diff --git a/.github/workflows/unittest.yml b/.github/workflows/unittest.yml
index d4350c8..6613e9e 100644
--- a/.github/workflows/unittest.yml
+++ b/.github/workflows/unittest.yml
@@ -13,18 +13,22 @@ jobs:
   pep8:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
-    - name: Set up Python 3.12
-      uses: actions/setup-python@v5
+    - name: Check out repository
+      uses: actions/checkout@v4
       with:
-        python-version: 3.12
-    - name: Install Python dependencies
-      run: |
-        python -m pip install poetry
-        poetry install --sync --with dev
-    - name: Lint with flake8
-      run: |
-        poetry run flake8 . --count
+        ref: ${{ github.head_ref }}
+        fetch-depth: 0
+    - name: autopep8
+      id: autopep8
+      uses: j-z10/autopep8@669deac37f8d1de9629679e31ba700a35eebd042
+      with:
+        args: --exit-code --recursive --in-place .
+    - name: Fail if autopep8 detected issues
+      if: steps.autopep8.outputs.exit-code == 2
+      uses: actions/github-script@v7
+      with: 
+        script: |
+          core.setFailed('Code style issues found.')
 
   test:
     needs: pep8