Add support for building aarch64 wheels (#182)

Co-authored-by: Shantanu <[email protected]>

.github/workflows/build.yml

@@ -13,7 +13,6 @@ jobs:
         # it also takes care of procuring the correct python version for us
         os: [ubuntu-latest, windows-latest, macos-latest]
         python-version: [36, 37, 38, 39, 310]
-
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
@@ -37,6 +36,43 @@ jobs:
         with:
           name: dist
           path: ./wheelhouse/*.whl
+  build_wheels_aarch64:
+    name: py${{ matrix.python-version }} on ${{ matrix.os }} (aarch64)
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        # cibuildwheel builds linux wheels inside a manylinux container
+        # it also takes care of procuring the correct python version for us
+        os: [ubuntu-latest]
+        python-version: [36, 37, 38, 39, 310]
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        name: Install Python
+        with:
+          python-version: "3.9"
+      - name: Setup up QEMU
+        uses: docker/setup-qemu-action@v1
+        with:
+          platforms: arm64
+      - name: Install cibuildwheel
+        run: |
+          python -m pip install "cibuildwheel==2.1.3"
+      - name: Build wheels
+        env:
+          CIBW_BUILD: "cp${{ matrix.python-version }}-*"
+          CIBW_ARCHS: aarch64
+          CIBW_BUILD_VERBOSITY: 1
+          CIBW_BEFORE_TEST: pip install pytest
+          CIBW_TEST_COMMAND: pytest {package}
+        run: |
+          python -m cibuildwheel --output-dir wheelhouse .
+      - uses: actions/upload-artifact@v2
+        with:
+          name: dist
+          path: ./wheelhouse/*.whl
   build_sdist_python_wheel:
     name: sdist and python wheel
     runs-on: ubuntu-latest