build disappears

Hi everyone, We run our CI builds on a Mac mini. On my local MacBook, incremental builds work properly and build times are fast, but on CI it looks like Xcode rebuilds everything from scratch every time, and the build is about 6 minutes slower than local. In Xcode 26, “compilation caching” became available. My understanding was that if DerivedData is preserved between CI runs, compilation caching / incremental builds should reduce build time. So I tried specifying the DerivedData path as an absolute path in our xcodebuild command to reuse it across builds. However, it still seems to do a full rebuild every time and the build time didn’t improve. Has anyone seen a similar issue with incremental builds on CI (Mac mini) with Xcode 26? Any advice on what to check or how to configure CI so incremental builds / caching actually work would be greatly appreciated. Thanks!

Trying to support undo & redo in an app that utilizes Swift Data and as with anything other than provided simplistic Apple demo examples the experience is not great. The problem: Im trying to build functionality that allows users to add items to an item group, where item and item group have a many-to-many relationship e.g. item group can hold many items and items can appear in multiple groups. When trying to do so with relatively simple setup of either adding or removing item group from items relationship array, I am pretty consistently met with a hard crash after performing undo & redo. Sometimes it works the first few undo & redos but 95% of the time would crash on the first one. Could not cast value of type 'Swift.Optional' (0x20a676be0) to 'Swift.Array' (0x207a2bc08). Where CodableStructModel is a Codable Value type inside Item. Adding and removing this relationship should be undoable & redoable as typical for Mac interaction and is supported by SwiftData by default, meaning that

Hi, Since Xcode 26.2 beta 1, till now (I thought RC or actual release will solve this issue) I have problems exporting archive to appstore via Xcode Cloud (locally everything works and using Xcode 26.2 I was able to submit app to AppStore). Build is archived successfully but during export I get an error Exporting for App Store Distribution failed. Please download the logs artifact for more information. In xcodebuild-export-archive.log I see multiple attempts & errors like this 2025-12-13T08:29:34.040644840Z 2025-12-13 00:29:33.900 xcodebuild[10889:58988] DVTServices: Sending request 9A4173F4-CD87-4A76-95FC-501B4D11EF22 to for session DVTFoundation.DVTServicesSessionProxy. 2025-12-13T08:29:34.040647258Z Method: POST 2025-12-13T08:29:34.040648780Z 2025-12-13T08:29:34.040650230Z Headers: 2025-12-13T08:29:34.040651730Z { 2025-12-13T08:29:34.040653539Z Accept = application/vnd.api+json; 2025-12-13T08:29:34.040655403Z Accept-Encoding = gzip, deflate; 2025-12-13T08:29:34.040673847Z Content-Length = 124

We are observing a reproducible issue on some (not all) iPad models equipped with A16, where BLE streaming from multiple peripherals at ≥33–40 Hz results in uneven packet distribution, burst delivery, and application-level lag. The same application, peripherals, firmware, iOS version, and physical environment do not exhibit this behaviour on A14-based iPads (iPad 10). Affected Hardware: • iPad 11 with A16 • iOS versions: identical across tested devices • Issue affects some devices of the same model, not all Internal field data • ~25 affected • ~5 unaffected • Customers actively prefer iPad 10 (A14) due to stability When two or more BLE peripherals stream data concurrently at frequencies ≥33–40 Hz, affected iPads exhibit: • Uneven packet arrival timing • Burst delivery instead of uniform intervals • Increasing latency over time • Observable application-level lag This does not present as simple packet loss. Instead, packets arrive in clusters, breaking real-time assumptions. At ≤30–33 Hz, the issue does not rep

This is just an FYI in case someone else runs into this problem. This afternoon (12 Dec 2025), I updated to macOS 26.2 and lost my network. The System Settings' Wi-Fi light was green and said it was connected, but traceroute showed No route to host. I turned Wi-Fi on & off. I rebooted the Mac. I rebooted the eero network. I switched to tethering to my iPhone. I switched to physical ethernet cable. Nothing worked. Then I remembered I had a beta of an app with a network system extension that was distributed through TestFlight. I deleted the app, and networking came right back. I had this same problem ~2 years ago. Same story: app with network system extension + TestFlight + macOS update = lost network. (My TestFlight build might have expired, but I'm not certain) I don't know if anyone else has had this problem, but I thought I'd share this in case it helps.