Apple team has released the source code for Darwin 7.0, updating it for Mac OS X 10.3 (“Panther”).
Darwin, the core operating system of Mac OS X, is one of Apple’s open source projects. Open source is a term for the historical development model used by the Internet community to facilitate distributed development of complex, high-quality software. Darwin is a version of the BSD UNIX operating system that offers advanced networking, services such as the Apache Web server, and support for both Mac and UNIX file systems.
In regards to Darwin 7.0, Apple says it “includes a large number of source projects.” The released version of each Darwin project is available to browse or download as a source archive.