Develops iOS/macOS applications with XcodeGen, SwiftUI, and SPM. Handles Apple Developer signing, notarization, and CI/CD pipelines. Triggers on XcodeGen project.yml, SPM dependency issues, device deployment, code signing errors (Error -25294, keychain mismatch, adhoc fallback, EMFILE, notarization credential conflict, continueOnError), camera/AVFoundation debugging, iOS version compatibility, "Library not loaded @rpath", Electron @electron/osx-sign/@electron/notarize config, notarytool, GitHub Actions secrets in conditionals, or certificate/provisioning problems. Use when building iOS/macOS apps, fixing Xcode build failures, deploying to real devices, or configuring CI/CD signing pipelines.
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npx tessl i github:fernandezbaptiste/claude-code-skills --skill developing-ios-apps100
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Build, configure, and deploy iOS applications using XcodeGen and Swift Package Manager.
| Issue | Cause | Solution |
|---|---|---|
| "Library not loaded: @rpath/Framework" | XcodeGen doesn't auto-embed SPM dynamic frameworks | Build in Xcode GUI first (not xcodebuild). See Troubleshooting |
xcodegen generate loses signing | Overwrites project settings | Configure in project.yml target settings, not global |
| Command-line signing fails | Free Apple ID limitation | Use Xcode GUI or paid developer account ($99/yr) |
| "Cannot be set when automaticallyAdjustsVideoMirroring is YES" | Setting isVideoMirrored without disabling automatic | Set automaticallyAdjustsVideoMirroring = false first. See Camera |
| App signed as adhoc despite certificate | @electron/packager defaults continueOnError: true | Set continueOnError: false in osxSign. See Code Signing |
| "Cannot use password credentials, API key credentials..." | Passing teamId to @electron/notarize with API key auth | Remove teamId. notarytool infers team from API key. See Code Signing |
| EMFILE during signing (large embedded runtime) | @electron/osx-sign traverses all files in .app bundle | Add ignore filter + ulimit -n 65536 in CI. See Code Signing |
| Task | Command |
|---|---|
| Generate project | xcodegen generate |
| Build simulator | xcodebuild -destination 'platform=iOS Simulator,name=iPhone 17' build |
| Build device (paid account) | xcodebuild -destination 'platform=iOS,name=DEVICE' -allowProvisioningUpdates build |
| Clean DerivedData | rm -rf ~/Library/Developer/Xcode/DerivedData/PROJECT-* |
| Find device name | xcrun xctrace list devices |
name: AppName
options:
bundleIdPrefix: com.company
deploymentTarget:
iOS: "16.0"
settings:
base:
SWIFT_VERSION: "6.0"
packages:
SomePackage:
url: https://github.com/org/repo
from: "1.0.0"
targets:
AppName:
type: application
platform: iOS
sources:
- path: AppName
settings:
base:
INFOPLIST_FILE: AppName/Info.plist
PRODUCT_BUNDLE_IDENTIFIER: com.company.appname
CODE_SIGN_STYLE: Automatic
DEVELOPMENT_TEAM: TEAM_ID_HERE
dependencies:
- package: SomePackagePersonal (free) account: Works in Xcode GUI only. Command-line builds require paid account.
# In target settings
settings:
base:
CODE_SIGN_STYLE: Automatic
DEVELOPMENT_TEAM: TEAM_ID # Get from Xcode → Settings → AccountsGet Team ID:
security find-identity -v -p codesigning | head -3| iOS 17+ Only | iOS 16 Compatible |
|---|---|
.onChange { old, new in } | .onChange { new in } |
ContentUnavailableView | Custom VStack |
AVAudioApplication | AVAudioSession |
@Observable macro | @ObservableObject |
| SwiftData | CoreData/Realm |
project.yml:deploymentTarget:
iOS: "16.0"// iOS 17
.onChange(of: value) { oldValue, newValue in }
// iOS 16
.onChange(of: value) { newValue in }
// iOS 17
ContentUnavailableView("Title", systemImage: "icon")
// iOS 16
VStack {
Image(systemName: "icon").font(.system(size: 48))
Text("Title").font(.title2.bold())
}
// iOS 17
AVAudioApplication.shared.recordPermission
// iOS 16
AVAudioSession.sharedInstance().recordPermissionxcodegen generateCmd + R)xcodebuild \
-project App.xcodeproj \
-scheme App \
-destination 'platform=iOS,name=DeviceName' \
-allowProvisioningUpdates \
build| Error | Solution |
|---|---|
| "Library not loaded: @rpath/Framework" | SPM dynamic framework not embedded. Build in Xcode GUI first, then CLI works |
| "No Account for Team" | Add Apple ID in Xcode Settings → Accounts |
| "Provisioning profile not found" | Free account limitation. Use Xcode GUI or get paid account |
| Device not listed | Reconnect USB, trust computer on device, restart Xcode |
| DerivedData won't delete | Close Xcode first: pkill -9 Xcode && rm -rf ~/Library/Developer/Xcode/DerivedData/PROJECT-* |
| Feature | Free Apple ID | Paid ($99/year) |
|---|---|---|
| Xcode GUI builds | ✅ | ✅ |
| Command-line builds | ❌ | ✅ |
| App validity | 7 days | 1 year |
| App Store | ❌ | ✅ |
| CI/CD | ❌ | ✅ |
Root Cause: XcodeGen doesn't generate the "Embed Frameworks" build phase for SPM dynamic frameworks (like RealmSwift, Realm). The app builds successfully but crashes on launch with:
dyld: Library not loaded: @rpath/RealmSwift.framework/RealmSwift
Referenced from: /var/containers/Bundle/Application/.../App.app/App
Reason: image not foundWhy This Happens:
embed: true in project.yml causes build errors (XcodeGen limitation)The Fix (Manual, one-time per project):
After Manual Fix: Command-line builds (xcodebuild) will work because Xcode persists the embed setting in project.pbxproj.
