diff --git a/src/Binding/Loader/FilesystemDefinitions.php b/src/Binding/Loader/FilesystemDefinitions.php
index 504ff665dec60e154316890ad26b761935da6e20..f86c22e5848685a0e272faa9d207a10fc09b59f5 100644
--- a/src/Binding/Loader/FilesystemDefinitions.php
+++ b/src/Binding/Loader/FilesystemDefinitions.php
@@ -34,7 +34,7 @@ class FilesystemDefinitions implements BindingDefinitions {
 		}
 	}
 
-	private function load_from_file( Path $filename ) {
+	private function load_from_file( Path $filename ): iterable {
 		if ( ! $filename->is_file() ) {
 			return;
 		}