diff --git a/src/bornhack/settings.py b/src/bornhack/settings.py
index da1e8781..0730de07 100644
--- a/src/bornhack/settings.py
+++ b/src/bornhack/settings.py
@@ -201,3 +201,6 @@ DATA_UPLOAD_MAX_NUMBER_FIELDS = 5000
 
 # use captcha form
 ACCOUNT_SIGNUP_FORM_CLASS = "bornhack.forms.AllAuthSignupCaptchaForm"
+
+# django 3.2 https://docs.djangoproject.com/en/3.2/releases/3.2/#customizing-type-of-auto-created-primary-keys
+DEFAULT_AUTO_FIELD = 'django.db.models.AutoField'