diff --git a/src/risotto/message.py b/src/risotto/message.py
index 642f7ee7..c99710b4 100644
--- a/src/risotto/message.py
+++ b/src/risotto/message.py
@@ -15,8 +15,6 @@ from .utils import _
 
 
 MESSAGE_ROOT_PATH = get_config()['global']['message_root_path']
-CUSTOMTYPES = {}
-
 groups.addgroup('message')
 
 
@@ -388,13 +386,14 @@ class CustomType:
         return self.title
 
 
-def load_customtypes(current_module_names: str) -> None:
+def load_customtypes() -> None:
     versions = listdir(MESSAGE_ROOT_PATH)
     versions.sort()
+    ret = {}
     for version in versions:
-        if version not in CUSTOMTYPES:
-            CUSTOMTYPES[version] = {}
-        for current_module_name in current_module_names:
+        if version not in ret:
+            ret[version] = {}
+        for current_module_name in listdir(join(MESSAGE_ROOT_PATH, version)):
             types_path = join(MESSAGE_ROOT_PATH,
                               version,
                               current_module_name,
@@ -407,10 +406,10 @@ def load_customtypes(current_module_names: str) -> None:
                     with open(path, "r") as message_file:
                         try:
                             custom_type = CustomType(load(message_file, Loader=SafeLoader))
-                            CUSTOMTYPES[version][custom_type.getname()] = custom_type
+                            ret[version][custom_type.getname()] = custom_type
                         except Exception as err:
                             raise Exception(_(f'enable to load type {err}: {message}'))
-
+    return ret
 
 
 def _get_description(description,
@@ -577,7 +576,6 @@ def get_messages(current_module_names,
                  uris=None):
     """generate description from yml files
     """
-    global CUSTOMTYPES
     optiondescriptions = {}
     optiondescriptions_info = {}
     messages = list(list_messages(uris,
@@ -589,14 +587,6 @@ def get_messages(current_module_names,
                                  'Nom du message.',
                                  tuple(optiondescriptions_name),
                                  properties=frozenset(['mandatory', 'positional']))
-    if current_module_names is None:
-        CUSTOMTYPES = {}
-    if not CUSTOMTYPES:
-        if current_module_names is None:
-            for version in listdir(MESSAGE_ROOT_PATH):
-                load_customtypes(listdir(join(MESSAGE_ROOT_PATH, version)))
-        else:
-            load_customtypes(current_module_names)
     for uri in messages:
         message_def = get_message(uri,
                                   current_module_names,
@@ -620,6 +610,7 @@ def get_messages(current_module_names,
 
     root = _get_root_option(select_option,
                             optiondescriptions)
-    if current_module_names is None:
-        CUSTOMTYPES = {}
     return optiondescriptions_info, root
+
+
+CUSTOMTYPES = load_customtypes()