diff --git a/src/Command/SyncCommand.php b/src/Command/SyncCommand.php
index 1056828..cb88c56 100644
--- a/src/Command/SyncCommand.php
+++ b/src/Command/SyncCommand.php
@@ -16,7 +16,7 @@ public function run(ArgumentValueList $arguments = null):void {
 			$pattern = $arguments->get("pattern");
 		}
 		catch(ArgumentValueListNotSetException) {
-			$pattern = null;
+			$pattern = "**/*";
 		}
 
 		$sync = new DirectorySync($source, $destination, $pattern);