Open Software in a Commercial Operating System A paper written by Wilfredo Sánchez, the then Open Source Engineering Lead at Apple, about the use of open source in commercial software such as Mac OS X Server. http://www.mit.edu/people/wsanchez/papers/FREENIX99.html
The Challenges of Integrating the Unix and Mac OS Environments A paper on the design issues Apple faced when they ported the Mac OS to a semantically different Unix base (Darwin). http://www.mit.edu/people/wsanchez/papers/USENIX_2000/
The GNU-Darwin Distribution A Unix distribution which focuses on the porting of free software to Darwin and Mac OS X. http://www.gnu-darwin.org/
XDarwin: X Windows on Darwin and Mac OS X A general overview of the project to bring XFree86 (X11 server) to Darwin and Mac OS X as well as pointers to download and mirror sites. http://www.xdarwin.org/
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