diff --git a/src/NodeAvailabilityService.php b/src/NodeAvailabilityService.php
index 108f1849640d6a63abe0d8d53e70bff73d039785..ee7315748827ee53493a8bbe016a85b7703a57e1 100644
--- a/src/NodeAvailabilityService.php
+++ b/src/NodeAvailabilityService.php
@@ -43,7 +43,7 @@ class NodeAvailabilityService extends AbstractExtension {
    */
   public function getFunctions() {
     return [
-      new TwigFunction('node_availability', [$this, 'getNodeAvailability']),
+      new TwigFunction('node_availability', $this->getNodeAvailability(...)),
     ];
   }