Switch to uv build frontend and add top-level uv workspace

.gitattributes

@@ -14,6 +14,7 @@ cuda_core/cuda/core/_cpp/*.hpp -binary text diff
 *.svg binary
 # SCM syntax highlighting & preventing 3-way merges
 pixi.lock merge=binary linguist-language=YAML linguist-generated=true
+uv.lock merge=binary linguist-language=TOML linguist-generated=true
 
 # "export-subst" specifies that this file will get filled in with the current
 # commit and tag information when running `git archive`.  This allows

.github/workflows/build-docs.yml

@@ -1,4 +1,4 @@
-# SPDX-FileCopyrightText: Copyright (c) 2024-2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-FileCopyrightText: Copyright (c) 2024-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 #
 # SPDX-License-Identifier: Apache-2.0
 
@@ -77,6 +77,9 @@ jobs:
           conda config --show-sources
           conda config --show
 
+      - name: Install uv
+        uses: astral-sh/setup-uv@eac588ad8def6316056a12d4907a9d4d84ff7a3b  # v7.3.0
+
       # WAR: Building the doc currently requires CTK installed (NVIDIA/cuda-python#326,327)
       - name: Set up mini CTK
         uses: ./.github/actions/fetch_ctk
@@ -181,18 +184,18 @@ jobs:
       - name: Install all packages
         run: |
           pushd cuda_pathfinder
-          pip install *.whl
+          uv pip install --system *.whl
           popd
 
           pushd "${CUDA_BINDINGS_ARTIFACTS_DIR}"
-          pip install *.whl
+          uv pip install --system *.whl
           popd
 
           pushd "${CUDA_CORE_ARTIFACTS_DIR}"
-          pip install *.whl
+          uv pip install --system *.whl
           popd
 
-          pip install cuda_python*.whl
+          uv pip install --system cuda_python*.whl
 
       # This step sets the PR_NUMBER/BUILD_LATEST/BUILD_PREVIEW env vars.
       - name: Get PR number

.github/workflows/build-wheel.yml

@@ -106,15 +106,25 @@ jobs:
         run: |
           env
 
-      - name: Install twine
+      - name: Install uv
+        uses: astral-sh/setup-uv@eac588ad8def6316056a12d4907a9d4d84ff7a3b  # v7.3.0
+
+      # Shorten TEMP on Windows so cibuildwheel's build isolation paths
+      # stay within cmd.exe's ~8KB environment limit (needed for py3.14t).
+      - name: Shorten TEMP path (Windows)
+        if: ${{ startsWith(inputs.host-platform, 'win') }}
+        shell: pwsh
         run: |
-          pip install twine
+          $short = "C:\t"
+          New-Item -ItemType Directory -Force -Path $short | Out-Null
+          "TEMP=$short" | Out-File -FilePath $env:GITHUB_ENV -Append
+          "TMP=$short" | Out-File -FilePath $env:GITHUB_ENV -Append
 
       # To keep the build workflow simple, all matrix jobs will build a wheel for later use within this workflow.
       - name: Build and check cuda.pathfinder wheel
         run: |
           pushd cuda_pathfinder
-          pip wheel -v --no-deps .
+          uv build --wheel --out-dir dist
           popd
 
       - name: List the cuda.pathfinder artifacts directory
@@ -124,22 +134,22 @@ jobs:
           else
             export CHOWN="sudo chown"
           fi
-          $CHOWN -R $(whoami) cuda_pathfinder/*.whl
-          ls -lahR cuda_pathfinder
+          $CHOWN -R $(whoami) cuda_pathfinder/dist/*.whl
+          ls -lahR cuda_pathfinder/dist
 
       # We only need/want a single pure python wheel, pick linux-64 index 0.
       # This is what we will use for testing & releasing.
       - name: Check cuda.pathfinder wheel
         if: ${{ strategy.job-index == 0 && inputs.host-platform == 'linux-64' }}
         run: |
-          twine check --strict cuda_pathfinder/*.whl
+          uv tool run twine check --strict cuda_pathfinder/dist/*.whl
 
       - name: Upload cuda.pathfinder build artifacts
         if: ${{ strategy.job-index == 0 && inputs.host-platform == 'linux-64' }}
         uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f  # v6.0.0
         with:
           name: cuda-pathfinder-wheel
-          path: cuda_pathfinder/*.whl
+          path: cuda_pathfinder/dist/*.whl
           if-no-files-found: error
 
       - name: Set up mini CTK
@@ -192,9 +202,10 @@ jobs:
           $CHOWN -R $(whoami) ${{ env.CUDA_BINDINGS_ARTIFACTS_DIR }}
           ls -lahR ${{ env.CUDA_BINDINGS_ARTIFACTS_DIR }}
 
