diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index f2fda55..19b3ebf 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -4,36 +4,149 @@ on:
   release:
     types: [created]
 
+  # Enable Run Workflow button in GitHub UI
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
-  wheels:
+  build_sdist:
+    name: Build SDist
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Build SDist
+        run: pipx run build --sdist
+
+      - name: Check metadata
+        run: pipx run twine check dist/*
+
+      - uses: actions/upload-artifact@v3
+        with:
+          path: dist/*.tar.gz
+
+
+  build_wheels:
+    name: Wheels on ${{ matrix.platform_id }} - ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
-    defaults:
-      run:
-        shell: bash -l {0}
     strategy:
       fail-fast: false
       matrix:
-        os: ["ubuntu-latest"]
+        # Loosely based on scikit-learn's config:
+        # https://github.com/scikit-learn/scikit-learn/blob/main/.github/workflows/wheels.yml
+        include:
+          - os: windows-latest
+            python-version: "3.8"
+            platform_id: win_amd64
+
+          - os: ubuntu-latest
+            python-version: "3.8"
+            platform_id: manylinux_x86_64
+            manylinux_image: manylinux2014
+          - os: ubuntu-latest
+            python-version: "3.8"
+            platform_id: manylinux_aarch64
+            manylinux_image: manylinux2014
+
+            # Use x86 macOS runner to build both x86 and ARM. GitHub does not offer M1/M2 yet (only self-hosted).
+          - os: macos-latest
+            python-version: "3.8"
+            platform_id: macosx_x86_64
+
     steps:
-    - name: Checkout
-      uses: actions/checkout@v3
-    - name: Set up Python
-      uses: actions/setup-python@v4
-      with:
-        python-version: '3.8'
-    - name: Upgrade pip
-      run: |
-        python -m pip install --upgrade pip
-    - name: Build manylinux Python wheels
-      uses: RalfG/python-wheels-manylinux-build@v0.4.2-manylinux2014_x86_64
-      with:
-        python-versions: 'cp38-cp38 cp39-cp39'
-        build-requirements: 'cffi numpy>=1.19,<1.20 cython'
-        pre-build-command: ${{ format('sh suitesparse.sh {0}', github.ref) }}
-    - name: Publish wheels to PyPI
-      env:
-        TWINE_USERNAME: __token__
-        TWINE_PASSWORD: ${{ secrets.PYPI_TOKEN }}
-      run: |
-        pip install twine
-        twine upload dist/*-manylinux*.whl
+      - uses: actions/checkout@v3
+
+      - uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install tools (macOS)
+        if: contains(matrix.os, 'macos')
+        # * install coreutils which includes `nproc` used by `make -j` in suitesparse.sh
+        # * GitHub actions comes with libomp already installed. It's listed here to explicitly list this requirement.
+        run: |
+          brew install coreutils
+          brew install libomp
+
+      - name: Build Wheels
+        env:
+          # very verbose
+          CIBW_BUILD_VERBOSITY: 3
+
+          # Build SuiteSparse
+          CIBW_BEFORE_ALL: bash suitesparse.sh ${{ github.ref }}
+#          CIBW_BEFORE_ALL: bash suitesparse.sh refs/tags/7.4.3.0
+
+          # Ask suitesparse.sh to build libraries in MSVC style on Windows.
+          CIBW_ENVIRONMENT_WINDOWS: CMAKE_GNUtoMS=ON
+
+          # macOS libomp setup.
+          # FindOpenMP doesn't find brew's libomp, so set the necessary configs manually.
+          # The OpenMP_* variables need to be passed to CMake as -D defines, that is done by suitesparse.sh
+          CIBW_ENVIRONMENT_MACOS: LDFLAGS="-L$(brew --prefix libomp)/lib" OpenMP_C_FLAGS="-Xclang -fopenmp -I$(brew --prefix libomp)/include" OpenMP_C_LIB_NAMES="libomp" OpenMP_libomp_LIBRARY="omp"
+
+          # Uncomment to only build CPython wheels
+          # CIBW_BUILD: "cp*"
+
+          # macOS: build x86_64 and arm64
+          CIBW_ARCHS_MACOS: "x86_64 arm64"
+
+          # No 32-bit builds
+          CIBW_SKIP: "*-win32 *_i686"
+
+          # Use delvewheel on Windows.
+          # This copies graphblas.dll into the wheel. "repair" in cibuildwheel parlance includes copying any shared
+          # libraries from the build host into the wheel to make the wheel self-contained.
+          # Cibuildwheel includes tools for this for Linux and macOS, and they recommend delvewheel for Windows.
+          CIBW_BEFORE_BUILD_WINDOWS: "pip install delvewheel"
+          CIBW_REPAIR_WHEEL_COMMAND_WINDOWS: "delvewheel repair --add-path \"C:\\Program Files (x86)\\bin\" --no-mangle \"libgomp-1.dll;libgcc_s_seh-1.dll\" -w {dest_dir} {wheel}"
+
+          # Test dependencies
+          CIBW_TEST_REQUIRES: "pytest"
+
+          # run tests
+          CIBW_TEST_COMMAND: "pytest {project}/suitesparse_graphblas/tests"
+
+          # GitHub Actions macOS Intel runner cannot run ARM tests.
+          CIBW_TEST_SKIP: "*-macosx_arm64"
+
+        run: |
+          python -m pip install cibuildwheel
+          python -m cibuildwheel --output-dir wheelhouse .
+        shell: bash
+
+      - uses: actions/upload-artifact@v3
+        with:
+          path: wheelhouse/*.whl
+
+
+  upload_all:
+    name: Upload to PyPI
+    needs: [build_wheels, build_sdist]
+    runs-on: ubuntu-latest
+#    if: github.event_name == 'release' && github.event.action == 'published'
+
+    steps:
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.x"
+
+      - uses: actions/download-artifact@v3
+        with:
+          name: artifact
+          path: dist
+
+      - uses: pypa/gh-action-pypi-publish@release/v1
+        with:
+          # PyPI does not allow replacing a file. Without this flag the entire action fails if even a single duplicate exists.
+          skip_existing: true
+          verbose: true
+          # Real PyPI:
+#          password: ${{ secrets.PYPI_TOKEN }}
+
+          # Test PyPI:
+          password: ${{ secrets.TEST_PYPI_API_TOKEN }}
+          repository_url: https://test.pypi.org/legacy/
diff --git a/suitesparse.sh b/suitesparse.sh
old mode 100644
new mode 100755
index 77410fc..119b96e
--- a/suitesparse.sh
+++ b/suitesparse.sh
@@ -1,14 +1,68 @@
+#!/bin/bash
 
