Xcode 10 iOS 12 Multiple command

Xcode 10 iOS 12

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:-1: Multiple commands produce '/Users/me/Library/Developer/Xcode/DerivedData/myApp-bwuurptypnrscqweqwewwwlma/Build/Products/Debug-iphonesimulator/myApp.app':

Solution:
Xcode - File - Workspace Settings - Build System - select "Legacy Build System"