https://bugzilla.redhat.com/show_bug.cgi?id=1115702
--- Comment #3 from Tom Hughes tom@compton.nu --- Well the point is that the gulpfile runs es6-transpiler on the source to create the js that goes in the npm tar ball - the build:lib task.
Other than that, this has a dependency on js-base64 which doesn't seem to be packaged yet.