Karl Fogel is the author of producing-open-source-software-2005, the most comprehensive practical guide to running a FOSS project — covering governance, community management, communication norms, licensing decisions, and the social dynamics of volunteer collaboration.
Fogel developed his understanding from direct experience as a developer on GNU Emacs and, especially, as a principal developer of Subversion, the version control system that preceded Git as the dominant FOSS collaboration tool. Subversion itself emerged from the Apache Software Foundation environment, and Fogel's account of how that community operated informed the book.
The first edition of producing-open-source-software-2005 was published by O'Reilly in 2005 and made freely available online under a Creative Commons license — an early and successful example of applying FOSS principles to technical writing. The second edition (2017) updated the text for the github-platform era, reflecting changes in code-review-in-foss, contributor-license-agreements, and mentorship-programs-gsoc.
Where eric-raymond's cathedral-and-the-bazaar-1997 made the theoretical and rhetorical case for open source, Fogel's work addressed the operational questions that actually confront project maintainers: how to handle toxic contributors, when to fork, how to write a good commit message, how to manage release cycles, how to structure governance when volunteers have no obligation to stay. This practical orientation positioned the book as a complement to the movement's ideological literature rather than a contribution to it.
Fogel has also contributed to thinking about maintainer-sustainability-crisis and the governance challenges of large FOSS projects in the modern-foss-and-sustainability-crisis-2015-present era.