diff --git a/.github/actions/pip-list/action.yml b/.github/actions/pip-list/action.yml
index 156fde4f..e567b3d7 100644
--- a/.github/actions/pip-list/action.yml
+++ b/.github/actions/pip-list/action.yml
@@ -20,9 +20,9 @@ runs:
         echo '<summary>pip list</summary>' >> $GITHUB_STEP_SUMMARY
         echo '' >> $GITHUB_STEP_SUMMARY
         echo '```' >> $GITHUB_STEP_SUMMARY
-        pip list >> $GITHUB_STEP_SUMMARY
+        uv pip list >> $GITHUB_STEP_SUMMARY
         echo '```' >> $GITHUB_STEP_SUMMARY
         echo '' >> $GITHUB_STEP_SUMMARY
         echo '</details>' >> $GITHUB_STEP_SUMMARY
-        pip list  # also print to stdout
+        uv pip list  # also print to stdout
       shell: bash
diff --git a/.github/actions/pkg-install/action.yml b/.github/actions/pkg-install/action.yml
index c1bbf361..b34c9c8d 100644
--- a/.github/actions/pkg-install/action.yml
+++ b/.github/actions/pkg-install/action.yml
@@ -40,7 +40,7 @@ runs:
 
     - name: Install package (archive)
       if: ${{ inputs.install-from == 'archive' }}
-      working-directory: pypi/
+      working-directory: ${{ inputs.pkg-folder }}
       run: |
         set -ex
         pip install '${{ env.PKG_SOURCE }}${{ inputs.pkg-extras }}' \
diff --git a/.github/workflows/check-docs.yml b/.github/workflows/check-docs.yml
index 91e18da6..ab9c7bf7 100644
--- a/.github/workflows/check-docs.yml
+++ b/.github/workflows/check-docs.yml
@@ -55,6 +55,7 @@ defaults:
 env:
   # just use CPU version since running on CPU machine
   TORCH_URL: "https://download.pytorch.org/whl/cpu/torch_stable.html"
+  UV_TORCH_BACKEND: cpu
   # default 0 means to keep for the maximum time
   KEEP_DAYS: 0
 
@@ -72,11 +73,12 @@ jobs:
         with:
           submodules: recursive
 
-      - name: Set up Python 🐍 ${{ inputs.python-version }}
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍 ${{ inputs.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ inputs.python-version }}
-          cache: "pip"
+          enable-cache: true
 
       - name: Install pandoc & texlive
         if: ${{ inputs.install-tex == 'true' }}
@@ -92,9 +94,9 @@ jobs:
       - name: Install dependencies
         timeout-minutes: 20
         run: |
-          pip --version
-          pip install -e . -U -r ${{ inputs.requirements-file }} -f ${TORCH_URL}
-          pip list
+          uv --version
+          uv pip install -e . -U -r ${{ inputs.requirements-file }} -f ${TORCH_URL}
+          uv pip list
 
       - name: Pull reusable 🤖 actions️
         if: ${{ inputs.actions-ref != '' }}
@@ -123,3 +125,6 @@ jobs:
           path: ${{ inputs.docs-dir }}/build/
           retention-days: ${{ env.KEEP_DAYS }}
           include-hidden-files: true
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
diff --git a/.github/workflows/check-package.yml b/.github/workflows/check-package.yml
index 4b910138..907b2d06 100644
--- a/.github/workflows/check-package.yml
+++ b/.github/workflows/check-package.yml
@@ -80,10 +80,12 @@ jobs:
         with:
           fetch-depth: 0 # checkout entire history for all branches (required when using scm-based versioning)
           submodules: recursive
-      - name: Set up Python 🐍
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ matrix.python-version || '3.x' }}
+          enable-cache: true
 
