diff --git a/composer.json b/composer.json
index 6125f32..3928626 100644
--- a/composer.json
+++ b/composer.json
@@ -2,7 +2,7 @@
     "name": "ed-itsolutions/wp_enqueue_less",
     "description": "Enqueue Less stylesheets in your WordPress code. ",
     "require": {
-        "wikimedia/less.php": "^3.1"
+        "wikimedia/less.php": "^5.0"
     },
     "license": "MIT",
     "authors": [
diff --git a/wp_enqueue_less.php b/wp_enqueue_less.php
index df67cf8..05f3732 100644
--- a/wp_enqueue_less.php
+++ b/wp_enqueue_less.php
@@ -59,7 +59,7 @@ function wp_enqueue_less($key, $file, $variables){
     $details->hash = $hash;
     
     $details->fileHashes = array();
-    foreach($parser->allParsedFiles() as $fileName){
+    foreach($parser->getParsedFiles() as $fileName){
       $details->fileHashes[$fileName] = md5_file($fileName);
     }
 
@@ -90,4 +90,4 @@ function wp_enqueue_less($key, $file, $variables){
       }
     }
   });
-}
\ No newline at end of file
+}