With the Xcode 8 GM release, plugins are no longer supported, and therefore our Xcode plugin no longer works. Xcode has never officially supported third party plugins and no public APIs are available. However, over 500 plugins, including the OneSky Xcode plugin, were created using private APIs and code injection bundles.
One workaround to this recent change would be to un-sign your Xcode copy, which is not the most ideal solution.
Another option would be to turn the plugin into a standalone app. OneSky product team will contemplate this option for our Xcode plugin.
Please reach out to our support team if you have any questions or concerns.