+
       - name: Check cuda.bindings wheel
         run: |
-          twine check --strict ${{ env.CUDA_BINDINGS_ARTIFACTS_DIR }}/*.whl
+          uv tool run twine check --strict ${{ env.CUDA_BINDINGS_ARTIFACTS_DIR }}/*.whl
 
       - name: Upload cuda.bindings build artifacts
         uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f  # v6.0.0
@@ -267,8 +278,7 @@ jobs:
         if: ${{ strategy.job-index == 0 && inputs.host-platform == 'linux-64' }}
         run: |
           pushd cuda_python
-          pip wheel -v --no-deps .
-          twine check --strict *.whl
+          uv build --wheel --out-dir dist
           popd
 
       - name: List the cuda-python artifacts directory
@@ -279,15 +289,20 @@ jobs:
           else
             export CHOWN="sudo chown"
           fi
-          $CHOWN -R $(whoami) cuda_python/*.whl
-          ls -lahR cuda_python
+          $CHOWN -R $(whoami) cuda_python/dist/*.whl
+          ls -lahR cuda_python/dist
+
+      - name: Check cuda-python wheel
+        if: ${{ strategy.job-index == 0 && inputs.host-platform == 'linux-64' }}
+        run: |
+          uv tool run twine check --strict cuda_python/dist/*.whl
 
       - name: Upload cuda-python build artifacts
         if: ${{ strategy.job-index == 0 && inputs.host-platform == 'linux-64' }}
         uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f  # v6.0.0
         with:
           name: cuda-python-wheel
-          path: cuda_python/*.whl
+          path: cuda_python/dist/*.whl
           if-no-files-found: error
 
       - name: Set up Python
@@ -310,13 +325,20 @@ jobs:
           # For caching
           echo "PY_EXT_SUFFIX=$(python -c "import sysconfig; print(sysconfig.get_config_var('EXT_SUFFIX'))")" >> $GITHUB_ENV
 
-      - name: Install cuda.pathfinder (required for next step)
-        run: |
-          pip install cuda_pathfinder/*.whl
+      # Create a fresh venv for the matrix Python (differs from the 3.12 used
+      # during the build phase above).
+      - name: Create venv
+        run: uv venv
 
       - name: Build cuda.bindings Cython tests
         run: |
-          pip install ${{ env.CUDA_BINDINGS_ARTIFACTS_DIR }}/*.whl --group ./cuda_bindings/pyproject.toml:test
+          # Install test deps first, then wheels (uv sync manages the env
+          # and would remove previously-installed wheels).
+          uv sync --frozen --package cuda-bindings --only-group test --no-install-project
+          uv pip install cuda_pathfinder/dist/*.whl
+          uv pip install ${{ env.CUDA_BINDINGS_ARTIFACTS_DIR }}/*.whl
+          # Activate venv so cythonize is on PATH for build_tests.sh
+          export PATH="${GITHUB_WORKSPACE}/.venv/bin:${GITHUB_WORKSPACE}/.venv/Scripts:${PATH}"
           pushd ${{ env.CUDA_BINDINGS_CYTHON_TESTS_DIR }}
           bash build_tests.sh
           popd
@@ -330,7 +352,11 @@ jobs:
 
       - name: Build cuda.core Cython tests
         run: |
-          pip install ${{ env.CUDA_CORE_ARTIFACTS_DIR }}/"cu${BUILD_CUDA_MAJOR}"/*.whl --group ./cuda_core/pyproject.toml:test
+          # Install test deps first, then the wheel.
+          uv sync --frozen --package cuda-core --only-group test --no-install-project
+          uv pip install ${{ env.CUDA_CORE_ARTIFACTS_DIR }}/"cu${BUILD_CUDA_MAJOR}"/*.whl
+          # Activate venv so cythonize is on PATH for build_tests.sh
+          export PATH="${GITHUB_WORKSPACE}/.venv/bin:${GITHUB_WORKSPACE}/.venv/Scripts:${PATH}"
           pushd ${{ env.CUDA_CORE_CYTHON_TESTS_DIR }}
           bash build_tests.sh
           popd
@@ -444,15 +470,15 @@ jobs:
 
       - name: Merge cuda.core wheels
         run: |
-          pip install wheel
+          uv pip install wheel
           python ci/tools/merge_cuda_core_wheels.py \
             "${{ env.CUDA_CORE_ARTIFACTS_DIR }}"/cu"${BUILD_CUDA_MAJOR}"/cuda_core*.whl \
             "${{ env.CUDA_CORE_ARTIFACTS_DIR }}"/cu"${BUILD_PREV_CUDA_MAJOR}"/cuda_core*.whl \
             --output-dir "${{ env.CUDA_CORE_ARTIFACTS_DIR }}"
 
