diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2b08334..0734c65 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.12.6
+
++ Added unittests to `dei_args()`
+
 ## 0.12.5
 
 + Optimized dependencies: `setuptools` now no more a dependency
diff --git a/src/suou/__init__.py b/src/suou/__init__.py
index 0d1dc2d..6a434e4 100644
--- a/src/suou/__init__.py
+++ b/src/suou/__init__.py
@@ -38,7 +38,7 @@ from .http import WantsContentType
 from .color import OKLabColor, chalk, WebColor, RGBColor, LinearRGBColor, XYZColor, OKLCHColor
 from .mat import Matrix
 
-__version__ = "0.12.5"
+__version__ = "0.12.6"
 
 __all__ = (
     'ConfigOptions', 'ConfigParserConfigSource', 'ConfigSource', 'ConfigValue',
diff --git a/src/suou/dei.py b/src/suou/dei.py
index d114289..8d0f326 100644
--- a/src/suou/dei.py
+++ b/src/suou/dei.py
@@ -19,7 +19,7 @@ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 
 from __future__ import annotations
 from functools import wraps
-from typing import Callable, TypeVar
+from typing import Callable, Collection, TypeVar, Any
 
 _T = TypeVar('_T')
 _U = TypeVar('_U')
@@ -115,7 +115,7 @@ class Pronoun(int):
 
 
 
-def dei_args(**renames):
+def dei_args(**renames: dict[str, str]):
     """
     Allow for aliases in the keyword argument names, in form alias='real_name'.
 
@@ -125,7 +125,7 @@ def dei_args(**renames):
     Dear conservatives, this does not influence the ability to call the wrapped function
     with the original parameter names.
     """
-    def decorator(func: Callable[_T, _U]) -> Callable[_T, _U]:
+    def decorator(func: Callable[..., _U]) -> Callable[..., _U]:
         @wraps(func)
         def wrapper(*args, **kwargs):
             for alias_name, actual_name in renames.items():
diff --git a/tests/test_dei.py b/tests/test_dei.py
new file mode 100644
index 0000000..603e7f4
--- /dev/null
+++ b/tests/test_dei.py
@@ -0,0 +1,31 @@
+
+
+import unittest
+
+from suou import dei_args
+
+class TestDei(unittest.TestCase):
+    def setUp(self) -> None:
+        ...
+
+    def tearDown(self) -> None:
+        ...
+
+    def test_dei_args(self):
+        
+        def func_a(*, a: int, b: int):
+            """Trivial function for the purpose of the test"""
+            return a - b == 0
+
+        func_b = dei_args(c='a', d='b')(func_a)
+
+        with self.assertRaises(TypeError):
+            func_a(c=1, b=2)
+        
+        self.assertTrue(func_a(a=1, b=1))
+        self.assertFalse(func_b(c=1, b=2))
+        self.assertFalse(func_b(a=1, d=2))
+        self.assertFalse(func_b(a=1, b=2))
+        
+        with self.assertRaises(TypeError):
+            func_b(c=1, b="a")
\ No newline at end of file
diff --git a/tests/test_strtools.py b/tests/test_strtools.py
index e3ef328..ceaef12 100644
--- a/tests/test_strtools.py
+++ b/tests/test_strtools.py
@@ -1,6 +1,4 @@
 
-
-
 import unittest
 
 from suou.strtools import PrefixIdentifier
@@ -27,14 +25,11 @@ class TestStrtools(unittest.TestCase):
 
     def test_PrefixIdentifier_get_nostr(self):
         with self.assertRaises(TypeError):
-            pi = PrefixIdentifier(1)
-            pi.hello
+            PrefixIdentifier(1)
 
         with self.assertRaises(TypeError):
             PrefixIdentifier([99182])
         
         with self.assertRaises(TypeError):
             PrefixIdentifier(b'alpha_')
-    
-
-        
\ No newline at end of file
+     
\ No newline at end of file