diff --git a/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_component_modules.cpp b/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_component_modules.cpp
index d0b54e48d4..00cd62489e 100644
--- a/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_component_modules.cpp
+++ b/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_component_modules.cpp
@@ -19,7 +19,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 
 int main(int argc, char* argv[])
diff --git a/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_example_base_class.cpp b/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_example_base_class.cpp
index 5f6b23f17c..3f9f827a3c 100644
--- a/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_example_base_class.cpp
+++ b/doc/aspice_swe3_4/example/iceoryx_component/test/moduletests/test_example_base_class.cpp
@@ -20,13 +20,10 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
-namespace example
-{
-namespace test
-{
 /// @req IOX_SWRS_112, IOX_SWRS_200
 /// @brief Test goal: "This test suite verifies that the BaseClass function is verified"
 /// @pre describe what needs to be done in setup()
@@ -51,5 +48,4 @@ TEST_F(ExampleBaseClass_test, GetMemberVariableFromCtor)
     EXPECT_THAT(sut2.getMemberVariable(), Eq(99U));
 }
 
-} // namespace test
-} // namespace example
\ No newline at end of file
+} // namespace
diff --git a/iceoryx_binding_c/test/moduletests/main.cpp b/iceoryx_binding_c/test/moduletests/main.cpp
index d6a24275a2..77fe11c888 100644
--- a/iceoryx_binding_c/test/moduletests/main.cpp
+++ b/iceoryx_binding_c/test/moduletests/main.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,7 +19,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 int main(int argc, char* argv[])
 {
diff --git a/iceoryx_dds/test/moduletests/main.cpp b/iceoryx_dds/test/moduletests/main.cpp
index d6a24275a2..77fe11c888 100644
--- a/iceoryx_dds/test/moduletests/main.cpp
+++ b/iceoryx_dds/test/moduletests/main.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,7 +19,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 int main(int argc, char* argv[])
 {
diff --git a/iceoryx_dds/test/moduletests/test_iox_to_dds.cpp b/iceoryx_dds/test/moduletests/test_iox_to_dds.cpp
index b10b9b20e6..83ff178854 100644
--- a/iceoryx_dds/test/moduletests/test_iox_to_dds.cpp
+++ b/iceoryx_dds/test/moduletests/test_iox_to_dds.cpp
@@ -35,7 +35,6 @@
 using namespace ::testing;
 using ::testing::_;
 using ::testing::InSequence;
-using ::testing::Return;
 using ::testing::SetArgPointee;
 
 // ======================================== Helpers ======================================== //
diff --git a/iceoryx_posh/test/integrationtests/service_discovery/test_roudi_service_discovery.hpp b/iceoryx_posh/test/integrationtests/service_discovery/test_roudi_service_discovery.hpp
deleted file mode 100644
index 742be9f7d4..0000000000
--- a/iceoryx_posh/test/integrationtests/service_discovery/test_roudi_service_discovery.hpp
+++ /dev/null
@@ -1,52 +0,0 @@
-// Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
-// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-// SPDX-License-Identifier: Apache-2.0
-
-#ifndef IOX_POSH_SERVICE_DISCOVERY_TEST_ROUDI_SERVICE_DISCOVERY_HPP
-#define IOX_POSH_SERVICE_DISCOVERY_TEST_ROUDI_SERVICE_DISCOVERY_HPP
-
-#include "iceoryx_posh/testing/roudi_gtest.hpp"
-
-using iox::capro::IdString_t;
-using iox::runtime::InstanceContainer;
-
-template <class T, uint64_t Capacity>
-class vector_init_list : public iox::cxx::vector<T, Capacity>
-{
-  public:
-    vector_init_list(std::initializer_list<T> l)
-    {
-        for (auto& i : l)
-        {
-            iox::cxx::vector<T, Capacity>::push_back(i);
-        }
-    }
-};
-
-class RouDiServiceDiscoveryTest : public RouDi_GTest
-{
-  protected:
-    void InitContainer(InstanceContainer& dest, std::vector<std::string> src)
-    {
-        dest.clear();
-        for (size_t i = 0; i < src.size(); i++)
-        {
-            dest.push_back(IdString_t(iox::cxx::TruncateToCapacity, src[i]));
-        }
-    }
-};
-
-#endif // IOX_POSH_SERVICE_DISCOVERY_TEST_ROUDI_SERVICE_DISCOVERY_HPP
diff --git a/iceoryx_posh/test/integrationtests/test_interface_port_stack_blowup.cpp b/iceoryx_posh/test/integrationtests/test_interface_port_stack_blowup.cpp
index ff7970dc55..f4298b138d 100644
--- a/iceoryx_posh/test/integrationtests/test_interface_port_stack_blowup.cpp
+++ b/iceoryx_posh/test/integrationtests/test_interface_port_stack_blowup.cpp
@@ -22,8 +22,9 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::gw;
 
@@ -42,3 +43,5 @@ TEST_F(InterfacePortRequestStackBlowup_test, RouDiMustContinue)
     // we don't care if there are capro messages or not, we just want to have a check that there was no segfault
     EXPECT_THAT(sut.getCaProMessage(caproMessage), AnyOf(true, false));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_mq_interface_startup_race.cpp b/iceoryx_posh/test/integrationtests/test_mq_interface_startup_race.cpp
index e69d4cce27..167e9f5d38 100644
--- a/iceoryx_posh/test/integrationtests/test_mq_interface_startup_race.cpp
+++ b/iceoryx_posh/test/integrationtests/test_mq_interface_startup_race.cpp
@@ -29,6 +29,8 @@
 #include <mutex>
 #include <thread>
 