       - name: Check cuda.core wheel
         run: |
-          twine check --strict ${{ env.CUDA_CORE_ARTIFACTS_DIR }}/*.whl
+          uv tool run twine check --strict ${{ env.CUDA_CORE_ARTIFACTS_DIR }}/*.whl
 
       - name: Upload cuda.core build artifacts
         uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f  # v6.0.0

.github/workflows/coverage.yml

@@ -1,4 +1,4 @@
-# SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 #
 # SPDX-License-Identifier: Apache-2.0
 
@@ -82,6 +82,11 @@ jobs:
           # we use self-hosted runners on which setup-python behaves weirdly...
           AGENT_TOOLSDIRECTORY: "/opt/hostedtoolcache"
 
+      - name: Install uv
+        uses: astral-sh/setup-uv@eac588ad8def6316056a12d4907a9d4d84ff7a3b  # v7.3.0
+        with:
+          activate-environment: true
+
       - name: Set up mini CTK
         if: ${{ env.LOCAL_CTK == '1' }}
         uses: ./.github/actions/fetch_ctk
@@ -90,57 +95,53 @@ jobs:
           host-platform: ${{ env.HOST_PLATFORM }}
           cuda-version: ${{ env.CUDA_VER }}
 
-      - name: Create venv
-        run: |
-          python -m venv .venv
-
       - name: Build cuda-pathfinder
         run: |
-          .venv/bin/pip install -v ./cuda_pathfinder
+          uv pip install -v ./cuda_pathfinder
 
       - name: Build cuda-python-test-helpers
         run: |
-          .venv/bin/pip install -v ./cuda_python_test_helpers
+          uv pip install -v ./cuda_python_test_helpers
 
       - name: Build cuda-bindings
         run: |
-          cd cuda_bindings
-          ../.venv/bin/pip install -v . --group test
+          uv pip install -v ./cuda_bindings
+          uv sync --frozen --package cuda-bindings --only-group test --no-install-project
 
       - name: Build cuda-core
         run: |
-          cd cuda_core
-          ../.venv/bin/pip install -v . --group test
+          uv pip install -v ./cuda_core
+          uv sync --frozen --package cuda-core --only-group "test-cu$(cut -d. -f1 <<< $CUDA_VER)" --no-install-project
 
       - name: Install coverage tools
         run: |
-          .venv/bin/pip install coverage pytest-cov
+          uv pip install coverage pytest-cov
 
       - name: Set cuda package install root
         run: |
-          echo "INSTALL_ROOT=$(.venv/bin/python -c 'import cuda; print(cuda.__path__[0])')/.." >> $GITHUB_ENV
+          echo "INSTALL_ROOT=$(python -c 'import cuda; print(cuda.__path__[0])')/.." >> $GITHUB_ENV
           echo "REPO_ROOT=$(pwd)" >> $GITHUB_ENV
 
       - name: Run cuda.pathfinder tests
         run: |
           cd $INSTALL_ROOT
-          $REPO_ROOT/.venv/bin/pytest -v --cov=./cuda --cov-append --cov-config=$REPO_ROOT/.coveragerc $REPO_ROOT/cuda_pathfinder/tests
+          pytest -v --cov=./cuda --cov-append --cov-config=$REPO_ROOT/.coveragerc $REPO_ROOT/cuda_pathfinder/tests
 
       - name: Run cuda.bindings tests
         run: |
           cd $INSTALL_ROOT
-          $REPO_ROOT/.venv/bin/pytest -v --cov=./cuda --cov-append --cov-config=$REPO_ROOT/.coveragerc $REPO_ROOT/cuda_bindings/tests
+          pytest -v --cov=./cuda --cov-append --cov-config=$REPO_ROOT/.coveragerc $REPO_ROOT/cuda_bindings/tests
 
       - name: Run cuda.core tests
         run: |
           cd $INSTALL_ROOT
-          $REPO_ROOT/.venv/bin/pytest -v --cov=./cuda --cov-append --cov-config=$REPO_ROOT/.coveragerc $REPO_ROOT/cuda_core/tests
+          pytest -v --cov=./cuda --cov-append --cov-config=$REPO_ROOT/.coveragerc $REPO_ROOT/cuda_core/tests
 
       - name: Generate coverage report
         run: |
           cd $INSTALL_ROOT
-          $REPO_ROOT/.venv/bin/coverage html --rcfile=$REPO_ROOT/.coveragerc
-          $REPO_ROOT/.venv/bin/coverage xml --rcfile=$REPO_ROOT/.coveragerc -o htmlcov/coverage.xml
+          coverage html --rcfile=$REPO_ROOT/.coveragerc
+          coverage xml --rcfile=$REPO_ROOT/.coveragerc -o htmlcov/coverage.xml
           mkdir $REPO_ROOT/docs
           mv htmlcov $REPO_ROOT/docs/coverage
 

