers participate in project development. Our study goes beyond participation and looks at engagement of developers in the OSD environment. Using the job characteristics model (JCM), we conduct a comparative analysis of how job characteristics influence engagement of IS developers in open source and proprietary environment. Job characteristics have been found to play a very important role in driving individual work outcomes such as engagement and job satisfaction. Our study is expected to enrich the open source literature, extend JCM. The study will also provide new insight to organizations that are currently investing in OSD or planning to do so in the near future.