+# parse SuiteSparse version from first argument, a git tag that ends in the version (no leading v)
 if [[ $1 =~ refs/tags/([0-9]*\.[0-9]*\.[0-9]*)\..*$ ]];
 then
     VERSION=${BASH_REMATCH[1]}
 else
+    echo "Specify a SuiteSparse version, such as: $0 refs/tags/7.4.3.0"
     exit -1
 fi
 echo VERSION: $VERSION
 
+NPROC="$(nproc)"
+if [ -z "${NPROC}" ]; then
+    # Default for platforms that don't have nproc. Mostly Windows.
+    NPROC="2"
+fi
+
+cmake_params=()
+if [ -n "${OpenMP_C_FLAGS}" ]; then
+    # macOS OpenMP flags.
+    # wheels.yml sets them as env vars, but CMake needs them as -D defs.
+    cmake_params+=(-DOpenMP_C_FLAGS="${OpenMP_C_FLAGS}")
+    cmake_params+=(-DOpenMP_C_LIB_NAMES="${OpenMP_C_LIB_NAMES}")
+    cmake_params+=(-DOpenMP_libomp_LIBRARY="${OpenMP_libomp_LIBRARY}")
+fi
+
+if [ -n "${CMAKE_GNUtoMS}" ]; then
+    # Windows needs .lib libraries, not .a
+    cmake_params+=(-DCMAKE_GNUtoMS=ON)
+    # Windows expects 'graphblas.lib', not 'libgraphblas.lib'
+    cmake_params+=(-DCMAKE_SHARED_LIBRARY_PREFIX=)
+    cmake_params+=(-DCMAKE_STATIC_LIBRARY_PREFIX=)
+fi
+
 curl -L https://github.com/DrTimothyAldenDavis/GraphBLAS/archive/refs/tags/v${VERSION}.tar.gz | tar xzf -
 cd GraphBLAS-${VERSION}/build
-cmake .. -DCMAKE_BUILD_TYPE=Release
-make -j$(nproc)
+
+# Disable optimizing some rarely-used types for significantly faster builds and significantly smaller wheel size.
+# Also the build with all types enabled sometimes stalls on GitHub Actions. Probably due to exceeded resource limits.
+# These can still be used, they'll just have reduced performance (AFAIK similar to UDTs).
+#echo "#define GxB_NO_BOOL      1" >> ../Source/GB_control.h #
+#echo "#define GxB_NO_FP32      1" >> ../Source/GB_control.h #
+#echo "#define GxB_NO_FP64      1" >> ../Source/GB_control.h #
+#echo "#define GxB_NO_FC32      1" >> ../Source/GB_control.h #
+#echo "#define GxB_NO_FC64      1" >> ../Source/GB_control.h #
+echo "#define GxB_NO_INT16     1" >> ../Source/GB_control.h
+echo "#define GxB_NO_INT32     1" >> ../Source/GB_control.h
+#echo "#define GxB_NO_INT64     1" >> ../Source/GB_control.h #
+echo "#define GxB_NO_INT8      1" >> ../Source/GB_control.h
+echo "#define GxB_NO_UINT16    1" >> ../Source/GB_control.h
+echo "#define GxB_NO_UINT32    1" >> ../Source/GB_control.h
+echo "#define GxB_NO_UINT64    1" >> ../Source/GB_control.h
+echo "#define GxB_NO_UINT8     1" >> ../Source/GB_control.h
+
+cmake .. -DCMAKE_BUILD_TYPE=Release -G 'Unix Makefiles' "${cmake_params[@]}"
+make -j$NPROC
 make install
+
+if [ -n "${CMAKE_GNUtoMS}" ]; then
+    # Windows:
+    # CMAKE_STATIC_LIBRARY_PREFIX is sometimes ignored, possibly when the MinGW toolchain is selected.
+    # Drop the 'lib' prefix manually.
+    echo "manually removing lib prefix"
+    mv "C:/Program Files (x86)/lib/libgraphblas.lib" "C:/Program Files (x86)/lib/graphblas.lib"
+    mv "C:/Program Files (x86)/lib/libgraphblas.dll.a" "C:/Program Files (x86)/lib/graphblas.dll.a"
+    cp "C:/Program Files (x86)/bin/libgraphblas.dll" "C:/Program Files (x86)/bin/graphblas.dll"
+fi
diff --git a/suitesparse_graphblas/tests/__init__.py b/suitesparse_graphblas/tests/__init__.py
deleted file mode 100644
index e69de29..0000000