I am using swift-subprocess, and need to disable the SubprocessSpan trait because Xcode 26.2 does not ship with a bundled version libswiftCompatibilitySpan.dylib, causing everything to crash built with Xcode that happens to use Span. However, I cannot disable that trait by doing any of the following things: .package( url: "https://github.com/swiftlang/swift-subprocess.git", branch: "main", traits: [] ), .package( url: "https://github.com/swiftlang/swift-subprocess.git", branch: "main", traits: [.trait(name: "SubprocessFoundation")] ), Note that SubprocessSpan is default trait in subprocess: // Enable SubprocessFoundation by default var defaultTraits: Set<String> = ["SubprocessFoundation"] #if compiler(>=6.2) // Enable SubprocessSpan when Span is available [except it is not] defaultTraits.insert("SubprocessSpan") #endif The package still builds with the SubprocessSpan enabled. This is not an issue with the subprocess package. According to this, I should use swift build on the command line, yet this isn't -- as is upgrading to Tahoe -- an option because I need Xcode previews for SwiftUI. Help, what do I do now (other than downloading a toolchain) from swift.org)?

Downloaded Xcode 26.2 from App Store. Started new Project, which defaults to "hello world". The canvas "simulator" within fails to finish indexing (paused), or When the canvas is active, the first code change (i.e. just a return key at the end of a line) cause the Xcode program to come to a stop. Have ended Xcode and rebooted a number of times. A number of remedies are posted on the net. All a little different than the other. Is there a current remedy for Xcode 26.2 to this issue available? iMac on Sequoia 15.7.3 , 800 gb of available storage Xcode: 26.2 (24553) Instruments: 26.2 (64573.16) SDKs: DriverKit: 25.2: iOS: 26.2: (23C53) iOS Simulator: 26.2: (23C53) macOS: 26.2: (25C57) tvOS: 26.2: (23K50) tvOS Simulator: 26.2: (23K50) visionOS: 26.2: (23N301) visionOS Simulator: 26.2: (23N301) watchOS: 26.2: (23S303) watchOS Simulator: 26.2: (23S303)

Hi, My certificates expired and I created new ones. But now Xcode shows me in Apple Accounts status of Mac App Distribution that the Missing Private... Howto fix the missing private key? I need to sign a .pkg for upload with Transporter. Further I generated a CSR for App License Delivery ALD certificates. https://developer.apple.com/help/account/certificates/create-a-certificate-signing-request/ And with App Store Connected I created new certificates. In Xcode I had to remove the Apple Account and add it again, after altering currency. This procedure was described somewhere because Xcode was not able to connect my account. This is fixed now.

Hello I am using 26.2 (25C56) on my m4 air. when I am working on a Flutter project suddenly my app crashed and after when I tried to build the application again this error occurs. How to fix it. ? Launching lib/main.dart on iPhone 16e in debug mode... Xcode build done. 2.4s Failed to build iOS app Uncategorized (Xcode): Unable to find a destination matching the provided destination specifier: { id:45967BD9-44E0-4D5D-8C43-C5437F48836A }Available destinations for the "Runner" scheme: { platform:macOS, arch:arm64, variant:Designed for [iPad,iPhone], id:00008132-001E5102020B801C, name:My Mac } { platform:iOS, id:dvtdevice-DVTiPhonePlaceholder-iphoneos:placeholder, name:Any iOS Device } { platform:iOS Simulator, id:dvtdevice-DVTiOSDeviceSimulatorPlaceholder-iphonesimulator:placeholder, name:Any iOS Simulator Device } Could not build the application for the simulator. Error launching application on iPhone 16e.

I am profiling a simple SwiftUI test app on my new iPhone through my new MacBook Pro and everything is version 26.2 (iOS, macOS, Xcode). I run Instruments with the SwiftUI template using all of the default settings and get absolutely zero data after interacting with the app for about 20 seconds. Using the Time Profiler template yields trace data. Trying the SwiftUI template again with the sample Landmarks app has the same issue as my app.