       - name: Pull reusable 🤖 actions️
         uses: actions/checkout@v5
@@ -93,8 +95,8 @@ jobs:
           repository: Lightning-AI/utilities
       - name: Prepare build env.
         run: |
-          pip install -q -r ./.cicd/requirements/gha-package.txt
-          pip list
+          uv pip install -q -r ./.cicd/requirements/gha-package.txt
+          uv pip list
       - name: Create package 📦
         uses: ./.cicd/.github/actions/pkg-create
       - name: Upload 📤 packages
@@ -104,6 +106,9 @@ jobs:
           name: ${{ inputs.artifact-name }}-build-${{ strategy.job-index }}
           path: dist
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   merge-artifacts:
     needs: pkg-build
     runs-on: ubuntu-latest
@@ -114,10 +119,16 @@ jobs:
           ref: ${{ inputs.actions-ref }}
           path: .cicd
           repository: Lightning-AI/utilities
+      - name: Set up uv and Python
+        uses: astral-sh/setup-uv@v7
+        with:
+          activate-environment: true
+          python-version: "3.10"
+          enable-cache: true
       - name: Prepare build env.
         run: |
-          pip install -q -r ./.cicd/requirements/gha-package.txt
-          pip list
+          uv pip install -q -r ./.cicd/requirements/gha-package.txt
+          uv pip list
 
       - name: Download 📥
         uses: actions/download-artifact@v6
@@ -136,6 +147,9 @@ jobs:
           name: ${{ inputs.artifact-name }}
           path: dist
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   pkg-check:
     needs: merge-artifacts
     runs-on: ${{ matrix.os }}
@@ -148,6 +162,7 @@ jobs:
         uses: actions/checkout@v5
         with:
           submodules: recursive
+      # NOTE: use pip as gold standard for package validation
       - name: Set up Python 🐍 ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with:
diff --git a/.github/workflows/check-precommit.yml b/.github/workflows/check-precommit.yml
index c4115f21..a9bb02d2 100644
--- a/.github/workflows/check-precommit.yml
+++ b/.github/workflows/check-precommit.yml
@@ -38,10 +38,12 @@ jobs:
           submodules: recursive
           token: ${{ secrets.github-token || github.token }}
 
-      - name: Set up Python 🐍
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ inputs.python-version }}
+          enable-cache: true
 
       - name: Cache 💽 pre-commit
         if: ${{ inputs.use-cache == true }}
@@ -53,9 +55,12 @@ jobs:
       - name: Run pre-commit 🤖
         id: precommit
         run: |
-          pip install -q pre-commit
+          uv pip install -q pre-commit
           pre-commit run --all-files
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
       - name: Fixing Pull Request ↩️
         if: always() && inputs.push-fixes == true && steps.precommit.outcome == 'failure'
         uses: actions-js/push@v1.5
diff --git a/.github/workflows/check-schema.yml b/.github/workflows/check-schema.yml
index d950468b..b9408878 100644
--- a/.github/workflows/check-schema.yml
+++ b/.github/workflows/check-schema.yml
@@ -31,10 +31,12 @@ jobs:
         uses: actions/checkout@v5
         with:
           submodules: recursive
-      - name: Set up Python
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: "3.10"
+          enable-cache: true
 
       # if actions version is given install defined versions
       - name: "[optional] Pull reusable 🤖 actions"
@@ -48,15 +50,16 @@ jobs:
         if: inputs.actions-ref != ''
         timeout-minutes: 5
         run: |
-          pip install -r ./.cicd/requirements/gha-schema.txt
-          pip list | grep "check-jsonschema"
+          uv pip install -r ./.cicd/requirements/gha-schema.txt
+          uv pip list | grep "check-jsonschema"
+
       # otherwise fall back to using the latest
       - name: "[default] Install recommended dependencies"
         if: inputs.actions-ref == ''
         timeout-minutes: 5
         run: |
-          pip install -q check-jsonschema
-          pip list | grep "check-jsonschema"
+          uv pip install -q check-jsonschema
+          uv pip list | grep "check-jsonschema"
 
       - name: Scan repo
         id: folders
@@ -92,3 +95,6 @@ jobs:
             echo $f;
             check-jsonschema -v $f --schemafile "$SCHEMA_FILE" --regex-variant="nonunicode";
           done
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
diff --git a/.github/workflows/check-typing.yml b/.github/workflows/check-typing.yml
index ecd4d211..7334e3d1 100644
--- a/.github/workflows/check-typing.yml
+++ b/.github/workflows/check-typing.yml
@@ -31,24 +31,28 @@ defaults:
 jobs:
   mypy:
     runs-on: ubuntu-24.04
+    env:
+      UV_TORCH_BACKEND: cpu
     steps:
       - name: Checkout 🛎️
         uses: actions/checkout@v5
         with:
           submodules: recursive
 
