diff --git a/.github/workflows/pythonpackage.yml b/.github/workflows/pythonpackage.yml
index e4dd945..28fa0f9 100644
--- a/.github/workflows/pythonpackage.yml
+++ b/.github/workflows/pythonpackage.yml
@@ -19,15 +19,15 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install .
+        pip install . -c constraints.txt
     - name: Lint with flake8
       run: |
-        pip install flake8
+        pip install flake8 -c constraints.txt
         # stop the build if there are Python syntax errors or undefined names
         flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
         # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
         flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
     - name: Test with pytest
       run: |
-        pip install pytest==8.2.2
+        pip install pytest==8.2.2 -c constraints.txt
         PYTHONPATH=. pytest
diff --git a/constraints.txt b/constraints.txt
new file mode 100644
index 0000000..1b1169c
--- /dev/null
+++ b/constraints.txt
@@ -0,0 +1,2 @@
+setuptools<=69
+