diff --git a/Makefile b/Makefile
index ef04308..cf1c189 100644
--- a/Makefile
+++ b/Makefile
@@ -25,7 +25,7 @@ install:  ## install to site-packages
 test: ## run the python unit tests
 	python -m pytest -v ccflow/tests --cov=ccflow --cov-report xml --cov-report term-missing
 
-test: tests
+tests: test
 
 ###########
 # Linting #
diff --git a/ccflow/tests/result/test_generic.py b/ccflow/tests/result/test_generic.py
index af8c2b4..129ddf8 100644
--- a/ccflow/tests/result/test_generic.py
+++ b/ccflow/tests/result/test_generic.py
@@ -38,4 +38,4 @@ def test_generics_conversion(self):
         self.assertEqual(GenericResult[int](value=GenericContext[str](value=v)), GenericResult[int](value=v))
         self.assertEqual(GenericResult[int](value=GenericContext[int](value=v)), GenericResult[int](value=v))
 
-        self.assertEqual(GenericResult[str].validate(GenericContext(value=5)), GenericResult[str](value="5"))
+        self.assertEqual(GenericResult[str].model_validate(GenericContext(value=5)), GenericResult[str](value="5"))
diff --git a/ccflow/tests/test_base_serialize.py b/ccflow/tests/test_base_serialize.py
index f68485c..3065bb6 100644
--- a/ccflow/tests/test_base_serialize.py
+++ b/ccflow/tests/test_base_serialize.py
@@ -164,12 +164,8 @@ def test_numpy_serialize(self):
             self._check_serialization(H(arr=[1, 0]), self._numpy_equality)
 
         self._check_serialization(F(arr=["passes"]), self._numpy_equality)
-        self.assertRaises(
-            Exception,
-            self._check_serialization,
-            H_complex64(arr=[11, 12]),
-            self._numpy_equality,
-        )
+
+        self._check_serialization(H_complex64(arr=[11, 12]), self._numpy_equality)
 
         cut_off_array = H_int8(arr=[127, -128])
         np.testing.assert_array_equal(cut_off_array.arr, np.array([127, -128], dtype=np.int8))
diff --git a/ccflow/tests/test_lazy_result.py b/ccflow/tests/test_lazy_result.py
index 7f78e43..eecd03f 100644
--- a/ccflow/tests/test_lazy_result.py
+++ b/ccflow/tests/test_lazy_result.py
@@ -15,6 +15,7 @@ class MyResult(ResultBase):
     def _validate(self):
         # Track construction by incrementing the total each time the validation is called
         MyResult.total += 1
+        return self
 
 
 def test_make_lazy_result():
diff --git a/ccflow/tests/utils/test_chunker.py b/ccflow/tests/utils/test_chunker.py
index a10e59b..656c705 100644
--- a/ccflow/tests/utils/test_chunker.py
+++ b/ccflow/tests/utils/test_chunker.py
@@ -6,13 +6,13 @@
 
 class TestChunker(unittest.TestCase):
     def test_dates_to_chunks_M(self):
-        out = dates_to_chunks(date(2022, 4, 6), date(2022, 4, 7), "M")
+        out = dates_to_chunks(date(2022, 4, 6), date(2022, 4, 7), "ME")
         self.assertListEqual(out, [(date(2022, 4, 1), date(2022, 4, 30))])
 
-        out = dates_to_chunks(date(2022, 4, 1), date(2022, 4, 30), "M")
+        out = dates_to_chunks(date(2022, 4, 1), date(2022, 4, 30), "ME")
         self.assertListEqual(out, [(date(2022, 4, 1), date(2022, 4, 30))])
 
-        out = dates_to_chunks(date(2022, 3, 6), date(2022, 4, 7), "M")
+        out = dates_to_chunks(date(2022, 3, 6), date(2022, 4, 7), "ME")
         self.assertListEqual(
             out,
             [
@@ -20,7 +20,7 @@ def test_dates_to_chunks_M(self):
                 (date(2022, 4, 1), date(2022, 4, 30)),
             ],
         )
-        out = dates_to_chunks(date(2022, 1, 6), date(2022, 4, 7), "M")
+        out = dates_to_chunks(date(2022, 1, 6), date(2022, 4, 7), "ME")
         self.assertListEqual(
             out,
             [
@@ -65,13 +65,13 @@ def test_dates_to_chunks_d(self):
         self.assertListEqual(out, [])
 
     def test_dates_to_chunks_trim(self):
-        out = dates_to_chunks(date(2022, 4, 6), date(2022, 4, 7), "M", trim=True)
+        out = dates_to_chunks(date(2022, 4, 6), date(2022, 4, 7), "ME", trim=True)
         self.assertListEqual(out, [(date(2022, 4, 6), date(2022, 4, 7))])
 
-        out = dates_to_chunks(date(2022, 4, 1), date(2022, 4, 30), "M", trim=True)
+        out = dates_to_chunks(date(2022, 4, 1), date(2022, 4, 30), "ME", trim=True)
         self.assertListEqual(out, [(date(2022, 4, 1), date(2022, 4, 30))])
 
-        out = dates_to_chunks(date(2022, 3, 6), date(2022, 4, 7), "M", trim=True)
+        out = dates_to_chunks(date(2022, 3, 6), date(2022, 4, 7), "ME", trim=True)
         self.assertListEqual(
             out,
             [
@@ -79,7 +79,7 @@ def test_dates_to_chunks_trim(self):
                 (date(2022, 4, 1), date(2022, 4, 7)),
             ],
         )
-        out = dates_to_chunks(date(2022, 1, 6), date(2022, 4, 7), "M", trim=True)
+        out = dates_to_chunks(date(2022, 1, 6), date(2022, 4, 7), "ME", trim=True)
         self.assertListEqual(
             out,
             [