Apple first unveiled Swift for writing Mac and iOS apps at its WWDC 2014 developer conference. The language works in Apple’s Xcode integrated development environment (IDE) and its Cocoa and Cocoa Touch frameworks.
In June, Apple first announced plans to open source the Swift compiler and libraries for iOS, OS X, and Linux. At the time, the company said it would make the big step by the end of the year, and so it has delivered in the last month of 2015.
On the Swift website, Apple laid out the news:
We are excited by this new chapter in the story of Swift. After Apple unveiled the Swift programming language, it quickly became one of the fastest growing languages in history. Swift makes it easy to write software that is incredibly fast and safe by design. Now that Swift is open source, you can help make the best general purpose programming language available everywhere.
For students, learning Swift has been a great introduction to modern programming concepts and best practices. And because it is now open, their Swift skills will be able to be applied to an even broader range of platforms, from mobile devices to the desktop to the cloud.
Welcome to the Swift community. Together we are working to build a better programming language for everyone.
With its support for object-oriented programming and whole module optimization, Apple has previously described Swift as “a successor” to C and Objective-C. The company reiterated that today by describing Swift as “a replacement for C-based languages (C, C++, and Objective-C).”
In addition to technical documentation and direct links to source code, the Swift website also features a blog where you can expect Apple will announce future plans for the programming language.