+namespace
+{
 using namespace ::testing;
 using namespace iox;
 using namespace iox::units;
@@ -266,3 +268,5 @@ TEST_F(CMqInterfaceStartupRace_test, ObsoleteRegAck)
     auto response = m_appQueue->timedReceive(10_ms);
     EXPECT_THAT(response.has_error(), Eq(true));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_popo_chunk_building_blocks.cpp b/iceoryx_posh/test/integrationtests/test_popo_chunk_building_blocks.cpp
index efb132e272..cd44be8433 100644
--- a/iceoryx_posh/test/integrationtests/test_popo_chunk_building_blocks.cpp
+++ b/iceoryx_posh/test/integrationtests/test_popo_chunk_building_blocks.cpp
@@ -29,12 +29,13 @@
 #include <stdlib.h>
 #include <thread>
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::popo;
 using namespace iox::cxx;
 using namespace iox::mepoo;
 using namespace iox::posix;
-using ::testing::Return;
 
 struct DummySample
 {
@@ -252,3 +253,5 @@ TEST_F(ChunkBuildingBlocks_IntegrationTest, TwoHopsThreeThreadsNoSoFi)
     ASSERT_FALSE(m_chunkReceiver.hasLostChunks());
     EXPECT_EQ(m_sendCounter, m_receiveCounter);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_popo_port_user_building_blocks.cpp b/iceoryx_posh/test/integrationtests/test_popo_port_user_building_blocks.cpp
index 816b1cd6fd..0ae07a82c7 100644
--- a/iceoryx_posh/test/integrationtests/test_popo_port_user_building_blocks.cpp
+++ b/iceoryx_posh/test/integrationtests/test_popo_port_user_building_blocks.cpp
@@ -32,13 +32,14 @@
 #include <sstream>
 #include <thread>
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::popo;
 using namespace iox::capro;
 using namespace iox::cxx;
 using namespace iox::mepoo;
 using namespace iox::posix;
-using ::testing::Return;
 
 struct DummySample
 {
@@ -383,3 +384,5 @@ TIMING_TEST_F(PortUser_IntegrationTest, MultiProducer, Repeat(5), [&] {
     TIMING_TEST_EXPECT_TRUE(m_sendCounter.load(std::memory_order_relaxed) == m_receiveCounter);
     TIMING_TEST_EXPECT_FALSE(PortUser_IntegrationTest::m_subscriberPortUserMultiProducer.hasLostChunksSinceLastCall());
 });
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_popo_pub_sub_listener.cpp b/iceoryx_posh/test/integrationtests/test_popo_pub_sub_listener.cpp
index d8900284cf..8f1391bcff 100644
--- a/iceoryx_posh/test/integrationtests/test_popo_pub_sub_listener.cpp
+++ b/iceoryx_posh/test/integrationtests/test_popo_pub_sub_listener.cpp
@@ -22,15 +22,14 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::popo;
 using namespace iox::capro;
 using namespace iox::runtime;
 
-namespace
-{
 void onSampleReceivedCallback(Subscriber<int>* subscriber IOX_MAYBE_UNUSED)
 {
 }
@@ -58,7 +57,6 @@ class PubSubListener_IntegrationTest : public RouDi_GTest
     std::unique_ptr<Subscriber<int>> m_subscriber;
     std::unique_ptr<UntypedSubscriber> m_untypedSubscriber;
 };
-} // namespace
 
 /// @note Here we test that the trigger reset methods are called correctly in the d'tor of SubscriberImpl. They must not
 /// be called in the BaseSubscriber d'tor since the SubscriberImpl was attached to the Listener. When it goes out of
@@ -90,3 +88,4 @@ TEST_F(PubSubListener_IntegrationTest, UntypedSubscriberGoesOutOfScopeAndDetachi
     m_untypedSubscriber.reset();
 }
 
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_posh_integration.cpp b/iceoryx_posh/test/integrationtests/test_posh_integration.cpp
index 6f0bd76b17..232714c6a7 100644
--- a/iceoryx_posh/test/integrationtests/test_posh_integration.cpp
+++ b/iceoryx_posh/test/integrationtests/test_posh_integration.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -20,7 +21,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 int main(int argc, char* argv[])
 {
diff --git a/iceoryx_posh/test/integrationtests/test_posh_mepoo.cpp b/iceoryx_posh/test/integrationtests/test_posh_mepoo.cpp
index c8ca007828..026b2284ac 100644
--- a/iceoryx_posh/test/integrationtests/test_posh_mepoo.cpp
+++ b/iceoryx_posh/test/integrationtests/test_posh_mepoo.cpp
@@ -40,11 +40,12 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::units::duration_literals;
 using iox::mepoo::MePooConfig;
 using iox::roudi::RouDiEnvironment;
-using ::testing::Return;
 
 using iox::posix::Timer;
 
@@ -445,3 +446,5 @@ TIMING_TEST_F(Mepoo_IntegrationTest, MempoolCreationTimeDefaultConfig, Repeat(5)
     auto maxtime = 2000_ms;
     EXPECT_THAT(timediff, Le(maxtime));
 });
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_publisher_subscriber_communication.cpp b/iceoryx_posh/test/integrationtests/test_publisher_subscriber_communication.cpp
index 45c727a9bb..4f1f425843 100644
--- a/iceoryx_posh/test/integrationtests/test_publisher_subscriber_communication.cpp
+++ b/iceoryx_posh/test/integrationtests/test_publisher_subscriber_communication.cpp
@@ -30,15 +30,14 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox;
 using namespace iox::popo;
 using namespace iox::cxx;
 
-namespace
-{
 template <typename T>
 struct ComplexDataType
 {
@@ -81,7 +80,6 @@ class PublisherSubscriberCommunication_test : public RouDi_GTest
     capro::ServiceDescription m_serviceDescription{
         "PublisherSubscriberCommunication", "IntegrationTest", "AllHailHypnotoad"};
 };
-} // namespace
 
