Introducing the IBM Swift Sandbox - Swift
developer.ibm.com/swift/2015/12/03/introducing-the-ibm-swift-sandbox
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
The IBM Swift Sandbox is an interactive website that lets you write Swift code and execute it in a server environment – on top of Linux! Each sandbox runs on IBM Cloud in a Docker container. In addition, both the latest versions of Swift and its standard library are available for you to use.