Free as in Freedom: Richard Stallman's Crusade for Free Software

Williams wrote this biography of Richard Stallman with Stallman's cooperation but without his editorial control, and the result is both sympathetic and clear-eyed. The book traces Stallman's path from the MIT AI Lab's culture of shared code through the founding of the GNU Project and the Free Software Foundation to the creation of the GPL — the license that turned a personal ethic into an institutional mechanism. Williams is especially good on the tension between Stallman's absolutism and the pragmatic needs of a movement that wanted to win adoption. The book was published under the GNU Free Documentation License and is freely available on gnu.org, making it a primary document as well as a secondary one. For product people, understanding Stallman is understanding the ideological bedrock beneath every open-source dependency in your stack. You do not have to agree with him to recognize that his choices shaped the infrastructure you build on.