 TEST_F(PublisherSubscriberCommunication_test, SendingComplexDataType_forward_list)
 {
@@ -464,3 +462,5 @@ TEST_F(PublisherSubscriberCommunication_test, MixedOptionsSetupWorksWithBlocking
     EXPECT_THAT(subscriberNonBlocking->take().has_error(), Eq(true));
 
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/service_discovery/test_roudi_findservice.cpp b/iceoryx_posh/test/integrationtests/test_roudi_findservice.cpp
similarity index 97%
rename from iceoryx_posh/test/integrationtests/service_discovery/test_roudi_findservice.cpp
rename to iceoryx_posh/test/integrationtests/test_roudi_findservice.cpp
index 0eb1ad379a..9ae5c67043 100644
--- a/iceoryx_posh/test/integrationtests/service_discovery/test_roudi_findservice.cpp
+++ b/iceoryx_posh/test/integrationtests/test_roudi_findservice.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019, 2021 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,10 +16,15 @@
 // SPDX-License-Identifier: Apache-2.0
 
 #include "iceoryx_posh/runtime/posh_runtime.hpp"
+#include "iceoryx_posh/testing/roudi_gtest.hpp"
 #include "iceoryx_utils/cxx/convert.hpp"
-#include "test_roudi_service_discovery.hpp"
 
-class RoudiFindService_test : public RouDiServiceDiscoveryTest
+namespace
+{
+using iox::capro::IdString_t;
+using iox::runtime::InstanceContainer;
+
+class RoudiFindService_test : public RouDi_GTest
 {
   public:
     void SetUp()
@@ -195,7 +201,9 @@ TEST_F(RoudiFindService_test, SubscribeAnyInstance)
     senderRuntime->offerService({"service1", "instance3"});
     this->InterOpWait();
     InstanceContainer instanceContainerExp;
-    InitContainer(instanceContainerExp, {"instance1", "instance2", "instance3"});
+    instanceContainerExp.push_back("instance1");
+    instanceContainerExp.push_back("instance2");
+    instanceContainerExp.push_back("instance3");
 
     auto instanceContainer = receiverRuntime->findService({"service1", iox::capro::AnyServiceString});
 
@@ -397,3 +405,5 @@ TEST_F(RoudiFindService_test, findServiceInstanceContainerOverflowError)
 
     ASSERT_THAT(instanceContainer.has_error(), Eq(true));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/integrationtests/test_roudi_roudi_environment.cpp b/iceoryx_posh/test/integrationtests/test_roudi_roudi_environment.cpp
index dbcf1dddda..59a335ac5c 100644
--- a/iceoryx_posh/test/integrationtests/test_roudi_roudi_environment.cpp
+++ b/iceoryx_posh/test/integrationtests/test_roudi_roudi_environment.cpp
@@ -19,9 +19,10 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::roudi;
-using ::testing::Return;
 
 class RouDiEnvironment_test : public Test
 {
@@ -35,3 +36,5 @@ TEST_F(RouDiEnvironment_test, StartingRouDiTwiceLeadsToError)
     RouDiEnvironment m_sut{iox::RouDiConfig_t().setDefaults()};
     EXPECT_DEATH({ RouDiEnvironment m_sut2{iox::RouDiConfig_t().setDefaults()}; }, ".*");
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_base_port.cpp b/iceoryx_posh/test/moduletests/test_base_port.cpp
index f7c5331477..ec0890701a 100644
--- a/iceoryx_posh/test/moduletests/test_base_port.cpp
+++ b/iceoryx_posh/test/moduletests/test_base_port.cpp
@@ -28,6 +28,8 @@
 #include "iceoryx_utils/cxx/helplets.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::capro;
 using namespace iox::popo;
@@ -175,3 +177,5 @@ TYPED_TEST(BasePort_test, CallingGetRuntimeNameWorks)
     using PortData_t = typename TestFixture::PortData_t;
     EXPECT_THAT(this->sut.getRuntimeName(), Eq(expectedProcessName<PortData_t>()));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_capro_message.cpp b/iceoryx_posh/test/moduletests/test_capro_message.cpp
index 2a748a4112..f068b6c1e6 100644
--- a/iceoryx_posh/test/moduletests/test_capro_message.cpp
+++ b/iceoryx_posh/test/moduletests/test_capro_message.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2020 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -21,6 +22,8 @@
 #include "iceoryx_utils/cxx/generic_raii.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::capro;
 
@@ -58,3 +61,5 @@ TEST_F(CaproMessage_test, DefaultArgsOfCtor)
     EXPECT_EQ(CaproMessageSubType::NOSUBTYPE, testObj.m_subType);
     EXPECT_EQ(nullptr, testObj.m_chunkQueueData);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_capro_service.cpp b/iceoryx_posh/test/moduletests/test_capro_service.cpp
index 64271e6bc4..17d25ea4ef 100644
--- a/iceoryx_posh/test/moduletests/test_capro_service.cpp
+++ b/iceoryx_posh/test/moduletests/test_capro_service.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019, 2021 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -23,8 +24,9 @@
 
 #include <cstdint>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::capro;
 
@@ -675,3 +677,5 @@ TEST_F(ServiceDescription_test, LessThanOperatorReturnsFalseIfEventStringOfFirst
 }
 
 /// END SERVICEDESCRIPTION TESTS
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_compatibility_check_level.cpp b/iceoryx_posh/test/moduletests/test_compatibility_check_level.cpp
index 6724173a23..1515c37329 100644
--- a/iceoryx_posh/test/moduletests/test_compatibility_check_level.cpp
+++ b/iceoryx_posh/test/moduletests/test_compatibility_check_level.cpp
@@ -25,6 +25,8 @@
 #include <cstdint>
 #include <limits>
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::version;
 
