diff --git a/kitty_tests/shell_integration.py b/kitty_tests/shell_integration.py
index b0c803aa8..9d758e3e9 100644
--- a/kitty_tests/shell_integration.py
+++ b/kitty_tests/shell_integration.py
@@ -40,6 +40,7 @@ def basic_shell_env(home_dir):
         'KITTY_SHELL_INTEGRATION': 'enabled',
         'KITTY_INSTALLATION_DIR': kitty_base_dir,
         'BASH_SILENCE_DEPRECATION_WARNING': '1',
+        'PYTHONDONTWRITEBYTECODE': '1',
     }
     for x in ('USER', 'LANG'):
         if os.environ.get(x):