diff --git a/inc/instance-config.php b/inc/instance-config.php
index 0826e894..1701fc64 100644
--- a/inc/instance-config.php
+++ b/inc/instance-config.php
@@ -198,6 +198,8 @@ $config['spam']['unicode'] = false;
 $config['twig_cache'] = false;
 $config['report_captcha'] = true;
 
+$config['page_404'] = 'page_404';
+
 // 8chan specific mod pages
 require '8chan-mod-config.php';
 
@@ -206,4 +208,3 @@ require_once 'instance-functions.php';
 	
 // Load database credentials
 require "secrets.php";
-
diff --git a/inc/instance-functions.php b/inc/instance-functions.php
index 9bcc7c3f..71e933d1 100644
--- a/inc/instance-functions.php
+++ b/inc/instance-functions.php
@@ -18,3 +18,7 @@ function max_posts_per_hour($post) {
 		return ($r['count'] > $config['hour_max_threads']);
 	}
 }
+
+function page_404() {
+	include('404.php');
+}
diff --git a/smart_build.php b/smart_build.php
index da1966d0..ac016480 100644
--- a/smart_build.php
+++ b/smart_build.php
@@ -147,6 +147,9 @@ function die_404() { global $config;
     header("Status: 404 Not Found");
     echo "<h1>404 Not Found</h1><p>Page doesn't exist<hr><address>vichan</address>";
   }
+  elseif (is_callable($config['page_404'])) {
+    $config['page_404']();
+  }
   else {
     header("Location: ".$config['page_404']);
   }