@@ -122,3 +124,5 @@ TEST_F(CompatibilityCheckLevel_test, BuildDateLeadsToCorrectString)
     EXPECT_THAT(m_loggerMock.m_logs[0].message, Eq("CompatibilityCheckLevel::BUILD_DATE"));
     EXPECT_THAT(m_loggerMock.m_logs[0].level, Eq(iox::log::LogLevel::kWarn));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_fixed_size_container.cpp b/iceoryx_posh/test/moduletests/test_fixed_size_container.cpp
index 2c9812c58a..089c05ea94 100644
--- a/iceoryx_posh/test/moduletests/test_fixed_size_container.cpp
+++ b/iceoryx_posh/test/moduletests/test_fixed_size_container.cpp
@@ -1,4 +1,5 @@
-// Copyright (c) 2019, 2021 by Robert Bosch GmbH, Apex.AI Inc. All rights reserved.
+// Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,8 +20,9 @@
 
 #include <cstdint>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::roudi;
 
@@ -201,3 +203,5 @@ TEST_F(FixedSizeContainer_test, removeAndVerifyMultiElementContainer)
         }
     }
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_gw_channel.cpp b/iceoryx_posh/test/moduletests/test_gw_channel.cpp
index 4a83c22775..34f2eee778 100644
--- a/iceoryx_posh/test/moduletests/test_gw_channel.cpp
+++ b/iceoryx_posh/test/moduletests/test_gw_channel.cpp
@@ -20,6 +20,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
@@ -58,3 +60,5 @@ TEST_F(ChannelTest, ReturnsEmptyOptionalIfObjectPoolExhausted)
         {"", "", ""}, StubbedIceoryxTerminal::Options());
     EXPECT_FALSE(channel.has_error());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_gw_gateway_discovery.cpp b/iceoryx_posh/test/moduletests/test_gw_gateway_discovery.cpp
index f9cf5fba6d..99d5e77006 100644
--- a/iceoryx_posh/test/moduletests/test_gw_gateway_discovery.cpp
+++ b/iceoryx_posh/test/moduletests/test_gw_gateway_discovery.cpp
@@ -1,4 +1,5 @@
-// Copyright (c) 2019, 2021 by Robert Bosch GmbH, Apex.AI Inc. All rights reserved.
+// Copyright (c) 2019 - 2020 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,8 +20,9 @@
 #include "iceoryx_posh/gateway/gateway_discovery.hpp"
 #include "iceoryx_posh/internal/popo/ports/base_port.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using CaproMessage = iox::capro::CaproMessage;
 using BasePort = iox::popo::BasePort;
@@ -65,3 +67,5 @@ TEST_F(GatewayDiscovery_test, GetCaproMessage)
     EXPECT_EQ(iox::capro::CaproMessageType::ACK, msg.m_type);
     EXPECT_EQ(iox::capro::ServiceDescription(), msg.m_serviceDescription);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_gw_gateway_generic.cpp b/iceoryx_posh/test/moduletests/test_gw_gateway_generic.cpp
index 7e59b15bd0..7048a4797f 100644
--- a/iceoryx_posh/test/moduletests/test_gw_gateway_generic.cpp
+++ b/iceoryx_posh/test/moduletests/test_gw_gateway_generic.cpp
@@ -25,6 +25,8 @@
 
 #include "stubs/stub_gateway_generic.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::units::duration_literals;
 using ::testing::_;
@@ -262,3 +264,5 @@ TEST_F(GatewayGenericTest, ForEachChannelExecutesGivenFunctionForAllStoredChanne
 
     EXPECT_EQ(3U, count);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mepoo_mempool.cpp b/iceoryx_posh/test/moduletests/test_mepoo_mempool.cpp
index c81b9a426a..40e2281b4e 100644
--- a/iceoryx_posh/test/moduletests/test_mepoo_mempool.cpp
+++ b/iceoryx_posh/test/moduletests/test_mepoo_mempool.cpp
@@ -19,6 +19,8 @@
 #include "iceoryx_utils/internal/posix_wrapper/shared_memory_object/allocator.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::mepoo;
 
@@ -217,3 +219,5 @@ TEST_F(MemPool_test, dieWhenMempoolChunkSizeIsNotPowerOf32)
 {
     EXPECT_DEATH({ iox::mepoo::MemPool sut(333, 10, allocator, allocator); }, ".*");
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mepoo_segment.cpp b/iceoryx_posh/test/moduletests/test_mepoo_segment.cpp
index eea9ed9f77..de530a3cf0 100644
--- a/iceoryx_posh/test/moduletests/test_mepoo_segment.cpp
+++ b/iceoryx_posh/test/moduletests/test_mepoo_segment.cpp
@@ -30,10 +30,6 @@
 #include <functional>
 #include <memory>
 
-using namespace ::testing;
-using namespace iox::mepoo;
-using namespace iox::posix;
-
 namespace iox
 {
 namespace cxx
@@ -48,6 +44,13 @@ struct ErrorTypeAdapter<int>
 };
 } // namespace cxx
 } // namespace iox
+
+namespace
+{
+using namespace ::testing;
+using namespace iox::mepoo;
+using namespace iox::posix;
+
 class MePooSegment_test : public Test
 {
   public:
@@ -205,3 +208,5 @@ TEST_F(MePooSegment_test, ADD_TEST_WITH_ADDITIONAL_USER(GetMemoryManager))
     auto chunk = sut.getMemoryManager().getChunk(chunkSettings);
     EXPECT_THAT(chunk.getChunkHeader()->userPayloadSize(), Eq(USER_PAYLOAD_SIZE));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mepoo_segment_management.cpp b/iceoryx_posh/test/moduletests/test_mepoo_segment_management.cpp
index 9beb7462a2..cb587e9f80 100644
--- a/iceoryx_posh/test/moduletests/test_mepoo_segment_management.cpp
+++ b/iceoryx_posh/test/moduletests/test_mepoo_segment_management.cpp
@@ -27,6 +27,8 @@
 #include "test.hpp"
 