Hi everyone, I’m an iOS developer working on a Mac with limited storage (256 GB). I’ve noticed that the ~/Library/Developer folder is taking up almost 90 GB, mainly due to Xcode-related content. Inside it I see folders like: Xcode/DerivedData DocumentationCache iOS DeviceSupport UserData CoreSimulator/Devices Before deleting anything, I’d like to understand which of these folders are safe to clean up, and what the potential side effects might be (for example, rebuild times, simulator re-downloads, etc.). What is the recommended best practice to manage disk space when using Xcode on a low-storage machine? Thanks in advance for your help.

I am developing a binary SDK for consumption by others. When we updated to Xcode 26, any builds which are generated cannot be consumed by Xcode 16. The specifics lie in the optionals. The following Swift code generate a .swiftmodule func affectedApi() -> Int? { return 1 } In Xcode 16 it generated the following .swiftmodule in the framework. public func affectedIntApi() -> Swift.Int? In Xcode 26 it adds an "if" statement. #if compiler(>=5.3) && $NonescapableTypes public func affectedIntApi() -> Swift.Int? #endif That if statement prevents Xcode16 from seeing the API, and it causes compile failures. This happens regardless of which Swift version is used, and it only affects functions which use Optionals. Is there a way to prevent the compiler from wrapping the API in that statement?

Hello all! My name is Luke, and I'm a 14 year old with a idea for SSC. This is my first SSC submission ever. I would like some feedback concerning a question. My app is an AI powered academic planner that helps you and your life. It uses a mini on-device LLM to help organize assignments. This is a real business I am building, and I put inside of my app simulated features such as the app saying "scanning your Google Classroom..", would this go against any terms and make the app less likely to win? I also have my app fully polished, and feels like an actual app and finished product, with demo assignments pre-loaded, and most stuff is placeholders. Should the app be more like a guided simulator? Such as "click here to see how this will be simulated in a final release" or again should it be polished? I just want some feedback, since I only have 3 minutes, and the app needs to be offline, I just want to improvise. You can check out the basis of my app at my website. https://whiteb0x.me Hopefully I can get some feedback from the community, and/or ex winners! Thanks all! - Luke

Prior to iOS 26.0 we were able to download specific simulator runtimes from the command line by using a command like xcodebuild -downloadPlatform iOS -buildVersion 18.0 This is described in the documentation here. This no longer works for 26.x. If I run the following command: "xcodebuild -downloadPlatform iOS -buildVersion 26.0" it fails with the following error: "Finding content... iOS 26.0 is not available for download." If I omit the -buildVersion flag it will download the latest version, currently 26.2, but if I try and specify 26.2 as the buildVersion I still get "iOS 26.2 is not available for download". This behavior has been confirmed on Xcode 26.2. Perhaps related, it appears these runtimes are also no longer being made available for download on https://developer.apple.com/download/all

The documentation of the NSPopover property hasFullSizeContent says that when it's true, you should Use the safeAreaLayoutGuide of the contentViewController view to ensure that your content is fully visible and doesn’t become clipped when displayed. I can do that by adding auto-layout constraints programmatically, but is there a way to do it in the xib? When I googled it, the AI summary begins To use safe areas in a Mac XIB (Interface Builder), enable the "Use Safe Area Layout Guides" checkbox in the File Inspector for your view but I have not found any non-AI indications that such a checkbox exists for macOS. (I'm using Xcode 26.2.)

When attempting to access the (Certificates Identifiers & Profiles) page, I receive the message "Unable to find a team with the given Team ID to which you belong". Even while set as a developer or as an admin I still receive the same message above.

