Base the CFP text on a closing date instead of a

...boolean

app/config/sculpin_site.yml

@@ -9,4 +9,4 @@ subtitle: A conference about the Sculpin static site generator.
 #    shortname:
 
 cfp:
-    open: true
+    close_date: 2025-01-01

source/index.html.twig

@@ -4,7 +4,8 @@ title: Welcome to SculpinCon!
 
 <h1>{{ page.title }}</h1>
 
-{% if site.cfp.open %}
+{# Show the "submit to our CFP" text if the current date is before the closing date. #}
+{% if 'today'|date('U') < site.cfp.close_date %}
   <p>Please submit to our call for papers!</p>
 {% else %}
   <p>Our call for papers is now closed.</p>