Swift, along with the other top 10 skills that made the list in the fourth quarter of 2016, experienced more than 200 percent year-over-year growth. Other skills that have become more essential on Upwork alongside Swift include natural language processing, Tableau, Amazon Marketplace Web Services, and Stripe.
Introduced in 2014, Swift is Apple's programming language, developed in part by Chris Lattner who made headlines recently when he left Apple for Tesla. Designed to be concise yet expressive, Swift replaces Objective-C and is being increasingly adopted by developers.
Swift is meant to be simple to learn, something Apple highlights with Swift Playgrounds, an app that teaches children to code using the Swift language. Apple has been updating and refining Swift since its 2014 debut, and is set to unveil Swift 3.1 in the spring of 2017.
Upwork's Skills Index measures year-over-year growth rates based on freelancer billings through the Upwork site.