Each time I try to launch Xcode 26, it immediately crashes in SourceEditorDataSource.ideChat_gracefullyApplyChangesToReflect. I'm now no longer able to use Xcode. A partial crash log attached. So far I've tried deleting derived data, rebooting, deleting ~/Library/Caches/com.apple.dt.Xcode. What should I do? Thank you in advance for any help. crash-report.txt

I used to develop iPhone apps about a decade ago and am now back at it with an iPhone and companion Apple Watch app. Why does it suck so bad? I a must be doing something wrong, but what I am doing is out of the box. The majority of the time when I go to build on the watch I get: Previous preparation error: A connection to this device could not be established.; Timed out while attempting to establish tunnel using negotiated network parameters. Which I then first try to force quit the app on the watch and if that does not work, reboot the watch (which is pretty ridiculous). I tried Gemini and it gave me the following explanation: This is arguably the single most frustrating error in the entire watchOS development ecosystem. As an expert, I can tell you that you are not doing anything wrong; you are fighting a fragile architecture. Here is the technical breakdown of why this happens and a workflow to mitigate it without constant reboots. The Technical "Why" This error message reveals that the issue lies in the CoreDevice (and formerly usbmuxd) infrastructure, specifically in the secure transport layer. The "Tunnel" Failure: Xcode attempts to establish a secure, encrypted tunnel (DTXConnection) to the Apple Watch to push the debugger and the app binary. Unlike the iPhone, which can sustain a high-bandwidth connection easily, the Watch aggressively manages its radios (Bluetooth vs. WiFi vs. AWDL) to save battery. The "Handshake" Timeout: If the Watch is on Bluetooth (Low Energy) when Xcode initiates the tunnel, the bandwidth is insufficient. The system tries to escalate the connection to WiFi (or Apple Wireless Direct Link). If this negotiation takes even a few milliseconds too long—due to 2.4GHz interference, router mDNS configuration, or the Watch CPU being throttled—the handshake times out. The "Previous Preparation Error": This is the insidious part. Once the handshake fails once, Xcode’s device service caches that failure state for the device UUID. It marks the device as "unreachable" to prevent the IDE from hanging indefinitely on subsequent tries. Why you see it constantly: You aren't actually triggering a new connection attempt; you are hitting the cached "failed" state immediately. Unfortunately, the solutions it gives me are: The "Wired Proxy" Method (Most Reliable) This is the gold standard for watchOS debugging. Do not rely on "Connect via Network" for the Watch directly if you can avoid it. Disable WiFi on your Mac (temporarily) or ensure the Mac and iPhone are on the exact same SSID. Plug your iPhone into the Mac via USB. Ensure the Watch is paired to that iPhone. Result: Xcode will tunnel the instructions through the USB connection to the Phone, and the Phone acts as a high-bandwidth proxy to the Watch. This eliminates the "Mac-to-Watch" WiFi negotiation failure point. Do you hit this regularly? What do you do to make for a smooth development and deployment process? Or is it really this fragile? Thanks for any help! Bryan

I've suddenly started seeing hundreds of the same block of four error messages (see attached image) when running my app on my iOS device through Xcode. I've tried Cleaning the Build folder, but I keep seeing these messages in the console but can't find anything about them. Phone is running iOS 26.1. Xcode is at 16.4. Mac is on Sequoia 15.5. The app is primarily a MapKit SwiftUI based application. Messages below: Connection error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service named com.apple.PerfPowerTelemetryClientRegistrationService was invalidated: Connection init failed at lookup with error 159 - Sandbox restriction." UserInfo={NSDebugDescription=The connection to service named com.apple.PerfPowerTelemetryClientRegistrationService was invalidated: Connection init failed at lookup with error 159 - Sandbox restriction.} (+[PPSClientDonation isRegisteredSubsystem:category:]) Permission denied: Maps / SpringfieldUsage (+[PPSClientDonation sendEventWithIdentifier:payload:]) Invalid inputs: payload={ isSPR = 0; } CAMetalLayer ignoring invalid setDrawableSize width=0.000000 height=0.000000 I'm also seeing the following error messages: CoreUI: CUIThemeStore: No theme registered with id=0

Trying to develop a little Watch app in Swift, and it's been kind of a miserable experience. I constantly get transport errors trying to connect to my watch. I've tried the trick of putting the Mac and the watch on my iPhone hotspot instead of just on the same WiFi network, but I am not sure that actually helps. I can run maybe once or twice, and then the transport error happens and it's very hard to get XCode to recognize the watch again. Also, when it DOES connect, it seems that XCode almost always loses the debugging connection (I just continue, and it IS actually running on the Watch at that point, but no debugger).

