Following its open source release, Swift can be downloaded at http://www.swift.org. I am lucky enough to see that there is Linux version available for download. The binary version was developed in Ubuntu, so I tried to grab the binary release and then have them installed to no luck. It was some problems with some libraries: libpanel (from ncurses5), libedit.so.2 and libicuuc. Being a bleeding edge...
Swift in Arch Linux