chore: raise minimum supported platform, Swift, and Xcode versions (#4271)

* chore: raise minimum supported platform, Swift, and Xcode versions

Apple has required Xcode 26 and the 26 SDKs for App Store Connect uploads
since April 28, 2026. Per the support policy in README.md, Amplify Swift
tracks the Swift version shipped with the minimum Xcode allowed for App
Store Connect uploads.

Platform floors now match Apple's published Xcode 26 support matrix, and
the Swift toolchain floor matches AWS SDK for Swift:

- iOS 13 -> 15
- tvOS 13 -> 15
- macOS 12 (unchanged)
- watchOS 9 (unchanged, already above Apple's floor of 8)
- visionOS: declared in Package.swift for the first time, promoted to GA
- swift-tools-version 5.9 -> 6.0
- Minimum Xcode 16.0 -> 26.0

Adopting the Swift 6 language mode is deliberately out of scope. Raising
swift-tools-version to 6.0 would otherwise flip the default language mode
to Swift 6, so `swiftLanguageModes: [.v5]` pins the existing behavior and
keeps this change behavior-neutral. The strict-concurrency migration is
tracked separately.

CI:
- Runners moved from macos-15 to macos-26
- Latest Xcode 26.3 -> 26.5; minimum 16.0.0 -> 26.0.1
- Removed the Xcode 16 legs and the duplicate hardcoded 16.4.0 pins
- Simulator devices updated to those present on macos-26 (iPhone 17 Pro
  Max, Apple Watch Series 11); minimum-Xcode legs use the 26.2 runtime
  because the image ships 26.0 SDKs but installs no 26.0 runtime
- visionOS added to the minimum-supported-version build matrix, which
  previously never exercised the platform the docs call supported
- Added an advisory, non-blocking nightly build against the Xcode 27
  preview image for early warning on the next Xcode release

Docs: corrected the stale Xcode 13.4 requirement in CONTRIBUTING.md.

Three test files were reformatted because raising swiftformat's
--swiftversion to 6.0 activates the preferCountWhere rule.

* fix(predictions): exclude CoreML predictions plugin from tvOS explicitly

The tvOS build failed with "'SFSpeechRecognitionResult' is unavailable in
tvOS". SFSpeechRecognitionResult is marked API_UNAVAILABLE(tvos), and the
CoreML predictions plugin was relying on `#if canImport(Speech)` to compile
itself out on tvOS.

As of the Xcode 26 SDKs, the tvOS Speech framework ships a module
(module.modulemap and Speech.swiftmodule), so canImport(Speech) now
succeeds on tvOS while the type itself remains unavailable. The guard
silently stopped excluding the platform.

Verified this is an SDK change and not a consequence of raising the tvOS
deployment floor: the same file fails to compile against the Xcode 26 tvOS
SDK at both tvos13.0 and tvos15.0.

Adding `&& !os(tvOS)` restores the pre-Xcode-26 behavior. Applied to every
file in the CoreML plugin rather than only the Speech types, because the
plugin's configure/reset/client-behavior files reference those types and
were previously compiled out as a unit.

Verified by building CoreMLPredictionsPlugin and AWSPredictionsPlugin for
arm64-apple-tvos15.0-simulator, and confirming macOS still compiles
CoreMLPredictionService so the plugin stays active where Speech is
genuinely available.

* chore: raise host app iOS deployment targets to match the new floor

Integration tests failed to build with:

  compiling for iOS 14.0, but module 'Amplify' has a minimum deployment
  target of iOS 15.0

Raising the package floor to iOS 15 left four Xcode projects behind, so they
still tried to link an Amplify built for a newer target than their own:

  APIHostApp            13.0 -> 15.0
  DataStoreHostApp      13.0 -> 15.0
  PredictionsHostApp    14.0 -> 15.0
  canaries/example      14.4 -> 15.0

Checked the other platforms for the same gap and found none: watchOS host
apps are at 9.0/9.4/10.0 against a floor of 9, tvOS is at 16.4 against 15,
macOS is at 14.6/15.0 against 12, and StorageHostApp's Base.xcconfig was
already 15.0/12.0.

