diff --git a/conf/mentat-hawat.py.conf b/conf/mentat-hawat.py.conf
index e60fbf301091345e3322881b0a20f95da1060d13..0742a81331484d5356b7d23972bb3c67005a6fdc 100644
--- a/conf/mentat-hawat.py.conf
+++ b/conf/mentat-hawat.py.conf
@@ -1,6 +1,9 @@
 # Force enable the debug mode.
 #DEBUG = True
 
+# Debug template file loading precedence.
+#EXPLAIN_TEMPLATE_LOADING = True
+
 # Move the application from webserver root to different location.
 #APPLICATION_ROOT = '/mentat'
 
diff --git a/lib/vial/config.py b/lib/vial/config.py
index 16185b77d3665edc246803c0f98a519f5c67c984..90118649195f02ae54de95a79f2747f6170575e7 100644
--- a/lib/vial/config.py
+++ b/lib/vial/config.py
@@ -156,6 +156,10 @@ class DevelopmentConfig(Config):  # pylint: disable=locally-disabled,too-few-pub
     DEBUG = True
     """Overwrite default :py:const:`vial.config.Config.DEBUG`."""
 
+
+    EXPLAIN_TEMPLATE_LOADING = True
+    """Debug template file loading precedence."""
+
     #---------------------------------------------------------------------------
     # Custom application configurations.
     #---------------------------------------------------------------------------