Vapor toolbox is crashing when trying to use it after upgrading to Swift 3.1.
dyld: lazy symbol binding failed: Symbol not found: __TTSfq4n_s___TFVSS13CharacterView38_measureExtendedGraphemeClusterForwardfT4fromVVSS17UnicodeScalarView5Index_Si
Referenced from: /usr/local/bin/vapor
Expected in: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/libswiftCore.dylib
dyld: Symbol not found: __TTSfq4n_s___TFVSS13CharacterView38_measureExtendedGraphemeClusterForwardfT4fromVVSS17UnicodeScalarView5Index_Si
Referenced from: /usr/local/bin/vapor
Expected in: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/libswiftCore.dylib
Swift ABI is not yet stable. Thus, Swift programs (like Vapor Toolbox) must be recompiled to work with new versions of the language.
Reinstall with Brew
Simply re-installing the toolbox should fix this issue.
Replace Old Installation With Brew
You may need to delete the existing executable if you did not originally install with Homebrew
Then ensure the executable is gone
You can now install with brew
You can simply delete Vapor executable from
And then run the toolbox install script from the documentation