-      - name: Set up Python 🐍 ${{ inputs.python-version }}
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍 ${{ inputs.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ inputs.python-version }}
+          enable-cache: true
 
       - name: Install dependencies
         timeout-minutes: 20
         run: |
           # don't use --upgrade to respect the version installed via setup.py
-          pip install -e '.[${{ inputs.extra-typing }}]' mypy \
+          uv pip install -e '.[${{ inputs.extra-typing }}]' mypy types-requests \
             --extra-index-url https://download.pytorch.org/whl/cpu/torch_stable.html
-          pip list
+          uv pip list
 
       - name: Pull reusable 🤖 actions️
         if: ${{ inputs.actions-ref != '' }}
@@ -94,3 +98,6 @@ jobs:
             | sed 's/\.py//g;  s|${SOURCE_DIR}||g;  s|\/__init__||g;  s|\/|\.|g' \
             | xargs -I {} echo '"{}",' \
           || true
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
diff --git a/.github/workflows/ci-cli.yml b/.github/workflows/ci-cli.yml
index 538bec54..a66ddccc 100644
--- a/.github/workflows/ci-cli.yml
+++ b/.github/workflows/ci-cli.yml
@@ -22,15 +22,17 @@ jobs:
     steps:
       - name: Checkout 🛎
         uses: actions/checkout@v5
-      - name: Set up Python 🐍 ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍 ${{ matrix.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ matrix.python-version }}
+          enable-cache: true
 
       - name: install package
         run: |
-          pip install -e '.[cli]'
-          pip list
+          uv pip install -e '.[cli]'
+          uv pip list
 
       - name: run CLI
         working-directory: ./requirements
@@ -40,6 +42,9 @@ jobs:
           python -m lightning_utilities.cli requirements set-oldest --req_files="cli.txt"
           python -m lightning_utilities.cli requirements set-oldest --req_files='["cli.txt", "docs.txt"]'
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   cli-guardian:
     runs-on: ubuntu-latest
     needs: test-cli
diff --git a/.github/workflows/ci-scripts.yml b/.github/workflows/ci-scripts.yml
index 2966b322..1f90e1b9 100644
--- a/.github/workflows/ci-scripts.yml
+++ b/.github/workflows/ci-scripts.yml
@@ -22,49 +22,58 @@ jobs:
     steps:
       - name: Checkout 🛎
         uses: actions/checkout@v5
-      - name: Set up Python 🐍 ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍 ${{ matrix.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ matrix.python-version }}
-          cache: "pip"
+          enable-cache: true
 
       - name: Install dependencies
         timeout-minutes: 5
         run: |
-          pip install -r requirements/_tests.txt
-          pip --version
-          pip list
+          uv pip install -r requirements/_tests.txt
+          uv --version
+          uv pip list
 
       - name: test Scripts
         working-directory: ./scripts
-        run: pytest . -v
+        run: uv run pytest . -v
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
 
   standalone-run:
     runs-on: "ubuntu-22.04"
     timeout-minutes: 20
     env:
       TORCH_URL: "https://download.pytorch.org/whl/cpu/torch_stable.html"
+      UV_TORCH_BACKEND: cpu
     steps:
       - name: Checkout 🛎
         uses: actions/checkout@v5
-      - name: Set up Python 🐍 ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍 ${{ matrix.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: "3.10"
-          cache: "pip"
+          enable-cache: true
       - name: Install dependencies
         timeout-minutes: 20
         run: |
           set -e
-          pip install -e ".[cli]" -U -r requirements/_tests.txt -f $TORCH_URL
-          pip --version
-          pip list
+          uv pip install -e ".[cli]" -U -r requirements/_tests.txt -f $TORCH_URL
+          uv --version
+          uv pip list
 
