No idea if I did something wrong initially, but I fixed it with these steps: Download repo from https://github.com/apple/unityplugins/tree/main Start building the libraries python3 build.py -p Core GameKit -m iOS macOS Let script codesign the libraries During the build process copy the line the shell script outputs to codesign (similar to this): codesign --force --sign ABCDEFGHIJKLMN1234567890 --timestamp=none --preserve-metadata=identifier,entitlements,flags --generate-entitlement-der /path/to/bundle After the build script finished, you can find the tarball at /unityplugins-main/Build/com.apple.unityplugin.core-3.1.1.tgz Unzip the tgz and modify the Info.plist in the unziped folder /package/NativeLibraries~/Release/iOS/AppleCoreNative.framework/Info.plist You should add the missing CFBundleShortVersionString like this: <key>CFBundleShortVersionString</key> <string>1.0</string> Afterwards, codesign the bundle again with the prompt copied at 2.2. Use this path from the unziped folder /package/NativeLibraries~/Release/iOS/AppleCoreNative.framework/AppleCoreNative Now export the folder back to a tarball using tar -czvf com.apple.unityplugin.core-3.1.1.tgz package Simply import the tarball from Unity Package Manager and restart archiving iOS build

I have the same problem. Did you find a solution for it?