diff --git a/plugins/qcheck-stm/src/config.ml b/plugins/qcheck-stm/src/config.ml
index 36064d7b..c13ce218 100644
--- a/plugins/qcheck-stm/src/config.ml
+++ b/plugins/qcheck-stm/src/config.ml
@@ -221,7 +221,12 @@ let init gospel config_module =
   let open Reserr in
   try
     let module_name = Utils.module_name_of_path gospel
-    and env, sigs = Utils.type_check [] gospel in
+    and env, sigs =
+      match Filename.extension gospel with
+      | ".mli" -> Utils.type_check [] gospel
+      | ".gospel" -> Utils.read_gospel_file gospel
+      | _ -> invalid_arg "init"
+    in
     assert (List.length env = 1);
     let namespace = List.hd env in
     let context = Context.init module_name namespace in