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::mepoo;
 using namespace iox::posix;
@@ -196,3 +198,5 @@ TEST_F(SegmentManager_test, ADD_TEST_WITH_ADDITIONAL_USER(addingMaximumNumberOfS
     SegmentConfig segmentConfig = getSegmentConfigWithMaximumNumberOfSegements();
     SegmentManager<MePooSegmentMock> sut{segmentConfig, &allocator};
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mepoo_shared_chunk.cpp b/iceoryx_posh/test/moduletests/test_mepoo_shared_chunk.cpp
index eaac91791d..459d15ad21 100644
--- a/iceoryx_posh/test/moduletests/test_mepoo_shared_chunk.cpp
+++ b/iceoryx_posh/test/moduletests/test_mepoo_shared_chunk.cpp
@@ -21,6 +21,8 @@
 #include "iceoryx_utils/internal/posix_wrapper/shared_memory_object/allocator.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::mepoo;
@@ -270,3 +272,5 @@ TEST_F(SharedChunk_Test, MultipleChunksCleanup)
     EXPECT_THAT(mempool.getUsedChunks(), Eq(1));
     EXPECT_THAT(chunkMgmtPool.getUsedChunks(), Eq(1));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mepoo_shared_pointer.cpp b/iceoryx_posh/test/moduletests/test_mepoo_shared_pointer.cpp
index b8008f0ae3..ba10f64bca 100644
--- a/iceoryx_posh/test/moduletests/test_mepoo_shared_pointer.cpp
+++ b/iceoryx_posh/test/moduletests/test_mepoo_shared_pointer.cpp
@@ -22,6 +22,8 @@
 #include "iceoryx_utils/internal/relocatable_pointer/base_relative_pointer.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::mepoo;
@@ -361,3 +363,5 @@ TEST_F(SharedPointer_Test, SharedPointerWithContentIsValid)
     auto sut3 = SharedPointer<TestClass>::create(chunk3, 1, 2).value();
     EXPECT_THAT(static_cast<bool>(sut3), Eq(true));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mepoo_typed_mempool.cpp b/iceoryx_posh/test/moduletests/test_mepoo_typed_mempool.cpp
index 4d15ed2093..e91e40108b 100644
--- a/iceoryx_posh/test/moduletests/test_mepoo_typed_mempool.cpp
+++ b/iceoryx_posh/test/moduletests/test_mepoo_typed_mempool.cpp
@@ -22,6 +22,24 @@
 
 #include "test.hpp"
 
+namespace iox
+{
+namespace cxx
+{
+template <>
+struct ErrorTypeAdapter<cxx::variant<mepoo::TypedMemPoolError, posix::SemaphoreError>>
+{
+    static variant<mepoo::TypedMemPoolError, posix::SemaphoreError> getInvalidState()
+    {
+        return variant<mepoo::TypedMemPoolError, posix::SemaphoreError>(iox::cxx::in_place_index<0>(),
+                                                                        mepoo::TypedMemPoolError::INVALID_STATE);
+    };
+};
+} // namespace cxx
+} // namespace iox
+
+namespace
+{
 using namespace ::testing;
 using namespace iox::mepoo;
 class TypedMemPool_test : public Test
@@ -61,22 +79,6 @@ class TypedMemPool_test : public Test
     TypedMemPool<TestClass> sut;
 };
 
-namespace iox
-{
-namespace cxx
-{
-template <>
-struct ErrorTypeAdapter<cxx::variant<mepoo::TypedMemPoolError, posix::SemaphoreError>>
-{
-    static variant<mepoo::TypedMemPoolError, posix::SemaphoreError> getInvalidState()
-    {
-        return variant<mepoo::TypedMemPoolError, posix::SemaphoreError>(iox::cxx::in_place_index<0>(),
-                                                                        mepoo::TypedMemPoolError::INVALID_STATE);
-    };
-};
-} // namespace cxx
-} // namespace iox
-
 TEST_F(TypedMemPool_test, GetOneObject)
 {
     auto object = sut.createObject(1, 223);
@@ -148,3 +150,5 @@ TEST_F(TypedMemPool_Semaphore_test, CreateInvalidSemaphore)
         iox::posix::CreateNamedSemaphore, "", S_IRUSR | S_IWUSR, 10);
     EXPECT_THAT(semaphorePtr.has_error(), Eq(true));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_monitoringmode_logstream.cpp b/iceoryx_posh/test/moduletests/test_monitoringmode_logstream.cpp
index d666ca3d95..7c6d48e8f9 100644
--- a/iceoryx_posh/test/moduletests/test_monitoringmode_logstream.cpp
+++ b/iceoryx_posh/test/moduletests/test_monitoringmode_logstream.cpp
@@ -21,6 +21,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::roudi;
 
@@ -62,3 +64,5 @@ TEST_F(MonitoringModeLogStreamTest, MonitoringModeOnLeadsToCorrectString)
     EXPECT_THAT(m_loggerMock.m_logs[0].message, Eq("MonitoringMode::ON"));
     EXPECT_THAT(m_loggerMock.m_logs[0].level, Eq(iox::log::LogLevel::kWarn));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_mq_message.cpp b/iceoryx_posh/test/moduletests/test_mq_message.cpp
index e9bbbc4e26..5d2e832ff0 100644
--- a/iceoryx_posh/test/moduletests/test_mq_message.cpp
+++ b/iceoryx_posh/test/moduletests/test_mq_message.cpp
@@ -20,6 +20,8 @@
 #include "iceoryx_utils/testing/mocks/time_mock.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using iox::runtime::IpcMessage;
@@ -433,4 +435,6 @@ TEST_F(IpcMessage_test, setMessage)
     message1.setMessage("1,2,3,4");
     EXPECT_THAT(message1.isValid(), Eq(false));
 }
+
+} // namespace
 #endif
diff --git a/iceoryx_posh/test/moduletests/test_popo_base_publisher.cpp b/iceoryx_posh/test/moduletests/test_popo_base_publisher.cpp
index d993670b8d..aa8f2a2bcf 100644
--- a/iceoryx_posh/test/moduletests/test_popo_base_publisher.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_base_publisher.cpp
@@ -20,6 +20,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
@@ -109,3 +111,5 @@ TEST_F(BasePublisherTest, DestroysUnderlyingPortOnDestruction)
 {
     EXPECT_CALL(sut.port(), destroy).Times(1);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_chunk_distributor.cpp b/iceoryx_posh/test/moduletests/test_popo_chunk_distributor.cpp
index ea0e07dc93..a37920acbf 100644
--- a/iceoryx_posh/test/moduletests/test_popo_chunk_distributor.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_chunk_distributor.cpp
@@ -28,8 +28,9 @@
 
