diff --git a/.github/workflows/sphinx.yml b/.github/workflows/sphinx.yml
index 147aaf3..14b4404 100644
--- a/.github/workflows/sphinx.yml
+++ b/.github/workflows/sphinx.yml
@@ -38,7 +38,7 @@ jobs:
           path: .venv
           key: venv-${{ runner.os }}-${{ hashFiles('**/poetry.lock') }}
       - name: Install dependencies
-        run: poetry install
+        run: poetry install --no-root
         if: steps.cached-poetry-dependencies.outputs.cache-hit != 'true'
       - name: build docs
         run: make html