diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 032a893..fa31252 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -1,5 +1,7 @@
 name: tests
 on: ['push', 'pull_request', 'workflow_call']
+env:
+  PYTHONHASHSEED: '0'
 jobs:
   tests:
     runs-on: ${{ matrix.os }}