Tried that, but it seems the build setting now needs an explicit SWIFT_VERSION configured .. And carthage dependencies don't have that so the build fails.

Basically, I couldn't get my carthage dependencies to compile with Swift 2.3, so I went the Swift3 route, which now, after 10 hours wasted, was such a bad idea!

Appstore was bugging me to update Xcode so I caved in and now I'm stuck with a project that doesn't build and the deadline approaching fast. Such a useless waste of time.