It looks like Apple may have consolidated the swift data macros into libSwiftMacros.dylib. I was able to fix as follows Go to build settings of the app Search for "Other Swift Flags" Double click to open it up Change ${TOOLCHAIN_DIR}/usr/lib/swift/host/plugins/libSwiftDataMacros.dylib to ${TOOLCHAIN_DIR}/usr/lib/swift/host/plugins/libSwiftMacros.dylib