prrao87 · Nov 5, 2026 · Nov 5, 2026 · Nov 5, 2026 · Nov 5, 2026
diff --git a/.github/workflows/python-publish.yml b/.github/workflows/python-publish.yml
@@ -1,5 +1,5 @@
-# Build, test and publish lance-csr wheels: Linux x86-64 (manylinux_2_28) and native
-# Apple Silicon (macOS arm64), plus an sdist for every other platform.
+# Build, test and publish lance-csr wheels: Linux x86-64 (manylinux_2_28), native
+# Apple Silicon (macOS arm64) and Windows x86-64, plus an sdist for every other platform.
 #
 # Pull requests that change how wheels are built (this workflow, the wheel check, the
 # release build profile) build and test them without publishing. A release builds and tests
@@ -135,15 +135,53 @@ jobs:
           path: python/dist/*.whl
           if-no-files-found: error
 
+  build-windows:
+    runs-on: windows-2022
+    timeout-minutes: 90
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - uses: astral-sh/setup-uv@v4
+
+      - name: Install build dependencies
+        run: choco install protoc --version=29.3 -y --no-progress
+
+      - name: Build Windows x86-64 wheel
+        uses: PyO3/maturin-action@04ac600d27cdf7a9a280dadf7147097c42b757ad # v1
+        with:
+          command: build
+          working-directory: python
+          target: x86_64-pc-windows-msvc
+          # sccache's Windows server dropped the connection mid-way through compiling lance.
+          sccache: "false"
+          args: --release --locked --strip --out dist
+
+      - name: Inspect wheel
+        working-directory: python
+        shell: bash
+        run: |
+          uvx twine check dist/*.whl
+          sha256sum dist/*.whl
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: python-dist-windows-x64
+          path: python/dist/*.whl
+          if-no-files-found: error
+
   test:
     # The wheels are abi3 (CPython 3.12+), so each platform's single wheel is tested on
     # every supported Python, in a clean environment with Rust removed from PATH: a wheel
     # that silently needed compiling would fail here.
-    needs: [build-linux, build-macos]
+    needs: [build-linux, build-macos, build-windows]
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-24.04, macos-15]
+        os: [ubuntu-24.04, macos-15, windows-2022]
         python: ["3.12", "3.13", "3.14"]
     runs-on: ${{ matrix.os }}
     timeout-minutes: 30
@@ -171,6 +209,7 @@ jobs:
           case "$RUNNER_OS" in
             Linux) wheel=$(ls "$PWD"/dist/*manylinux*.whl) ;;
             macOS) wheel=$(ls "$PWD"/dist/*macosx*.whl) ;;
+            Windows) wheel=$(cygpath -w "$(ls "$PWD"/dist/*win_amd64*.whl)") ;;
           esac
           # A fresh environment with the wheel and test tools; --no-build refuses any sdist.
           run=(uv run --isolated --no-project --no-build --python ${{ matrix.python }}
@@ -181,7 +220,7 @@ jobs:
           "${run[@]}" python -I -m pytest "$RUNNER_TEMP/tests" -q -p no:cacheprovider
 
   publish:
-    needs: [build-linux, build-macos, test]
+    needs: [build-linux, build-macos, build-windows, test]
     if: >
       github.event_name == 'release' ||
       (github.event_name == 'workflow_dispatch' && github.event.inputs.mode == 'release')

diff --git a/README.md b/README.md
@@ -58,7 +58,7 @@ case needs distributed graph queries or graph algorithms, that's the kind of eng
 uv add lance-csr
 ```
 
-Prebuilt wheels cover Linux x86-64 and native Apple Silicon (CPython 3.12+); no Rust toolchain is needed. From
+Prebuilt wheels cover Linux x86-64, native Apple Silicon and Windows x86-64 (CPython 3.12+); no Rust toolchain is needed. From
 Rust, run `cargo add lance-csr` and see the [Rust guide](https://lance-csr.hdclabs.ai/rust/). To build from
 source, see [`python/DEVELOPMENT.md`](python/DEVELOPMENT.md).
 

diff --git a/RELEASE.md b/RELEASE.md
@@ -4,7 +4,7 @@ A release publishes the Python package to [PyPI](https://pypi.org/project/lance-
 `lance-csr` crate to [crates.io](https://crates.io/crates/lance-csr). PyPI publishing is
 automated from a GitHub release, and the crates follow once PyPI has the new version.
 
-The whole release takes about 50 minutes: the macOS wheel build, then the crates. Don't add steps that build the
+The whole release takes about 65 minutes: the Windows wheel build, then the crates. Don't add steps that build the
 release wheels a second time.
 
 ## Before you start
@@ -66,6 +66,7 @@ Publishing it starts `.github/workflows/python-publish.yml`:
 | --- | ---: | --- |
 | `build-linux` | about 22 min | manylinux_2_28 x86-64 wheel and the sdist |
 | `build-macos` | about 35 min | macOS arm64 wheel, built natively on `macos-15` |
+| `build-windows` | about 52 min | Windows x86-64 wheel, built natively on `windows-2022` |
 | `test` | under 1 min each | each wheel on Python 3.12, 3.13 and 3.14 |
 | `publish` | seconds | checks the tag matches `python/pyproject.toml`, then uploads through PyPI trusted publishing |
 | `publish-crates` | about 10 to 15 min | after `publish`: packages and verifies `lance-csr`, then uploads it through crates.io trusted publishing |

diff --git a/python/.cargo/config.toml b/python/.cargo/config.toml
@@ -25,5 +25,8 @@ rustflags = [
 [target.x86_64-unknown-linux-gnu]
 rustflags = ["-C", "target-cpu=haswell", "-C", "target-feature=+avx2,+fma,+f16c"]
 
+[target.x86_64-pc-windows-msvc]
+rustflags = ["-C", "target-cpu=haswell", "-C", "target-feature=+avx2,+fma,+f16c"]
+
 [target.aarch64-apple-darwin]
 rustflags = ["-C", "target-cpu=apple-m1", "-C", "target-feature=+neon,+fp16"]
diff --git a/python/README.md b/python/README.md
@@ -18,8 +18,9 @@ Or run a script with it, without a project:
 uv run --with lance-csr python your_script.py
 ```
 
-Prebuilt wheels are published for Linux x86-64 (glibc 2.28 or newer: RHEL 8, Ubuntu 20.04 and later)
-and native Apple Silicon (macOS 11 or newer), for CPython 3.12 and later. Installing from a wheel needs
+Prebuilt wheels are published for Linux x86-64 (glibc 2.28 or newer: RHEL 8, Ubuntu 20.04 and later),
+native Apple Silicon (macOS 11 or newer) and Windows x86-64, for CPython 3.12 and later. The x86-64
+wheels need a CPU with AVX2 (Intel Haswell, AMD Excavator or newer). Installing from a wheel needs
 no Rust toolchain; to make sure uv never falls back to compiling from source, use:
 
 ```bash

diff --git a/python/pyproject.toml b/python/pyproject.toml
@@ -17,6 +17,7 @@ classifiers = [
     "Intended Audience :: Science/Research",
     "License :: OSI Approved :: Apache Software License",
     "Operating System :: MacOS",
+    "Operating System :: Microsoft :: Windows",
     "Operating System :: POSIX :: Linux",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",