.github/workflows/test-wheel-linux.yml

@@ -224,6 +224,11 @@ jobs:
           # we use self-hosted runners on which setup-python behaves weirdly (Python include can't be found)...
           AGENT_TOOLSDIRECTORY: "/opt/hostedtoolcache"
 
+      - name: Install uv
+        uses: astral-sh/setup-uv@eac588ad8def6316056a12d4907a9d4d84ff7a3b  # v7.3.0
+        with:
+          activate-environment: true
+
       - name: Set up mini CTK
         if: ${{ matrix.LOCAL_CTK == '1' }}
         uses: ./.github/actions/fetch_ctk
@@ -279,17 +284,19 @@ jobs:
       - name: Ensure cuda-python installable
         run: |
           if [[ "${{ matrix.LOCAL_CTK }}" == 1 ]]; then
-            pip install --only-binary=:all: cuda_python*.whl
+            uv pip install cuda_python*.whl
           else
-            pip install --only-binary=:all: $(ls cuda_python*.whl)[all]
+            uv pip install $(ls cuda_python*.whl)[all]
           fi
 
       - name: Install cuda.pathfinder extra wheels for testing
         run: |
           set -euo pipefail
           pushd cuda_pathfinder
-          pip install --only-binary=:all: -v ./*.whl --group "test-cu${TEST_CUDA_MAJOR}"
-          pip list
+          uv pip install -v ./*.whl
+          # Install the "test-cu${TEST_CUDA_MAJOR}" dependency group from cuda_pathfinder/pyproject.toml.
+          uv sync --frozen --package cuda-pathfinder --only-group "test-cu${TEST_CUDA_MAJOR}" --no-install-project
+          uv pip list
           popd
 
       - name: Run cuda.pathfinder tests with all_must_work

.github/workflows/test-wheel-windows.yml

@@ -208,6 +208,11 @@ jobs:
         with:
           python-version: ${{ matrix.PY_VER }}
 
+      - name: Install uv
+        uses: astral-sh/setup-uv@eac588ad8def6316056a12d4907a9d4d84ff7a3b  # v7.3.0
+        with:
+          activate-environment: true
+
       - name: Set up mini CTK
         if: ${{ matrix.LOCAL_CTK == '1' }}
         uses: ./.github/actions/fetch_ctk
@@ -254,19 +259,22 @@ jobs:
         run: run-tests core
 
       - name: Ensure cuda-python installable
+        shell: bash --noprofile --norc -xeuo pipefail {0}
         run: |
-          if ('${{ matrix.LOCAL_CTK }}' -eq '1') {
-            pip install --only-binary=:all: (Get-ChildItem -Filter cuda_python*.whl).FullName
-          } else {
-            pip install --only-binary=:all: "$((Get-ChildItem -Filter cuda_python*.whl).FullName)[all]"
-          }
+          if [[ "${{ matrix.LOCAL_CTK }}" == 1 ]]; then
+            uv pip install cuda_python*.whl
+          else
+            uv pip install $(ls cuda_python*.whl)[all]
+          fi
 
       - name: Install cuda.pathfinder extra wheels for testing
         shell: bash --noprofile --norc -xeuo pipefail {0}
         run: |
           pushd cuda_pathfinder
-          pip install --only-binary=:all: -v ./*.whl --group "test-cu${TEST_CUDA_MAJOR}"
-          pip list
+          uv pip install -v ./*.whl
+          # Install the "test-cu${TEST_CUDA_MAJOR}" dependency group from cuda_pathfinder/pyproject.toml.
+          uv sync --frozen --package cuda-pathfinder --only-group "test-cu${TEST_CUDA_MAJOR}" --no-install-project
+          uv pip list
           popd
 
       - name: Run cuda.pathfinder tests with all_must_work

.pre-commit-config.yaml

@@ -29,7 +29,7 @@ repos:
         language: python
         additional_dependencies:
           - https://files.pythonhosted.org/packages/cc/20/ff623b09d963f88bfde16306a54e12ee5ea43e9b597108672ff3a408aad6/pathspec-0.12.1-py3-none-any.whl
-        exclude: '(.*pixi\.lock)|(\.git_archival\.txt)'
+        exclude: '(.*pixi\.lock)|(\.git_archival\.txt)|uv\.lock'
         args: ["--fix"]
 
       - id: no-markdown-in-docs-source
@@ -46,7 +46,7 @@ repos:
     rev: "3e8a8703264a2f4a69428a0aa4dcb512790b2c8c"  # frozen: v6.0.0
     hooks:
     - id: check-added-large-files
-      exclude: cuda_bindings/cuda/bindings/nvml.pyx
+      exclude: 'cuda_bindings/cuda/bindings/nvml\.pyx|uv\.lock'
     - id: check-case-conflict
     - id: check-docstring-first
     - id: check-merge-conflict