diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
index 08339a2..5f63bb6 100644
--- a/.github/workflows/tests.yaml
+++ b/.github/workflows/tests.yaml
@@ -10,6 +10,9 @@ jobs:
       - name: Check out repository code
         uses: actions/checkout@v4
 
+      - name: Install poetry
+        run: pipx install poetry
+
       - name: Install maturin
         run: pipx install maturin
 
@@ -17,10 +20,10 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: '3.11'
-          cache: 'pip'
+          cache: 'poetry'
 
-      - run: maturin develop --release --all-features
-      - run: pytest -v
+      - run: poetry run maturin develop --release --all-features
+      - run: poetry run pytest -v
 
   mypy:
     runs-on: ubuntu-latest
@@ -30,6 +33,9 @@ jobs:
       - name: Check out repository code
         uses: actions/checkout@v4
 
+      - name: Install poetry
+        run: pipx install poetry
+
       - name: Install maturin
         run: pipx install maturin
 
@@ -37,7 +43,7 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: '3.11'
-          cache: 'pip'
+          cache: 'poetry'
 
-      - run: maturin develop --release --all-features
-      - run: mypy ./pyobs_cloudcover
\ No newline at end of file
+      - run: poetry run maturin develop --release --all-features
+      - run: poetry run mypy ./pyobs_cloudcover
\ No newline at end of file