diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 87e28d87f..8d8eb7f4a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -111,6 +111,8 @@ jobs:
             TEST_X86: 1
           - name: Windows (latest)
             os: windows-latest
+          - name: Windows arm64
+            os: windows-11-arm
           - name: Windows ClangCL (latest)
             os: windows-latest
             VS_GENERATOR_TOOLSET: ClangCL
@@ -172,6 +174,23 @@ jobs:
           make
           sudo make install
 
+      - name: Install rustup on Windows 11 ARM64 (until the image has it)
+        if: ${{ matrix.os == 'windows-11-arm' }}
+        shell: pwsh
+        run: |
+          Invoke-WebRequest -Uri "https://static.rust-lang.org/rustup/dist/aarch64-pc-windows-msvc/rustup-init.exe" -OutFile rustup-init.exe
+          .\rustup-init.exe --default-toolchain none -y
+          "$env:USERPROFILE\.cargo\bin" | Out-File -Append -Encoding ascii $env:GITHUB_PATH
+          "CARGO_HOME=$env:USERPROFILE\.cargo" | Out-File -Append -Encoding ascii $env:GITHUB_ENV
+          tree "$env:ProgramFiles\OpenSSL" /F
+
+      - name: Install rust on Windows 11 ARM64 (until the image has it)
+        if: ${{ matrix.os == 'windows-11-arm' }}
+        shell: pwsh
+        run: |
+          rustup install stable
+          rustup target add aarch64-pc-windows-msvc
+
       - name: Installing Linux GCC 9.4.0 Dependencies
         if: ${{ runner.os == 'Linux' && matrix.os == 'ubuntu-22.04' && !env['TEST_X86'] }}
         run: |
diff --git a/tests/requirements.txt b/tests/requirements.txt
index 50002c903..55a1fcd8f 100644
--- a/tests/requirements.txt
+++ b/tests/requirements.txt
@@ -3,6 +3,6 @@ pytest==8.1.1
 pytest-httpserver==1.0.10
 msgpack==1.0.8
 pytest-xdist==3.5.0
-clang-format==19.1.3
+clang-format==20.1.5
 pywin32==308; sys_platform == "win32"
 mitmproxy==11.0.0