       - name: Run standalone script
         run: bash ./scripts/run_standalone_tests.sh "tests"
         env:
           COVERAGE_SOURCE: "lightning_utilities"
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   scripts-guardian:
     runs-on: ubuntu-latest
     needs: [test-scripts, standalone-run]
diff --git a/.github/workflows/ci-testing.yml b/.github/workflows/ci-testing.yml
index 46b139a2..354cc2f6 100644
--- a/.github/workflows/ci-testing.yml
+++ b/.github/workflows/ci-testing.yml
@@ -24,42 +24,40 @@ jobs:
     timeout-minutes: 35
     env:
       TORCH_URL: "https://download.pytorch.org/whl/cpu/torch_stable.html"
+      UV_TORCH_BACKEND: cpu
     steps:
       - name: Checkout 🛎
         uses: actions/checkout@v5
         with:
           submodules: recursive
-      - name: Set up Python 🐍 ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍 ${{ matrix.python-version }}
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: ${{ matrix.python-version }}
+          enable-cache: true
 
       - name: Set oldest dependencies
         if: matrix.requires == 'oldest'
         timeout-minutes: 20
         run: |
-          pip install -e '.[cli]'
+          uv pip install -e '.[cli]'
           python -m lightning_utilities.cli requirements set-oldest
 
-      - name: Complex 💽 caching
-        uses: ./.github/actions/cache
-        with:
-          python-version: ${{ matrix.python-version }}
-
       - name: Install dependencies
         timeout-minutes: 20
         run: |
           set -e
-          pip install -e ".[cli]" -U -r requirements/_tests.txt -f $TORCH_URL
-          pip --version
-          pip list
+          uv pip install -e ".[cli]" -U -r requirements/_tests.txt -f $TORCH_URL
+          uv --version
+          uv pip list
 
       - name: Print 🖨️ dependencies
         uses: ./.github/actions/pip-list
 
       - name: Unittests
         working-directory: ./tests
-        run: python -m pytest unittests --cov=lightning_utilities --durations=50 --timeout=120
+        run: uv run python -m pytest unittests --cov=lightning_utilities --durations=50 --timeout=120
 
       - name: Statistics
         working-directory: ./tests
@@ -80,7 +78,10 @@ jobs:
 
       - name: test CI scripts
         working-directory: ./tests
-        run: python -m pytest scripts --durations=50 --timeout=120
+        run: uv run python -m pytest scripts --durations=50 --timeout=120
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
 
   testing-guardian:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/cleanup-caches.yml b/.github/workflows/cleanup-caches.yml
index b7be9101..de419340 100644
--- a/.github/workflows/cleanup-caches.yml
+++ b/.github/workflows/cleanup-caches.yml
@@ -41,6 +41,13 @@ jobs:
       - name: Checkout Code
         uses: actions/checkout@v5
 
+      - name: Set up uv and Python
+        uses: astral-sh/setup-uv@v7
+        with:
+          activate-environment: true
+          python-version: "3.10"
+          enable-cache: true
+
       - name: Pull reusable 🤖 actions️
         uses: actions/checkout@v5
         with:
@@ -49,7 +56,7 @@ jobs:
           repository: Lightning-AI/utilities
       - name: install requirements
         timeout-minutes: 20
-        run: pip install -U -r ./.cicd/.github/scripts/find-unused-caches.txt
+        run: uv pip install -U -r ./.cicd/.github/scripts/find-unused-caches.txt
 
