Hi! You can submit .playground files that work with Xcode 11.4.1, or .playgroundbook files that work with Swift Playgrounds 3.3 on iPad or Mac. One of the questions on the application form asks which software should be used to run your playground, and you can make your selection there. Please note that the Xcode Author Template is a tool designed for authors (usually educators) producing .playgroundbook files, as it enables hiding code and setting custom reset points. While it does result in a playground, this template doesn’t fully align with the purpose of the Challenge. It intentionally supports Xcode 11.1 because the Swift compiler needs to match the version within the Swift Playgrounds app for Mac or iPad.