Developing iOS Apps

Develops iOS/macOS apps with XcodeGen, SwiftUI, and SPM, including Apple Developer signing, notarization, and CI/CD pipelines. Use when building iOS/macOS apps, fixing Xcode build failures, deploying to real devices, or configuring CI/CD signing. Triggers on XcodeGen project.yml, SPM dependency issues, code signing errors (Error -25294, keychain mismatch, adhoc fallback, EMFILE, notarization credential conflict), "Library not loaded @rpath", Electron @electron/osx-sign / @electron/notarize, notarytool, or certificate/provisioning problems.

Mobile App Development|v1|Updated 7/2/2026|GitHub source

MCP get_skill({ skillId: "developing-ios-apps-4a39681d" })

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# iOS App Development

Build, configure, and deploy iOS applications using XcodeGen and Swift Package Manager.

## Critical Warnings

| 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](#spm-dynamic-framework-not-embedded) |
| `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](#camera--avfoundation) |
| App signed as adhoc despite certificate | `@electron/packager` defaults `continueOnError: true` | Set `continueOnError: false` in osxSign. See [Code Signing](#macos-code-signing--notarization) |
| "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](#macos-code-signing--notarization) |
| 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](#macos-code-signing--notarization) |

## Quick Reference

| 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` |

## XcodeGen Configuration

### Minimal project.yml

```yaml
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

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