 #include <memory>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 using namespace iox::popo;
 using namespace iox::cxx;
 using namespace iox::mepoo;
@@ -645,3 +646,5 @@ TYPED_TEST(ChunkDistributor_test, MultipleBlockingQueuesWillBeFilledWhenThereBec
         EXPECT_THAT(this->getSharedChunkValue(*maybeSharedChunk), Eq(1152U));
     }
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_chunk_queue.cpp b/iceoryx_posh/test/moduletests/test_popo_chunk_queue.cpp
index 7e65bbcf84..aabe44255b 100644
--- a/iceoryx_posh/test/moduletests/test_popo_chunk_queue.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_chunk_queue.cpp
@@ -28,8 +28,9 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::popo;
 using namespace iox::mepoo;
@@ -381,3 +382,5 @@ TYPED_TEST(ChunkQueueSoFi_test, LostChunkInfoIsResetAfterRead)
 
     EXPECT_FALSE(this->m_popper.hasLostChunks());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_chunk_receiver.cpp b/iceoryx_posh/test/moduletests/test_popo_chunk_receiver.cpp
index be7268efad..ac81b29787 100644
--- a/iceoryx_posh/test/moduletests/test_popo_chunk_receiver.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_chunk_receiver.cpp
@@ -29,6 +29,8 @@
 
 #include <memory>
 
+namespace
+{
 using namespace ::testing;
 
 struct DummySample
@@ -229,3 +231,5 @@ TEST_F(ChunkReceiver_test, Cleanup)
 
     EXPECT_THAT(m_memoryManager.getMemPoolInfo(0).m_usedChunks, Eq(0U));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_chunk_sender.cpp b/iceoryx_posh/test/moduletests/test_popo_chunk_sender.cpp
index fecfd0e14d..00a5c8e902 100644
--- a/iceoryx_posh/test/moduletests/test_popo_chunk_sender.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_chunk_sender.cpp
@@ -35,6 +35,8 @@
 
 #include <memory>
 
+namespace
+{
 using namespace ::testing;
 
 struct DummySample
@@ -628,3 +630,5 @@ TEST_F(ChunkSender_test, Cleanup)
 
     EXPECT_THAT(m_memoryManager.getMemPoolInfo(0).m_usedChunks, Eq(0U));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_condition_variable.cpp b/iceoryx_posh/test/moduletests/test_popo_condition_variable.cpp
index ff6f1dc0ee..5dce6e7eaa 100644
--- a/iceoryx_posh/test/moduletests/test_popo_condition_variable.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_condition_variable.cpp
@@ -27,8 +27,9 @@
 #include <thread>
 #include <type_traits>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 using namespace iox::popo;
 using namespace iox::cxx;
 using namespace iox::units::duration_literals;
@@ -466,3 +467,5 @@ TEST_F(ConditionVariable_test, TimedWaitReturnsSortedListWhenTriggeredInReverseO
     waitReturnsSortedListWhenTriggeredInReverseOrder(
         *this, [this] { return m_waiter.timedWait(iox::units::Duration::fromSeconds(1)); });
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_listener.cpp b/iceoryx_posh/test/moduletests/test_popo_listener.cpp
index bea8c78165..03e1d55ab5 100644
--- a/iceoryx_posh/test/moduletests/test_popo_listener.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_listener.cpp
@@ -32,8 +32,9 @@
 #include <memory>
 #include <thread>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 using namespace iox::popo;
 using namespace iox::cxx;
 using namespace iox::units::duration_literals;
@@ -1160,3 +1161,4 @@ TIMING_TEST_F(Listener_test, AttachingInCallbackWorks, Repeat(5), [&] {
 // END
 //////////////////////////////////
 
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_notification_info.cpp b/iceoryx_posh/test/moduletests/test_popo_notification_info.cpp
index 6447e7df88..9f70c56a1d 100644
--- a/iceoryx_posh/test/moduletests/test_popo_notification_info.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_notification_info.cpp
@@ -20,6 +20,8 @@
 #include "test.hpp"
 #include <thread>
 
+namespace
+{
 using namespace iox;
 using namespace iox::popo;
 using namespace ::testing;
@@ -125,3 +127,5 @@ TEST_F(NotificationInfo_test, triggerCallbackReturnsFalseWithUnsetCallback)
     m_sut = NotificationInfo{&m_origin, 9U, NotificationCallback<NotificationOriginTest, int>{}};
     EXPECT_FALSE(m_sut());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_publisher.cpp b/iceoryx_posh/test/moduletests/test_popo_publisher.cpp
index 06a8935bb8..c87b7b88eb 100644
--- a/iceoryx_posh/test/moduletests/test_popo_publisher.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_publisher.cpp
@@ -21,13 +21,11 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
-// anonymous namespace to prevent linker issues or sanitizer false positives
-// if a struct with the same name is used in other tests
-namespace
-{
 struct DummyData
 {
     DummyData() = default;
@@ -42,7 +40,6 @@ struct DummyData
     };
     uint64_t val{defaultVal()};
 };
-} // namespace
 
 using TestPublisher = iox::popo::PublisherImpl<DummyData, iox::mepoo::NoUserHeader, MockBasePublisher<DummyData>>;
 