Identifying Dynamic Frameworks:
# Check if a framework is dynamic
file ~/Library/Developer/Xcode/DerivedData/PROJECT-*/Build/Products/Debug-iphoneos/FRAMEWORK.framework/FRAMEWORK
# Dynamic: "Mach-O 64-bit dynamically linked shared library"
# Static: "current ar archive"packages:
AudioKit:
url: https://github.com/AudioKit/AudioKit
from: "5.6.5"
RealmSwift:
url: https://github.com/realm/realm-swift
from: "10.54.6"
targets:
App:
dependencies:
- package: AudioKit
- package: RealmSwift
product: RealmSwift # Explicit product name when package has multiplegit config --global http.proxy http://127.0.0.1:1082
git config --global https.proxy http://127.0.0.1:1082
xcodebuild -scmProvider system -resolvePackageDependenciesNever clear global SPM cache (~/Library/Caches/org.swift.swiftpm). Re-downloading is slow.
Camera preview requires real device (simulator has no camera).
NSCameraUsageDescription to Info.plist?session.startRunning() called on background thread?automaticallyAdjustsVideoMirroring before setting isVideoMirrored?CRITICAL: Must disable automatic adjustment before setting manual mirroring:
// WRONG - crashes with "Cannot be set when automaticallyAdjustsVideoMirroring is YES"
connection.isVideoMirrored = true
// CORRECT - disable automatic first
connection.automaticallyAdjustsVideoMirroring = false
connection.isVideoMirrored = trueUIViewRepresentable in ZStack may have zero bounds. Fix with explicit frame:
// BAD: UIViewRepresentable may get zero size in ZStack
ZStack {
CameraPreviewView(session: session) // May be invisible!
OtherContent()
}
// GOOD: Explicit sizing
ZStack {
GeometryReader { geo in
CameraPreviewView(session: session)
.frame(width: geo.size.width, height: geo.size.height)
}
.ignoresSafeArea()
OtherContent()
}Add logging to trace camera flow:
import os
private let logger = Logger(subsystem: "com.app", category: "Camera")
func start() async {
logger.info("start() called, isRunning=\(self.isRunning)")
// ... setup code ...
logger.info("session.startRunning() completed")
}
// For CGRect (doesn't conform to CustomStringConvertible)
logger.info("bounds=\(NSCoder.string(for: self.bounds))")Filter in Console.app by subsystem.
For detailed camera implementation: See references/camera-avfoundation.md
For distributing macOS apps (Electron or native) outside the App Store, signing + notarization is required. Without it users see "Apple cannot check this app for malicious software."
5-step checklist:
| Step | What | Critical detail |
|---|---|---|
| 1 | Create CSR in Keychain Access | Common Name doesn't matter; choose "Saved to disk" |
| 2 | Request Developer ID Application cert at developer.apple.com | Choose G2 Sub-CA (not Previous Sub-CA) |
| 3 | Install .cer → must choose login keychain | iCloud/System → Error -25294 (private key mismatch) |
| 4 | Export P12 from login keychain with password | Base64: base64 -i cert.p12 | pbcopy |
| 5 | Create App Store Connect API Key (Developer role) | Download .p8 once only; record Key ID + Issuer ID |
GitHub Secrets required (5 secrets):
| Secret | Source |
|---|---|
MACOS_CERT_P12 | Step 4 base64 |
MACOS_CERT_PASSWORD | Step 4 password |
APPLE_API_KEY | Step 5 .p8 base64 |
APPLE_API_KEY_ID | Step 5 Key ID |
APPLE_API_ISSUER | Step 5 Issuer ID |
APPLE_TEAM_IDis NOT needed.notarytoolinfers team from the API key. PassingteamIdto@electron/notarizev2.5.0 causes a credential conflict error.
Electron Forge osxSign critical settings:
osxSign: {
identity: 'Developer ID Application',
hardenedRuntime: true,
entitlements: 'entitlements.mac.plist',
entitlementsInherit: 'entitlements.mac.plist',
continueOnError: false, // CRITICAL: default is true, silently falls back to adhoc
// Skip non-binary files in large embedded runtimes (prevents EMFILE)
ignore: (filePath: string) => {
if (!filePath.includes('python-runtime')) return false;
if (/\.(so|dylib|node)$/.test(filePath)) return false;
return true;
},
// CI: explicitly specify keychain (apple-actions/import-codesign-certs uses signing_temp.keychain)
...(process.env.MACOS_SIGNING_KEYCHAIN
? { keychain: process.env.MACOS_SIGNING_KEYCHAIN }
: {}),
},Fail-fast three-layer defense:
@electron/osx-sign: continueOnError: false — signing error throws immediatelypostPackage hook: codesign --verify --deep --strict + adhoc detectionVerify signing:
security find-identity -v -p codesigning | grep "Developer ID Application"For complete step-by-step guide, entitlements, workflow examples, and full troubleshooting (7 real-world errors with root causes): references/apple-codesign-notarize.md
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