ci: build macOS releases with Xcode 26

Resolves #7591

This moves our CI to build macOS on Sequoia (macOS 15) with Xcode 26,
including the new macOS 26 beta SDK.

Importantly, this will make our builds on macOS 26 use the new styling.

I've added a new job that ensures we can continue to build with Xcode 16 and
the macOS 15 SDK, as well, although I think that might come to an end
when we switch over to an IconComposer-based icon. I'll verify then. For
now, we continue to support both.

I've also removed our `hasLiquidGlass` check, since this will now always
be true for macOS 26 builds.

.github/workflows/release-pr.yml

@@ -94,7 +94,7 @@ jobs:
       - name: Build Ghostty.app
         run: |
           cd macos
-          sudo xcode-select -s /Applications/Xcode_16.4.app
+          sudo xcode-select -s /Applications/Xcode_26.0.app
           xcodebuild -target Ghostty -configuration Release
 
       # We inject the "build number" as simply the number of commits since HEAD.
@@ -246,7 +246,7 @@ jobs:
       - name: Build Ghostty.app
         run: |
           cd macos
-          sudo xcode-select -s /Applications/Xcode_16.4.app
+          sudo xcode-select -s /Applications/Xcode_26.0.app
           xcodebuild -target Ghostty -configuration Release
 
       # We inject the "build number" as simply the number of commits since HEAD.

.github/workflows/release-tip.yml

@@ -173,7 +173,7 @@ jobs:
           authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
 
       - name: XCode Select
-        run: sudo xcode-select -s /Applications/Xcode_16.4.app
+        run: sudo xcode-select -s /Applications/Xcode_26.0.app
 
       # Setup Sparkle
       - name: Setup Sparkle
@@ -388,7 +388,7 @@ jobs:
           authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
 
       - name: XCode Select
-        run: sudo xcode-select -s /Applications/Xcode_16.4.app
+        run: sudo xcode-select -s /Applications/Xcode_26.0.app
 
       # Setup Sparkle
       - name: Setup Sparkle
@@ -563,7 +563,7 @@ jobs:
           authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
 
       - name: XCode Select
-        run: sudo xcode-select -s /Applications/Xcode_16.4.app
+        run: sudo xcode-select -s /Applications/Xcode_26.0.app
 
       # Setup Sparkle
       - name: Setup Sparkle

.github/workflows/test.yml

@@ -18,6 +18,7 @@ jobs:
       - build-nix
       - build-snap
       - build-macos
+      - build-macos-sequoia-stable
       - build-macos-tahoe
       - build-macos-matrix
       - build-windows
@@ -270,6 +271,46 @@ jobs:
             ghostty-source.tar.gz
 
   build-macos:
+    runs-on: namespace-profile-ghostty-macos-sequoia
+    needs: test
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      # Install Nix and use that to run our tests so our environment matches exactly.
+      - uses: cachix/install-nix-action@v31
+        with:
+          nix_path: nixpkgs=channel:nixos-unstable
+      - uses: cachix/cachix-action@v16
+        with:
+          name: ghostty
+          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
+
+      - name: Xcode Select
+        run: sudo xcode-select -s /Applications/Xcode_26.0.app
+
+      - name: get the Zig deps
+        id: deps
+        run: nix build -L .#deps && echo "deps=$(readlink ./result)" >> $GITHUB_OUTPUT
+
+      # GhosttyKit is the framework that is built from Zig for our native
+      # Mac app to access.
+      - name: Build GhosttyKit
+        run: nix develop -c zig build --system ${{ steps.deps.outputs.deps }}
+
+      # The native app is built with native Xcode tooling. This also does
+      # codesigning. IMPORTANT: this must NOT run in a Nix environment.
+      # Nix breaks xcodebuild so this has to be run outside.
+      - name: Build Ghostty.app
+        run: cd macos && xcodebuild -target Ghostty
+
+      # Build the iOS target without code signing just to verify it works.
+      - name: Build Ghostty iOS
+        run: |
+          cd macos
+          xcodebuild -target Ghostty-iOS "CODE_SIGNING_ALLOWED=NO"
+
+  build-macos-sequoia-stable:
     runs-on: namespace-profile-ghostty-macos-sequoia
     needs: test
     steps:
@@ -328,17 +369,6 @@ jobs:
       - name: Xcode Select
         run: sudo xcode-select -s /Applications/Xcode_26.0.app
 
-      # TODO(tahoe):
-      # https://developer.apple.com/documentation/xcode-release-notes/xcode-26-release-notes#Interface-Builder
-      # We allow this step to fail because if our image already has
-      # the workaround in place this will fail.
-      - name: Xcode 26 Beta 17A5241e Metal Workaround
-        continue-on-error: true
-        run: |
-          xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MyMetalExport/
-          sed -i '' -e 's/17A5241c/17A5241e/g' /tmp/MyMetalExport/MetalToolchain-17A5241c.exportedBundle/ExportMetadata.plist
-          xcodebuild -importComponent metalToolchain -importPath /tmp/MyMetalExport/MetalToolchain-17A5241c.exportedBundle
-
       - name: get the Zig deps
         id: deps
         run: nix build -L .#deps && echo "deps=$(readlink ./result)" >> $GITHUB_OUTPUT
@@ -377,7 +407,7 @@ jobs:
           authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
 
       - name: Xcode Select
-        run: sudo xcode-select -s /Applications/Xcode_16.4.app
+        run: sudo xcode-select -s /Applications/Xcode_26.0.app
 
       - name: get the Zig deps
         id: deps
@@ -695,7 +725,7 @@ jobs:
           authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
 
       - name: Xcode Select
-        run: sudo xcode-select -s /Applications/Xcode_16.4.app
+        run: sudo xcode-select -s /Applications/Xcode_26.0.app
 
       - name: get the Zig deps
         id: deps