From 13750f0505a7068f0b784e93f4200bf734232cec Mon Sep 17 00:00:00 2001
From: Matthew Douglas <38992547+matthewdouglas@users.noreply.github.com>
Date: Fri, 29 May 2026 15:58:27 -0400
Subject: [PATCH 1/2] ci: add windows arm64 CPU to nightly CI

---
 .github/workflows/test-runner.yml   | 15 ++++++++++++---
 .github/workflows/tests-nightly.yml | 11 ++++++++++-
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/test-runner.yml b/.github/workflows/test-runner.yml
index 7750646c1..f06bdf815 100644
--- a/.github/workflows/test-runner.yml
+++ b/.github/workflows/test-runner.yml
@@ -112,6 +112,11 @@ jobs:
                 TEST_RUNNER="windows-2025"
               fi
               ;;
+            windows-arm64)
+              BUILD_OS="windows-11-arm"
+              ARCH="arm64"
+              TEST_RUNNER="windows-11-arm"
+              ;;
             *)
               echo "::error::Unsupported platform: ${{ inputs.platform }}"
               exit 1
@@ -152,8 +157,10 @@ jobs:
 
       # Windows: Setup MSVC (needed for both CPU and CUDA builds)
       - name: Setup MSVC
-        if: inputs.platform == 'windows'
+        if: startsWith(inputs.platform, 'windows')
         uses: ilammy/msvc-dev-cmd@v1.13.0
+        with:
+          arch: ${{ inputs.platform == 'windows-arm64' && 'arm64' || 'x64' }}
 
       # Build CPU backend
       - name: Build C++
@@ -198,12 +205,14 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.10'
+          python-version: ${{ inputs.platform == 'windows-arm64' && '3.12' || '3.10' }}
 
       # Windows: Setup MSVC for torch.compile
       - name: Setup MSVC
-        if: inputs.platform == 'windows'
+        if: startsWith(inputs.platform, 'windows')
         uses: ilammy/msvc-dev-cmd@v1.13.0
+        with:
+          arch: ${{ inputs.platform == 'windows-arm64' && 'arm64' || 'x64' }}
 
       - name: Install torch (nightly)
         if: inputs.torch_version == 'nightly'
diff --git a/.github/workflows/tests-nightly.yml b/.github/workflows/tests-nightly.yml
index db8a1d6d2..f13737026 100644
--- a/.github/workflows/tests-nightly.yml
+++ b/.github/workflows/tests-nightly.yml
@@ -17,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        platform: [linux-x64, linux-aarch64, macos, windows]
+        platform: [linux-x64, linux-aarch64, macos, windows, windows-arm64]
         # default runners don't have AVX-512 support, but icelake does
         cpu_type: ["", icelake]
         torch_version: ["2.4.1", "2.12.0", "nightly"]
@@ -33,12 +33,21 @@ jobs:
             cpu_type: icelake
           - platform: windows
             cpu_type: icelake
+          - platform: windows-arm64
+            cpu_type: icelake
+          # windows-arm64: torch >= 2.7.0 required (first version with official WoA wheels)
+          - platform: windows-arm64
+            torch_version: "2.4.1"
 
         include:
           # Add aarch64 with torch 2.5.1
           - platform: linux-aarch64
             cpu_type: ""
             torch_version: "2.5.1"
+          # Add windows-arm64 with minimum torch 2.7.1
+          - platform: windows-arm64
+            cpu_type: ""
+            torch_version: "2.7.1"
 
     uses: ./.github/workflows/test-runner.yml
     with:

From 515bc955ebf899c6dc22257b97a47237a4a2fbb3 Mon Sep 17 00:00:00 2001
From: Matthew Douglas <38992547+matthewdouglas@users.noreply.github.com>
Date: Mon, 1 Jun 2026 14:02:16 -0400
Subject: [PATCH 2/2] Tests: build WoA on arm64 runner properly

---
 .github/workflows/test-runner.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/test-runner.yml b/.github/workflows/test-runner.yml
index f06bdf815..53c57912d 100644
--- a/.github/workflows/test-runner.yml
+++ b/.github/workflows/test-runner.yml
@@ -42,6 +42,7 @@ jobs:
         inputs.platform == 'linux-x64' && 'ubuntu-22.04' ||
         inputs.platform == 'linux-aarch64' && 'ubuntu-22.04-arm' ||
         inputs.platform == 'macos' && 'macos-15' ||
+        inputs.platform == 'windows-arm64' && 'windows-11-arm' ||
         'windows-2025'
       }}
     outputs: