diff --git a/unittests/unittests_core/core_test_suite.py b/unittests/unittests_core/core_test_suite.py
index b1e0c96b..f3321712 100644
--- a/unittests/unittests_core/core_test_suite.py
+++ b/unittests/unittests_core/core_test_suite.py
@@ -3,6 +3,8 @@ import unittest
 from unittests_core.configuration.console_arguments_test_case import ConsoleArgumentsTestCase
 from unittests_core.configuration.configuration_test_case import ConfigurationTestCase
 from unittests_core.configuration.environment_test_case import EnvironmentTestCase
+from unittests_core.di.service_collection_test_case import ServiceCollectionTestCase
+from unittests_core.di.service_provider_test_case import ServiceProviderTestCase
 from unittests_core.pipes.bool_pipe_test_case import BoolPipeTestCase
 from unittests_core.pipes.ip_address_pipe_test_case import IPAddressTestCase
 from unittests_core.pipes.version_pipe_test_case import VersionPipeTestCase
@@ -21,6 +23,9 @@ class CoreTestSuite(unittest.TestSuite):
             ConfigurationTestCase,
             ConsoleArgumentsTestCase,
             EnvironmentTestCase,
+            # di
+            ServiceCollectionTestCase,
+            ServiceProviderTestCase,
             # pipes
             BoolPipeTestCase,
             IPAddressTestCase,
diff --git a/unittests/unittests_core/di/__init__.py b/unittests/unittests_core/di/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/unittests/unittests_core/di/service_collection_test_case.py b/unittests/unittests_core/di/service_collection_test_case.py
new file mode 100644
index 00000000..ba41797f
--- /dev/null
+++ b/unittests/unittests_core/di/service_collection_test_case.py
@@ -0,0 +1,56 @@
+import unittest
+from unittest.mock import Mock
+
+from cpl_core.configuration import Configuration
+from cpl_core.dependency_injection import ServiceCollection, ServiceLifetimeEnum, ServiceProviderABC
+
+
+class ServiceCollectionTestCase(unittest.TestCase):
+    def setUp(self):
+        self._sc = ServiceCollection(Configuration())
+
+    def test_add_singleton_type(self):
+        self._sc.add_singleton(Mock)
+
+        service = self._sc._service_descriptors[0]
+        self.assertEqual(ServiceLifetimeEnum.singleton, service.lifetime)
+        self.assertEqual(Mock, service.service_type)
+        self.assertEqual(Mock, service.base_type)
+        self.assertIsNone(service.implementation)
+
+    def test_add_singleton_instance(self):
+        mock = Mock()
+        self._sc.add_singleton(mock)
+
+        service = self._sc._service_descriptors[0]
+        self.assertEqual(ServiceLifetimeEnum.singleton, service.lifetime)
+        self.assertEqual(type(mock), service.service_type)
+        self.assertEqual(type(mock), service.base_type)
+        self.assertIsNotNone(service.implementation)
+
+    def test_add_transient_type(self):
+        self._sc.add_transient(Mock)
+
+        service = self._sc._service_descriptors[0]
+        self.assertEqual(ServiceLifetimeEnum.transient, service.lifetime)
+        self.assertEqual(Mock, service.service_type)
+        self.assertEqual(Mock, service.base_type)
+        self.assertIsNone(service.implementation)
+
+    def test_add_scoped_type(self):
+        self._sc.add_scoped(Mock)
+
+        service = self._sc._service_descriptors[0]
+        self.assertEqual(ServiceLifetimeEnum.scoped, service.lifetime)
+        self.assertEqual(Mock, service.service_type)
+        self.assertEqual(Mock, service.base_type)
+        self.assertIsNone(service.implementation)
+
+    def test_build_service_provider(self):
+        self._sc.add_singleton(Mock)
+        service = self._sc._service_descriptors[0]
+        self.assertIsNone(service.implementation)
+        sp = self._sc.build_service_provider()
+        self.assertTrue(isinstance(sp, ServiceProviderABC))
+        self.assertTrue(isinstance(sp.get_service(Mock), Mock))
+        self.assertIsNotNone(service.implementation)
diff --git a/unittests/unittests_core/di/service_provider_test_case.py b/unittests/unittests_core/di/service_provider_test_case.py
new file mode 100644
index 00000000..637a8aa8
--- /dev/null
+++ b/unittests/unittests_core/di/service_provider_test_case.py
@@ -0,0 +1,85 @@
+import unittest
+
+from cpl_core.configuration import Configuration
+from cpl_core.dependency_injection import ServiceCollection, ServiceProviderABC
+
+
+class ServiceCount:
+    def __init__(self):
+        self.count = 0
+
+
+class TestService:
+    def __init__(self, count: ServiceCount):
+        count.count += 1
+        self.id = count.count
+
+
+class DifferentService:
+    def __init__(self, count: ServiceCount):
+        count.count += 1
+        self.id = count.count
+
+
+class MoreDifferentService:
+    def __init__(self, count: ServiceCount):
+        count.count += 1
+        self.id = count.count
+
+
+class ServiceProviderTestCase(unittest.TestCase):
+    def setUp(self):
+        self._services = (
+            ServiceCollection(Configuration())
+            .add_singleton(ServiceCount)
+            .add_singleton(TestService)
+            .add_singleton(TestService)
+            .add_transient(DifferentService)
+            .add_scoped(MoreDifferentService)
+            .build_service_provider()
+        )
+
+        count = self._services.get_service(ServiceCount)
+
+    def test_get_singleton(self):
+        x = self._services.get_service(TestService)
+        self.assertIsNotNone(x)
+        self.assertEqual(1, x.id)
+        self.assertEqual(x, self._services.get_service(TestService))
+        self.assertEqual(x, self._services.get_service(TestService))
+        self.assertEqual(x, self._services.get_service(TestService))
+
+    def test_get_singletons(self):
+        x = self._services.get_services(list[TestService])
+        self.assertEqual(2, len(x))
+        self.assertEqual(1, x[0].id)
+        self.assertEqual(2, x[1].id)
+        self.assertNotEqual(x[0], x[1])
+
+    def test_get_transient(self):
+        x = self._services.get_service(DifferentService)
+        self.assertIsNotNone(x)
+        self.assertEqual(1, x.id)
+        self.assertNotEqual(x, self._services.get_service(DifferentService))
+        self.assertNotEqual(x, self._services.get_service(DifferentService))
+        self.assertNotEqual(x, self._services.get_service(DifferentService))
+
+    def test_scoped(self):
+        scoped_id = 0
+        singleton = self._services.get_service(TestService)
+        with self._services.create_scope() as scope:
+            sp: ServiceProviderABC = scope.service_provider
+            y = sp.get_service(DifferentService)
+            self.assertIsNotNone(y)
+            self.assertEqual(2, y.id)
+            x = sp.get_service(MoreDifferentService)
+            self.assertIsNotNone(x)
+            self.assertEqual(3, x.id)
+            scoped_id = 3
+            self.assertEqual(x.id, sp.get_service(MoreDifferentService).id)
+            self.assertEqual(x.id, sp.get_service(MoreDifferentService).id)
+            self.assertNotEqual(x, self._services.get_service(MoreDifferentService))
+            self.assertEqual(singleton, self._services.get_service(TestService))
+
+        self.assertIsNone(scope.service_provider)
+        self.assertNotEqual(scoped_id, self._services.get_service(MoreDifferentService).id)