I'm trying to manage multiple Command Line Tools versions side-by-side (e.g., 16.2 and 26.2). I renamed the CLT directory to /Library/Developer/CommandLineTools-26.2.0 and set: xcode-select -s /Library/Developer/CommandLineTools-26.2.0 or DEVELOPER_DIR=/Library/Developer/CommandLineTools-26.2.0 Both result in: c++: error: unable to find Xcode installation from active developer path "/Library/Developer/CommandLineTools-26.2.0" It appears CLT only works at the fixed path /Library/Developer/CommandLineTools, unlike Xcode which can be at any location. Is this by design? Is there a supported way to use multiple CLT versions in parallel, similar to how multiple Xcode versions can coexist?

I'm trying to download an iOS Simulator runtime in Xcode 26.2 or 26.1 on macOS 26.1, but the download keeps failing with the following error: Download failed. Domain: DVTDownloadableErrorDomain Code: 41 Failed fetching catalog for assetType (com.apple.MobileAsset.iOSSimulatorRuntime), serverParameters ({ RequestedBuild = 23C54;}) Domain: DVTDownloadsUtilitiesErrorDomain. Code: -1. Download failed due to a bad URL. (Catalog download for com.apple.MobileAsset.iOSSimulatorRuntime) Domain: com.apple.MobileAssetError.Download Code: 49 User Info: {checkConfiguration = 1;} macOS &amp; Xcode Info: macOS Version: 26.1 (Build 25B78) Xcode Version: 26.2 (24553) (Build 17C52) What I've tried so far: Formatted my Mac and reinstalled Xcode multiple times. Completely deleted Xcode and its related files several times (/Applications/Xcode.app, caches, preferences). Tried different internet connections from multiple locations. Checked Apple servers and verified network. Attempted downloading other simulator runtimes (fail). but download fails immediately with DVTDownloadableErrorDomain Code 41 and bad URL error. Question: How can I fix the simulator download issue in Xcode 26.2 on macOS 26.1? Is there a known workaround for the bad URL / catalog download error?

I know this post isn't going to give a lot of details, but what I experienced tonight was so completely weird that I wanted to get it posted here in case others run into it: FIRST: All was well until I made a trivial change to a large Objective-C++ module. I suddenly got the idea to look at that line in the code review pane, to see if that area of code had ever had recent modifications. But, the entire module showed up as modified -- one giant change bar, with nothing on the right side of the code review pane, no matter what commit I selected. Then I noticed that the two lines of code which had all of 4 characters edited were no longer showing any change bars. Yet, the file showed up as "modified". Still, the exact line changes were not showing in the source code navigator, even though other files showed their changes. Note I'm connected to our remote repo on github. I did some command line git checks of the local repo, and the changes were there (as yet unstaged). So -- I figured, I'm gonna ask the Apple Coding Assistant what's up. And it gave some fantastic advice, especially on how to confirm the changes really were in the repo ready to stage and commit and push. Which I did. But despite following a couple hours of wonderful suggestions, I could never get the change bars back -- for this one specific file! (yes, the file was in the repo, and in the project -- everything seemed OK with the file itself -- nothing had changed in the project, which compiled and ran perfectly with my changes). SECOND -- suddenly, the AI assistant seemed to crash Xcode. When I went to re-run Xcode, it just crashed exactly the same. The crash log indicated "Xcode is crashing inside the IDEIntelligenceChat plugin while it’s trying to “apply changes” to a Source Editor buffer". Ultimately, I needed to restart Xcode holding down the SHIFT key. I could open other projects, but not the one I had been working on. So I turned OFF apple Intelligence (thanks, ChatGPT). That allowed me to launch. It sounds like some sort of corrupt Apple Intelligence chat logs and/or caches, which ChatGPT has given me extensive suggestions for deleting. I don't have the energy to attack that tonight -- I did an additional Time Machine backup and hope to take a closer look tomorrow. Ideally -- I'd rather NOT lose all my on-going coding assistant chats for this project -- I had some ongoing suggestions I was working on. But more concerning is the weirdness with changebars affecting this one 7,000 line .mm file. It doesn't seem like there's anything that should affect those change bars for ONE FILE that is in the repo and where changes can be seen from a git diff command line operation. If it's a bug -- I can live with it. But it's worrisome. Other than that, Xcode 26.2 has been running great! Unlike 26.1, which insisted on re-compiling all 600 files in my project every time I ran/debugged, 26.2 just does the 2-6 modified files -- a perfect incremental compile. I've saved HOURS of wasted unnecessary compilation since 26.2 was released.