@@ -299,3 +296,5 @@ TEST_F(PublisherTest, GetServiceDescriptionCallForwardedToUnderlyingPublisherPor
     // ===== Test ===== //
     sut.getServiceDescription();
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_publisher_port.cpp b/iceoryx_posh/test/moduletests/test_popo_publisher_port.cpp
index 5a52094dc5..b6d1ae1829 100644
--- a/iceoryx_posh/test/moduletests/test_popo_publisher_port.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_publisher_port.cpp
@@ -31,6 +31,8 @@
 
 #include <memory>
 
+namespace
+{
 using namespace ::testing;
 
 struct DummySample
@@ -550,3 +552,5 @@ TEST_F(PublisherPort_test, cleanupReleasesAllChunks)
 
     EXPECT_THAT(m_memoryManager.getMemPoolInfo(0).m_usedChunks, Eq(0U));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_sample.cpp b/iceoryx_posh/test/moduletests/test_popo_sample.cpp
index 4d44ac4476..69395b2614 100644
--- a/iceoryx_posh/test/moduletests/test_popo_sample.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_sample.cpp
@@ -23,13 +23,11 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
-// anonymous namespace to prevent linker issues or sanitizer false positives
-// if a struct with the same name is used in other tests
-namespace
-{
 struct DummyData
 {
     DummyData() = default;
@@ -40,7 +38,6 @@ struct DummyHeader
     DummyHeader() = default;
     uint64_t counter = 0;
 };
-} // namespace
 
 template <typename T, typename H = iox::mepoo::NoUserHeader>
 class MockPublisherInterface : public iox::popo::PublisherInterface<T, H>
@@ -157,3 +154,5 @@ TEST_F(SampleTest, CallingGetUserHeaderFromConstTypeReturnsCorrectAddress)
 
     // ===== Cleanup ===== //
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_subscriber.cpp b/iceoryx_posh/test/moduletests/test_popo_subscriber.cpp
index a9354551ab..6a995be896 100644
--- a/iceoryx_posh/test/moduletests/test_popo_subscriber.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_subscriber.cpp
@@ -21,18 +21,15 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
-// anonymous namespace to prevent linker issues or sanitizer false positives
-// if a struct with the same name is used in other tests
-namespace
-{
 struct DummyData
 {
     uint64_t val = 42;
 };
-} // namespace
 
 template <typename T, typename H, typename BaseSubscriber>
 class StubbedSubscriber : public iox::popo::SubscriberImpl<T, H, BaseSubscriber>
@@ -181,3 +178,5 @@ TEST_F(SubscriberTest, ReleasesQueuedDataViaBaseSubscriber)
     // ===== Verify ===== //
     // ===== Cleanup ===== //
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_subscriber_port.cpp b/iceoryx_posh/test/moduletests/test_popo_subscriber_port.cpp
index 163a72c4f2..ed8ef9645b 100644
--- a/iceoryx_posh/test/moduletests/test_popo_subscriber_port.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_subscriber_port.cpp
@@ -32,6 +32,8 @@
 
 #include <memory>
 
+namespace
+{
 using namespace ::testing;
 
 class SubscriberPortSingleProducer_test : public Test
@@ -521,3 +523,5 @@ TEST_F(SubscriberPortMultiProducer_test, InvalidMessageResultsInError)
     EXPECT_TRUE(errorHandlerCalled);
     ASSERT_THAT(receivedError, Eq(iox::Error::kPOPO__CAPRO_PROTOCOL_ERROR));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_toml_gateway_config_parser.cpp b/iceoryx_posh/test/moduletests/test_popo_toml_gateway_config_parser.cpp
index 78ae65563d..02215f075d 100644
--- a/iceoryx_posh/test/moduletests/test_popo_toml_gateway_config_parser.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_toml_gateway_config_parser.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2020 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -14,12 +15,14 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
+#include "iceoryx/tests/posh/moduletests/test_input_path.hpp"
 #include "iceoryx_posh/gateway/toml_gateway_config_parser.hpp"
 #include "stubs/stub_toml_gateway_config_parser.hpp"
 
 #include "test.hpp"
-#include "iceoryx/tests/posh/moduletests/test_input_path.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
@@ -255,3 +258,5 @@ TEST_P(TomlGatewayConfigParserTest, ParseMalformedInputFileCausesError)
     ASSERT_TRUE(result.has_error());
     EXPECT_EQ(parseErrorInputFile.first, result.get_error());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_trigger.cpp b/iceoryx_posh/test/moduletests/test_popo_trigger.cpp
index 81e837d4fe..c8ecb3153f 100644
--- a/iceoryx_posh/test/moduletests/test_popo_trigger.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_trigger.cpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2020, 2021 by Apex.AI Inc. All rights reserved.
+// Copyright (c) 2020 - 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -20,6 +20,8 @@
 #include "test.hpp"
 #include <thread>
 
+namespace
+{
 using namespace iox;
 using namespace iox::popo;
 using namespace ::testing;
@@ -767,3 +769,5 @@ TEST_F(Trigger_test, EventBasedMovedAssignedWithInvalidTrigger)
     EXPECT_THAT(trigger.getTriggerType(), Eq(TriggerType::INVALID));
     EXPECT_FALSE(trigger.isLogicalEqualTo(&m_triggerClass, anotherOriginType, anotherOriginTypeHash));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_trigger_handle.cpp b/iceoryx_posh/test/moduletests/test_popo_trigger_handle.cpp
index 4dc9889536..9cdbad3423 100644
--- a/iceoryx_posh/test/moduletests/test_popo_trigger_handle.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_trigger_handle.cpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2020, 2021 by Apex.AI Inc. All rights reserved.
+// Copyright (c) 2020 - 2021 by Apex.AI Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -22,6 +22,8 @@
 #include "test.hpp"
 #include <thread>
 
