Swift Goes Open Source (Finally) - Foundation Framework too!
In case you missed it - the Swift programming language is finally Open Source!
Today we launched the open source Swift project along with the Swift.org website. We couldn’t be more excited to work together in an open community to find and fix issues, add enhancements, and bring Swift to new platforms.

But also hidden in there is the news that the Foundation Framework was open sourced but with a little interesting side note -
substantial reimplementation of the same APIGitHub project page
Completely independent of the Objective-C runtime. MIND BLOWN.
More: https://swift.org/blog/