       - name: List and Filer 🔍 caches
         run: |
@@ -66,3 +73,6 @@ jobs:
               # delete each cache based on file...
               gh api --method DELETE  -H "Accept: application/vnd.github+json" /repos/${{ github.repository }}/actions/caches/ $line;
           done < "unused-cashes.txt"
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
diff --git a/.github/workflows/cron-clear-cache.yml b/.github/workflows/cron-clear-cache.yml
index 61f1af82..41891440 100644
--- a/.github/workflows/cron-clear-cache.yml
+++ b/.github/workflows/cron-clear-cache.yml
@@ -29,6 +29,6 @@ jobs:
     with:
       scripts-ref: ${{ github.sha }} # use local version
       dry-run: ${{ github.event_name == 'pull_request' }}
-      # ise input if set of default...
+      # use input if set, otherwise default...
       pattern: ${{ inputs.pattern || 'pip|conda' }}
-      age-days: ${{ fromJSON(inputs.age-days) || 2 }}
+      age-days: ${{ inputs.age-days || 7 }}
diff --git a/.github/workflows/deploy-docs.yml b/.github/workflows/deploy-docs.yml
index 25ce1210..dadf8ed1 100644
--- a/.github/workflows/deploy-docs.yml
+++ b/.github/workflows/deploy-docs.yml
@@ -15,6 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     env:
       TORCH_URL: "https://download.pytorch.org/whl/cpu/torch_stable.html"
+      UV_TORCH_BACKEND: cpu
     steps:
       - name: Checkout 🛎️
         uses: actions/checkout@v5
@@ -22,20 +23,12 @@ jobs:
         with:
           persist-credentials: false
           submodules: recursive
-      - name: Set up Python 🐍
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: "3.10"
-          cache: "pip"
-
-      # Note: This uses an internal pip API and may not always work
-      # https://github.com/actions/cache/blob/master/examples.md#multiple-oss-in-a-workflow
-      - name: Cache 💽 pip
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/pip
-          key: pip-${{ hashFiles('requirements/*.txt') }}
-          restore-keys: pip-
+          enable-cache: true
 
       #- name: Install texlive
       #  timeout-minutes: 20
@@ -48,9 +41,9 @@ jobs:
       - name: Install dependencies
         timeout-minutes: 20
         run: |
-          pip --version
-          pip install -e . -U -q -r requirements/_docs.txt -f ${TORCH_URL}
-          pip list
+          uv --version
+          uv pip install -e . -U -q -r requirements/_docs.txt -f ${TORCH_URL}
+          uv pip list
         shell: bash
 
       - name: Make Documentation
@@ -67,3 +60,6 @@ jobs:
           clean: true # Automatically remove deleted files from the deploy branch
           target-folder: docs # If you'd like to push the contents of the deployment folder into a specific directory
           single-commit: true # you'd prefer to have a single commit on the deployment branch instead of full history
+
+      - name: Minimize uv cache
+        run: uv cache prune --ci
diff --git a/.github/workflows/release-pypi.yml b/.github/workflows/release-pypi.yml
index 4d6866d0..307ae0a7 100644
--- a/.github/workflows/release-pypi.yml
+++ b/.github/workflows/release-pypi.yml
@@ -22,12 +22,14 @@ jobs:
     steps:
       - name: Checkout 🛎️
         uses: actions/checkout@v5
-      - name: Set up Python 🐍
-        uses: actions/setup-python@v6
+      - name: Set up uv and Python 🐍
+        uses: astral-sh/setup-uv@v7
         with:
+          activate-environment: true
           python-version: "3.10"
+          enable-cache: true
       - name: Prepare build env.
-        run: pip install -r ./requirements/gha-package.txt
+        run: uv pip install -r ./requirements/gha-package.txt
       - name: Create 📦 package
         uses: ./.github/actions/pkg-create
       - name: Upload 📤 packages
@@ -36,6 +38,9 @@ jobs:
           name: pypi-packages-${{ github.sha }}
           path: dist
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   upload-package:
     needs: build-package
     if: github.event_name == 'release'
diff --git a/tests/unittests/cli/test_command_line.py b/tests/unittests/cli/test_command_line.py
index a379adf5..a4ff42a7 100644
--- a/tests/unittests/cli/test_command_line.py
+++ b/tests/unittests/cli/test_command_line.py
@@ -1,4 +1,5 @@
 import subprocess
+import sys
 from pathlib import Path
 
 import pytest
@@ -6,7 +7,7 @@
 
 def test_version():
     """Prints the help message for the requirements commands."""
-    return_code = subprocess.call(["python", "-mlightning_utilities.cli", "version"])  # noqa: S607
+    return_code = subprocess.call([sys.executable, "-m", "lightning_utilities.cli", "version"])  # noqa: S603
     assert return_code == 0
 
 
@@ -14,7 +15,7 @@ def test_version():
 class TestRequirements:
     """Test requirements commands."""
 
-    BASE_CMD = ("python", "-m", "lightning_utilities.cli", "requirements")
+    BASE_CMD = (sys.executable, "-m", "lightning_utilities.cli", "requirements")
     REQUIREMENTS_SAMPLE = """
 # This is sample requirements file
 #  with multi line comments