Author: harsh62

.github/composite_actions/get_platform_parameters/action.yml

@@ -41,8 +41,8 @@ runs:
 
     - id: get-xcode-version
       run: |
-        LATEST_XCODE_VERSION=26.3
-        MINIMUM_XCODE_VERSION=16.0.0
+        LATEST_XCODE_VERSION=26.5
+        MINIMUM_XCODE_VERSION=26.0.1
 
         INPUT_XCODE_VERSION=${{ inputs.xcode_version }}
 
@@ -66,60 +66,49 @@ runs:
 
         # Map resolved Xcode versions to simulator destinations.
         # Only explicitly supported versions are allowed — unknown versions fail.
+        #
+        # The minimum-Xcode legs (26.0.1) run against the 26.2 simulator runtime:
+        # the macos-26 runner image ships SDKs for 26.0 but only installs runtimes
+        # for 26.2 and later. The Xcode version is what we are validating here, and
+        # the runtime only needs to be at or above our deployment target floors.
         case $INPUT_PLATFORM/$XCODE_VERSION in
-          iOS/26.3)
-            DEVICE="iPhone 16 Pro Max"
-            OS_VERSION="26.2"
-            ;;
-          iOS/16.4.0)
-            DEVICE="iPhone 16 Pro Max"
-            OS_VERSION="18.5"
+          iOS/26.5)
+            DEVICE="iPhone 17 Pro Max"
+            OS_VERSION="26.5"
             ;;
-          iOS/16.0.0)
-            DEVICE="iPhone 16 Pro Max"
-            OS_VERSION="18.0"
-            ;;
-          tvOS/26.3)
-            DEVICE="Apple TV 4K (3rd generation)"
+          iOS/26.0.1)
+            DEVICE="iPhone 17 Pro Max"
             OS_VERSION="26.2"
             ;;
-          tvOS/16.4.0)
+          tvOS/26.5)
             DEVICE="Apple TV 4K (3rd generation)"
-            OS_VERSION="18.5"
+            OS_VERSION="26.5"
             ;;
-          tvOS/16.0.0)
+          tvOS/26.0.1)
             DEVICE="Apple TV 4K (3rd generation)"
-            OS_VERSION="18.0"
-            ;;
-          watchOS/26.3)
-            DEVICE="Apple Watch Series 10 (46mm)"
             OS_VERSION="26.2"
             ;;
-          watchOS/16.4.0)
-            DEVICE="Apple Watch Series 10 (46mm)"
-            OS_VERSION="11.5"
-            ;;
-          watchOS/16.0.0)
-            DEVICE="Apple Watch SE (44mm) (2nd generation)"
-            OS_VERSION="11.0"
+          watchOS/26.5)
+            DEVICE="Apple Watch Series 11 (46mm)"
+            OS_VERSION="26.5"
             ;;
-          visionOS/26.3)
-            DEVICE="Apple Vision Pro"
+          watchOS/26.0.1)
+            DEVICE="Apple Watch Series 11 (46mm)"
             OS_VERSION="26.2"
             ;;
-          visionOS/16.4.0)
+          visionOS/26.5)
             DEVICE="Apple Vision Pro"
-            OS_VERSION="2.5"
+            OS_VERSION="26.5"
             ;;
-          visionOS/16.0.0)
+          visionOS/26.0.1)
             DEVICE="Apple Vision Pro"
-            OS_VERSION="2.0"
+            OS_VERSION="26.2"
             ;;
           macOS/*)
             ;;
           *)
             echo "Unsupported platform/Xcode combination: $INPUT_PLATFORM/$XCODE_VERSION"
-            echo "Supported Xcode versions: 26.3, 16.4.0, 16.0.0"
+            echo "Supported Xcode versions: 26.5, 26.0.1"
             exit 1
             ;;
         esac

