2017 is a good year for the open source community. For the first time in the history of computer and software development, we've seen major corporations join in supporting the open source movement. Google, Facebook, Microsoft are just a few names.
Apple just open sourced its iOS and macOS Kernel for ARM processors. The XNU kernel is a part of the Darwin operating system that powers Apple’s iOS and macOS operating systems.
Darwin is built on the Unix BSD OS and was open sourced in 2000. Apple’s operating systems, iOS, watchOS, macOS, and tvOS are based on Darwin.