diff --git a/src/kernel/mconfig.ml b/src/kernel/mconfig.ml
index b269f8a05a..118ef02960 100644
--- a/src/kernel/mconfig.ml
+++ b/src/kernel/mconfig.ml
@@ -359,6 +359,14 @@ let merlin_flags = [
     marg_path (fun path merlin -> {merlin with stdlib = Some path}),
     "<path> Change path of ocaml standard library"
   );
+  (
+    "-cache-time",
+    Marg.param "int" (fun prot merlin ->
+        try {merlin with cache_flush = (int_of_string prot)}
+        with _ -> invalid_arg "Valid value is int";
+      ),
+    "Change file cache retention time"
+  );
   (
     (* Legacy support for janestreet. Ignored. To be removed soon. *)
     "-attributes-allowed",