.github/composite_actions/install_simulators_if_needed/action.yml

@@ -19,7 +19,7 @@ runs:
       run: |
         XCODE_VERSION="${{ inputs.xcode_version }}"
         PLATFORM="${{ inputs.platform }}"
-        DEFAULT_XCODE_VERSION="16.4.0"
+        DEFAULT_XCODE_VERSION="26.5"
 
         # Skip for macOS as it doesn't need simulators
         if [[ "$PLATFORM" == "macOS" ]]; then

.github/composite_actions/run_xcodebuild/action.yml

@@ -14,7 +14,7 @@ inputs:
   destination:
     required: false
     type: string
-    default: 'platform=iOS Simulator,name=iPhone 13,OS=latest'
+    default: 'platform=iOS Simulator,name=iPhone 17 Pro Max,OS=latest'
   sdk:
     required: false
     type: string

.github/workflows/api-breaking-changes-detection.yml

@@ -10,7 +10,7 @@ permissions:
 jobs:
   build-and-check-api-breakage:
     name: Build and Check API Breakage
-    runs-on: macos-15
+    runs-on: macos-26
 
     steps:
     - name: Checkout repository

.github/workflows/api_digester_check.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   check-swift-api-digester:
-    runs-on: macos-15
+    runs-on: macos-26
 
     steps:
     - name: Checkout repository

.github/workflows/build_minimum_supported_swift_platforms.yml

@@ -22,12 +22,12 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        platform: [iOS, macOS, tvOS, watchOS]
+        platform: [iOS, macOS, tvOS, watchOS, visionOS]
 
     uses: ./.github/workflows/build_scheme.yml
     with:
       scheme: Amplify-Build
-      os-runner: 'macos-15'
+      os-runner: 'macos-26'
       xcode-version: 'minimum'
       platform: ${{ matrix.platform }}
       save_build_cache: false

.github/workflows/build_scheme.yml

@@ -16,7 +16,7 @@ on:
 
       os-runner:
         type: string
-        default: 'macos-15'
+        default: 'macos-26'
 
       save_build_cache:
         type: boolean

.github/workflows/canary.yml

@@ -16,14 +16,16 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-15
-            xcode-version: '26.3'
-            device: 'iPhone 16 Pro Max'
+          - os: macos-26
+            xcode-version: '26.5'
+            device: 'iPhone 17 Pro Max'
+            version: '26.5'
+          # Minimum supported Xcode. Uses the 26.2 runtime because the macos-26
+          # image does not install a 26.0 simulator runtime.
+          - os: macos-26
+            xcode-version: '26.0.1'
+            device: 'iPhone 17 Pro Max'
             version: '26.2'
-          - os: macos-15
-            xcode-version: '16.4.0'
-            device: 'iPhone 16 Pro Max'
-            version: '18.5'
     name: Canary Test - Xcode ${{ matrix.xcode-version }}
     runs-on: ${{ matrix.os }}
     steps:

.github/workflows/integ_test_auth.yml

@@ -62,13 +62,13 @@ jobs:
       project_path: ./AmplifyPlugins/Auth/Tests/AuthHostedUIApp/
       resource_subfolder: auth
       timeout-minutes: 60
-      xcode_version: '16.4.0'
+      xcode_version: 'latest'
     secrets: inherit
 
   auth-webauthn-integration-test-iOS:
     if: ${{ inputs.webauthn-ios != 'false' }}
     name: Auth WebAuthn Integration Tests (iOS)
     uses: ./.github/workflows/integ_test_auth_webauthn.yml
     with:
-      xcode_version: '16.4.0'
+      xcode_version: 'latest'
     secrets: inherit

.github/workflows/integ_test_auth_webauthn.yml

@@ -14,7 +14,7 @@ permissions:
 jobs:
   auth-webauthn-integration-tests:
     name: iOS Tests | AuthWebAuthnApp
-    runs-on: macos-15
+    runs-on: macos-26
     timeout-minutes: 60
     environment: IntegrationTest