diff --git a/roles/mailman3/templates/settings.py.j2 b/roles/mailman3/templates/settings.py.j2
index 7249269cb1..49cb1e26bd 100644
--- a/roles/mailman3/templates/settings.py.j2
+++ b/roles/mailman3/templates/settings.py.j2
@@ -13,7 +13,7 @@ from mailman_web.settings.mailman import *  # noqa: F403
 SECRET_KEY = '{{ mailman_hyperkitty_cookie_key }}'
 
 # SECURITY WARNING: don't run with debug turned on in production!
-{% if env = 'staging' %}
+{% if env == 'staging' %}
 DEBUG = True
 {% else %}
 DEBUG = False