I found crash reports related to this: Process: XCBBuildService [88276] Path: /Applications/Xcode-beta.app/Contents/SharedFrameworks/XCBuild.framework/Versions/A/PlugIns/XCBBuildService.bundle/Contents/MacOS/XCBBuildService Identifier: XCBBuildService Version: 13.1 (19453) Build Info: XCBuild-19453000000000000~7 (13A1030d) Code Type: X86-64 (Native) Parent Process: Xcode [88227] Responsible: Xcode [88227] User ID: 501 Date/Time: 2021-10-25 09:29:58.569 +0200 OS Version: macOS 11.6 (20G165) Report Version: 12 Bridge OS Version: 5.5 (18P4759a) Anonymous UUID: A0496C37-F5FE-6AF6-FD23-F367C8D3C235 Sleep/Wake UUID: A2A0FF9D-01E8-4BF6-A887-5F3820ACA4ED Time Awake Since Boot: 230000 seconds Time Since Wake: 200000 seconds System Integrity Protection: enabled Crashed Thread: 8 Dispatch queue: XCBBuildService.ActiveBuild.operationDelegateQueue Exception Type: EXC_BAD_INSTRUCTION (SIGILL) Exception Codes: 0x0000000000000001, 0x0000000000000000 Exception Note: EXC_CORPSE_NOTIFY Termination Signal: Illegal instruction: 4 Termination Reason: Namespace SIGNAL, Code 0x4 Terminating Process: exc handler [88276] Application Specific Information: XCBCore/Settings.swift:315: Fatal error: Couldn't load file type spec file.rcproject in domain macosx Thread 0:: Dispatch queue: XCBBuildService.ServiceHostConnection.receiveQueue 0 libsystem_kernel.dylib 0x00007fff204c8cce read + 10 1 com.apple.dt.XCBServiceCore 0x000000010ffa95b8 closure #1 in ServiceHostConnection.resume() + 104 2 com.apple.dt.XCBServiceCore 0x000000010ffaa9ce thunk for @escaping @callee_guaranteed () -> () + 14 3 libdispatch.dylib 0x00007fff20352623 _dispatch_call_block_and_release + 12 4 libdispatch.dylib 0x00007fff20353806 _dispatch_client_callout + 8 5 libdispatch.dylib 0x00007fff203595ea _dispatch_lane_serial_drain + 606 6 libdispatch.dylib 0x00007fff2035a0ad _dispatch_lane_invoke + 366 7 libdispatch.dylib 0x00007fff20363c0d _dispatch_workloop_worker_thread + 811 8 libsystem_pthread.dylib 0x00007fff204fa45d _pthread_wqthread + 314 9 libsystem_pthread.dylib 0x00007fff204f942f start_wqthread + 15

I unzipped the Xcode again today and now it works. Seems like the last version was not uncompressed correctly. And comparing both shows a size difference: 34676192 vs 34759632. It would really be better to distribute Xcode with a dmg instead of a zip archive.

The version is 13.1 (13A1030d) on Big Sur 11.6. I just made a new project. Console app with Objective-C. It still fails, so it's not my project: Showing All Messages Prepare build note: Using new build system note: Planning unexpected service error: The Xcode build system has crashed. Build again to continue.error: unexpected service error: The Xcode build system has crashed. Build again to continue. Build failed 26.10.21, 09:55 0.5 seconds I also cleared all temp folders. XCBBuildService crashes with failed assertion: XCBCore/Settings.swift:315: Fatal error: Couldn't load file type spec file.rcproject in domain macosx What could this be?

Same here for at least an hour :-(