diff --git a/.gitea/workflows/build.yml b/.gitea/workflows/build.yml
index 924b6b4..4e31792 100644
--- a/.gitea/workflows/build.yml
+++ b/.gitea/workflows/build.yml
@@ -22,7 +22,10 @@ jobs:
         run: npm ci || npm install
 
       - name: Install PyMuPDF (PDF text assertions)
-        run: python3 -m pip install --quiet pymupdf
+        run: |
+          python3 -m venv /tmp/venv
+          /tmp/venv/bin/pip install --quiet pymupdf
+          echo "/tmp/venv/bin" >> "$GITHUB_PATH"
 
       - name: Run tests
         run: npm test