diff --git a/apps/emqx_ft/src/emqx_ft_storage_fs.erl b/apps/emqx_ft/src/emqx_ft_storage_fs.erl
index 5754d2cfc..823407307 100644
--- a/apps/emqx_ft/src/emqx_ft_storage_fs.erl
+++ b/apps/emqx_ft/src/emqx_ft_storage_fs.erl
@@ -98,6 +98,7 @@
 }.
 
 -type storage() :: #{
+    type := 'local',
     segments := segments(),
     exporter := emqx_ft_storage_exporter:exporter()
 }.