diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 8f8bbd2..3c8b3ec 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -50,6 +50,11 @@ jobs:
       with:
         python-version: "${{ env.PYTHON_VERSION }}"
 
+    - uses: actions/cache@v3
+      with:
+        path: __pypackages__
+        key: ${{ runner.os }}-pypackages-${{ hashFiles('pdm.lock') }}
+
     - name: "Install: Python dependencies"
       run: |
         set -eux