chore(ci): switch Python dependency management in CI to uv

.github/workflows/ci-cloud.yml

@@ -48,25 +48,29 @@ jobs:
     env:
       TORCH_URL: "https://download.pytorch.org/whl/cpu/torch_stable.html"
       DISABLE_MPS: ${{ matrix.os == 'macOS-14' && '1' || '0' }}
+      UV_TORCH_BACKEND: "cpu"
 
     steps:
       - uses: actions/checkout@v5
-      - uses: actions/setup-python@v6
+
+      - name: Install uv and set Python ${{ matrix.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
           python-version: ${{ matrix.python-version }}
-          cache: "pip"
+          activate-environment: true
+          enable-cache: true
 
       - name: Set min. dependencies
         if: matrix.requires == 'oldest'
         run: |
-          pip install 'lightning-utilities[cli]'
+          uv pip install 'lightning-utilities[cli]'
           python -m lightning_utilities.cli requirements set-oldest --req_files='["requirements.txt"]'
 
       - name: Install package & dependencies
         run: |
-          pip --version
-          pip install -e '.[test,extra]' -U -q --find-links $TORCH_URL
-          pip list
+          uv --version
+          uv pip install -e '.[test,extra]' --find-links="${TORCH_URL}"
+          uv pip list
 
       - name: Test integrations
         env:
@@ -91,6 +95,9 @@ jobs:
           name: codecov-umbrella
           fail_ci_if_error: false
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   integration-guardian:
     runs-on: ubuntu-latest
     needs: integration

.github/workflows/ci-testing.yml

@@ -37,24 +37,27 @@ jobs:
     env:
       TORCH_URL: "https://download.pytorch.org/whl/cpu/torch_stable.html"
       DISABLE_MPS: ${{ matrix.os == 'macOS-14' && '1' || '0' }}
+      UV_TORCH_BACKEND: "cpu"
 
     steps:
       - uses: actions/checkout@v5
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+
+      - name: Install uv and set Python ${{ matrix.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
           python-version: ${{ matrix.python-version }}
-          cache: "pip"
+          activate-environment: true
+          enable-cache: true
 
       - name: Set min. dependencies
         if: matrix.requires == 'oldest'
         run: |
-          pip install 'lightning-utilities[cli]'
+          uv pip install 'lightning-utilities[cli]'
           python -m lightning_utilities.cli requirements set-oldest --req_files='["requirements.txt"]'
 
       - name: Adjust requirements
         run: |
-          pip install 'lightning-utilities[cli]' -U -q
+          uv pip install 'lightning-utilities[cli]' -q
           python -m lightning_utilities.cli requirements replace-pkg \
             --old_package="lightning" \
             --new_package="${{matrix.dependency}}" \
@@ -64,9 +67,9 @@ jobs:
       - name: Install package & dependencies
         run: |
           set -e
-          pip --version
-          pip install -e '.[test,extra]' -U -q --find-links $TORCH_URL
-          pip list
+          uv --version
+          uv pip install -e '.[test,extra]' --find-links="${TORCH_URL}"
+          uv pip list
           # check that right package was installed
           python -c "import ${{matrix.dependency}}; print(${{matrix.dependency}}.__version__)"
 
@@ -90,6 +93,9 @@ jobs:
           name: codecov-umbrella
           fail_ci_if_error: false
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   tests-guardian:
     runs-on: ubuntu-latest
     needs: pytester

.github/workflows/release-pypi.yml

@@ -4,6 +4,10 @@ name: PyPI Release
 on: # Trigger the workflow on push or pull request, but only for the main branch
   push:
     branches: [main]
+  pull_request:
+    branches: [main]
+    paths:
+      - ".github/workflows/release-pypi.yml"
   release:
     types: [published]
 
@@ -12,18 +16,27 @@ on: # Trigger the workflow on push or pull request, but only for the main branch
 jobs:
   build:
     runs-on: ubuntu-22.04
+
     steps:
-      - uses: actions/checkout@v5
-      - uses: actions/setup-python@v6
+      - uses: actions/checkout@v6
+
+      - name: Install uv and set Python 3.10
+        uses: astral-sh/setup-uv@v7
         with:
           python-version: "3.10"
+          activate-environment: true
+          enable-cache: true
 
       - name: Install dependencies
-        run: pip install -U -r _requirements/_ci.txt
+        run: |
+          uv pip install -U -r _requirements/_ci.txt
+          uv pip list
+
       - name: Build package
         run: python -m build
+
       - name: Check package
-        run: twine check dist/*
+        run: twine check dist/* --strict
 
       # We do this, since failures on test.pypi aren't that bad
       - name: Publish to Test PyPI