diff --git a/phpBB/phpbb/storage/adapter/local.php b/phpBB/phpbb/storage/adapter/local.php
index 4673dbca6e..dab6fbc34f 100644
--- a/phpBB/phpbb/storage/adapter/local.php
+++ b/phpBB/phpbb/storage/adapter/local.php
@@ -16,6 +16,9 @@ namespace phpbb\storage\adapter;
 use phpbb\storage\exception\exception;
 use phpbb\filesystem\exception\filesystem_exception;
 
+/**
+ * @internal Experimental
+ */
 class local implements adapter_interface
 {
 	/**
diff --git a/phpBB/phpbb/storage/storage.php b/phpBB/phpbb/storage/storage.php
index 1f5e751bbb..7f0ea4a6dc 100644
--- a/phpBB/phpbb/storage/storage.php
+++ b/phpBB/phpbb/storage/storage.php
@@ -13,6 +13,9 @@
 
 namespace phpbb\storage;
 
+/**
+ * @internal Experimental
+ */
 class storage
 {
 	protected $adapter;