diff --git a/tiramisu_cmdline_parser/__init__.py b/tiramisu_cmdline_parser/__init__.py
index 978c1a4..83f9863 100644
--- a/tiramisu_cmdline_parser/__init__.py
+++ b/tiramisu_cmdline_parser/__init__.py
@@ -1,4 +1,4 @@
-from .tiramisu_cmdline_parser import TiramisuCmdlineParser
+from .api import TiramisuCmdlineParser
 
 __version__ = "0.0.1"
 __all__ = ('TiramisuCmdlineParser',)
diff --git a/tiramisu_cmdline_parser/tiramisu_cmdline_parser.py b/tiramisu_cmdline_parser/api.py
similarity index 97%
rename from tiramisu_cmdline_parser/tiramisu_cmdline_parser.py
rename to tiramisu_cmdline_parser/api.py
index 7d1fd3d..571a4b7 100644
--- a/tiramisu_cmdline_parser/tiramisu_cmdline_parser.py
+++ b/tiramisu_cmdline_parser/api.py
@@ -15,6 +15,7 @@
 from typing import Union, List, Optional
 from argparse import ArgumentParser, Namespace, SUPPRESS, _HelpAction, HelpFormatter
 from copy import copy
+from gettext import gettext as _
 
 
 try:
@@ -139,13 +140,13 @@ class TiramisuCmdlineParser(ArgumentParser):
         if args == ('-h', '--help'):
             super().add_argument(*args, **kwargs)
         else:
-            raise NotImplementedError('do not use add_argument')
+            raise NotImplementedError(_('do not use add_argument'))
 
     def add_arguments(self, *args, **kwargs):
-        raise NotImplementedError('do not use add_argument')
+        raise NotImplementedError(_('do not use add_argument'))
 
     def add_subparsers(self, *args, **kwargs):
-        raise NotImplementedError('do not use add_subparsers')
+        raise NotImplementedError(_('do not use add_subparsers'))
 
     def _gen_argument(self, name, longargument, no_prefix=False):
         shortarg = len(name) == 1 and not longargument
@@ -186,7 +187,7 @@ class TiramisuCmdlineParser(ArgumentParser):
                 continue
             name = option.name()
             if name.startswith(self.prefix_chars):
-                raise ValueError('name cannot startswith "{}"'.format(self.prefix_chars))
+                raise ValueError(_('name cannot startswith "{}"').format(self.prefix_chars))
             if self.fullpath and prefix:
                 name = prefix + '.' + name
             properties = obj.property.get()
@@ -206,7 +207,7 @@ class TiramisuCmdlineParser(ArgumentParser):
             else:
                 if 'positional' in properties:
                     if option.type() == 'boolean':
-                        raise ValueError('boolean option must not be positional')
+                        raise ValueError(_('boolean option must not be positional'))
                     # if not 'mandatory' in properties:
                     #     raise ValueError('"positional" argument must be "mandatory" too')
                     args = [option.path()]