Installing via the .xip file allows you to keep multiple versions of Xcode on your system, which is useful if you are migrating a project.
: Double-click the Xcode_9.4.1.xip file. The Archive Utility will verify the digital signature and begin extraction. xcode 9.4.1.xip download
While newer versions like Xcode 15 or 16 are standard for modern development, Xcode 9.4.1 is necessary for: Installing via the
iOS 11.4, watchOS 4.3, tvOS 11.4, and macOS High Sierra 10.13 How to Install Xcode from a .xip File xcode 9.4.1.xip download