Hi, I’m facing a consistent simulator boot issue that appears to start after iOS 18.2 simulator runtimes and persists in 18.6, 26.1, and 26.2. Observed behavior iOS 18.2 simulator works fine iOS 18.6 simulator does NOT boot iOS 26.1 / 26.2 simulators do NOT boot Tried everything reinstall/clear cache and all and event formatted the system Unable to boot the Simulator NSPOSIXErrorDomain Code: 4 Failure Reason: Interrupted system call Failed to start launchd_sim: could not bind to session, launchd_sim may have crashed or quit responding macOS: Sequoia Xcode: 26.1, 26.2 Machine: Apple Silicon Unable to boot the Simulator. Domain: NSPOSIXErrorDomain Code: 4 Failure Reason: Interrupted system call User Info: { DVTErrorCreationDateKey = "2025-12-26 02:19:27 +0000"; IDERunOperationFailingWorker = "_IDEInstalliP.honeSimulatorWorker", Session = "com apple CoreSimulator.SimDevice CCDECA56-4A59-491B-A830-0F3928FCD957"; } Failed to start launchd_sim: could not bind to session, launchd_sim may have crashed or quit responding Domain: com.apple.SimLaunchHostService.RequestError Code: 4 Event Metadata: com.apple. dt. DERunOperationWorkerFinished : { "device_identifier" = "CCDECAE6-4A59-491B-A830-0E3928FCD957"; "device_model" = "iPhone18, 1"; "device_osBuild" = "26.1 (23B86)"; "device_osBuild_monotonic" = 2301008600; "device_os_variant" = 1; "device_platform" = "com apple.platform.iohonesimulator"; "device_platform_family" = 2; "device_reality" = 2; "device_thinningType" = "iPhone18,1"; "device_transport" = 4; "launchSession_schemeCommand" = Run; "launchSession_schemeCommand_enum" = 1; "launchSession_targetArch" = arm64; "launchSession_targetArch_enum" = 6; "operation_duration_ms" = 1183; "operation_errorCode" = 4; "operation_errorDomain" = NSPOSIXErrorDomain; "operation_errorWorker" = "_IDEInstalliPhoneSimulatorWorker"; "operation_error_reportable" = 1; "operation_name" = IDERunOperationWorkerGroup; "param_consoleMode" = 1; "param_debugger_attachToExtensions" = 0; "param_debugger_attachToXPC" = 1; "param_debugger_type" = 3; "param_destination_isProxy" = 0; "param_destination_platform" = "com apple platform Please help on this as it got stuck. Thanks

Hi, I have started facing an issue with Xcode since updating to macOS 26.1. The debugger is not stopping at breakpoints in Objective-C code, however breakpoints in Swift file are working fine. I am using Xcode 16.4. For breakpoints in Objective-C files I have started to get this message since the OS update - 'Xcode won't pause at this breakpoint because it has not been resolved.' I have already tried cleaning derived data and build folder. I do not want to upgrade to Xcode 26. Could someone help with the fix? Thanks