I have the same issue, but it's not a unity project, on some of my Pods I'm getting the same error. If I change the #import from "something.h" to <something.h> it then says framework in <> not found use quotes instead! Can't get it to import them successfully.

Here I am late to the party as usual I've just asked a related question before stumbling upon this thread : https://discussions.apple.com/thread/255363612 I too am looking to use the iPhone 15 Pro's USB C port to talk to devices over serial, for what is an experiment I don't want to spend almost £100 on a Redpark cable. I was hoping to get a cheap USB C to UART/FTDI adapter and plug it in, it's looking like this is less and less likely as a possibility. I know an IP to Serial bridge is an option but I would prefer the flexibility of a direct cable which doesn't need external power and additional dependencies. I did see that Terminus now supports USB Serial using the Redpark cable, and I'm wondering if that is via a generic Apple framework or using the Redpark SDK.

I plan to ignore HomeKit barcodes for the moment, so I'm now concentrating on the Matter side of things. However I cannot get Xcode to recognise MTRSetupPayload even after importing HomeKit and MatterSupport I just get "Cannot find 'MTRSetupPayload' in scope" After rummaging around in the documentation links you provided I did come across this: Apple Developer Onboarding A Matter Device Which looks to be an example of almost exactly what I am trying to achieve, however it's outdated and a lot of the references are deprecated. When trying to modify this with the new methods I again come across the issue of being unable to declare MTRSetupPayload.

I am receiving the same errors on Xcode 16.3 (16E140), using SwiftData but only simply types like String and Date with no transformations.

Excellent thank you for you replies, I haven't 100% tested this yet, but using a valid matter setup QR the below code launches the "Add Device to Home UI" and accepts the code, recognises the device type etc .. import HomeKit import Matter func registerMatterDevice(onboardingCode: String) async { let payload = MTRSetupPayload(payload: onboardingCode) guard let setupPayload = payload else { print("Invalid Matter onboarding code") return } let request = HMAccessorySetupRequest() request.matterPayload = setupPayload let setupManager = HMAccessorySetupManager() _ = try? await setupManager.performAccessorySetup(using: request) } This will hopefully let me get to where I want to be. Thank you very much.