+namespace
+{
 using namespace iox;
 using namespace iox::popo;
 using namespace ::testing;
@@ -149,3 +151,4 @@ TEST_F(TriggerHandle_test, wasTriggeredReturnsFalseAfterItWasTriggeredAndTheList
     EXPECT_FALSE(m_sut.wasTriggered());
 }
 
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_typed_unique_id.cpp b/iceoryx_posh/test/moduletests/test_popo_typed_unique_id.cpp
index 05eed0bdfe..0471ccaf63 100644
--- a/iceoryx_posh/test/moduletests/test_popo_typed_unique_id.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_typed_unique_id.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2020 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,7 +20,8 @@
 #include "iceoryx_utils/cxx/generic_raii.hpp"
 #include "test.hpp"
 
-
+namespace
+{
 using namespace ::testing;
 using namespace iox::popo;
 using namespace iox::cxx;
@@ -167,3 +169,5 @@ TYPED_TEST(TypedUniqueId_test, InvalidIdIsInvalid)
     typename TestFixture::UniqueIDType a(InvalidId);
     EXPECT_FALSE(a.isValid());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_untyped_subscriber.cpp b/iceoryx_posh/test/moduletests/test_popo_untyped_subscriber.cpp
index 68eea5444f..044cddff65 100644
--- a/iceoryx_posh/test/moduletests/test_popo_untyped_subscriber.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_untyped_subscriber.cpp
@@ -21,18 +21,15 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using ::testing::_;
 
-// anonymous namespace to prevent linker issues or sanitizer false positives
-// if a struct with the same name is used in other tests
-namespace
-{
 struct DummyData
 {
     uint64_t val = 42;
 };
-} // namespace
 
 using TestUntypedSubscriber = iox::popo::UntypedSubscriberImpl<MockBaseSubscriber<void>>;
 
@@ -151,3 +148,5 @@ TEST_F(UntypedSubscriberTest, ReleasesQueuedDataViaBaseSubscriber)
     // ===== Verify ===== //
     // ===== Cleanup ===== //
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_user_trigger.cpp b/iceoryx_posh/test/moduletests/test_popo_user_trigger.cpp
index d78918fcdc..d233352adb 100644
--- a/iceoryx_posh/test/moduletests/test_popo_user_trigger.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_user_trigger.cpp
@@ -21,12 +21,12 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox;
 using namespace iox::popo;
 
-namespace
-{
 class WaitSetTest : public iox::popo::WaitSet<>
 {
   public:
@@ -56,7 +56,6 @@ class UserTrigger_test : public Test
         m_callbackOrigin = origin;
     }
 };
-} // namespace
 
 UserTrigger* UserTrigger_test::m_callbackOrigin = nullptr;
 
@@ -189,3 +188,5 @@ TEST_F(UserTrigger_test, UserTriggerCallbackCanBeCalledOverloadWithoutId)
     (*triggerInfoVector[0U])();
     EXPECT_THAT(m_callbackOrigin, &sut);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_popo_waitset.cpp b/iceoryx_posh/test/moduletests/test_popo_waitset.cpp
index 89f1f34183..8975900fd7 100644
--- a/iceoryx_posh/test/moduletests/test_popo_waitset.cpp
+++ b/iceoryx_posh/test/moduletests/test_popo_waitset.cpp
@@ -29,14 +29,13 @@
 #include <memory>
 #include <thread>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 using namespace iox::popo;
 using namespace iox::cxx;
 using namespace iox::units::duration_literals;
 
-namespace
-{
 class WaitSetTest : public iox::popo::WaitSet<>
 {
   public:
@@ -396,7 +395,6 @@ SimpleState1 WaitSet_test::SimpleEventClass::m_simpleState1 = SimpleState1::INVA
 SimpleState2 WaitSet_test::SimpleEventClass::m_simpleState2 = SimpleState2::INVALID;
 SimpleState1 WaitSet_test::SimpleEventClass::m_simpleState1TriggerCallback = SimpleState1::INVALID;
 SimpleState2 WaitSet_test::SimpleEventClass::m_simpleState2TriggerCallback = SimpleState2::INVALID;
-} // namespace
 
 ////////////////////////
 // BEGIN attach / detach
@@ -1460,3 +1458,4 @@ TEST_F(WaitSet_test, TimedWaitUnblocksAfterMarkForDestructionCall)
     t.join();
 }
 
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_posh_modules.cpp b/iceoryx_posh/test/moduletests/test_posh_modules.cpp
index 2581448004..5393ec26ad 100644
--- a/iceoryx_posh/test/moduletests/test_posh_modules.cpp
+++ b/iceoryx_posh/test/moduletests/test_posh_modules.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,7 +19,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 
 int main(int argc, char* argv[])
diff --git a/iceoryx_posh/test/moduletests/test_posh_runtime.cpp b/iceoryx_posh/test/moduletests/test_posh_runtime.cpp
index c706e94d49..08fbb0655d 100644
--- a/iceoryx_posh/test/moduletests/test_posh_runtime.cpp
+++ b/iceoryx_posh/test/moduletests/test_posh_runtime.cpp
@@ -26,6 +26,8 @@
 
 #include <type_traits>
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::runtime;
 using iox::roudi::RouDiEnvironment;
@@ -53,15 +55,12 @@ class PoshRuntimeTestAccess : public PoshRuntime
     }
 };
 
-namespace
-{
 bool callbackWasCalled = false;
 PoshRuntime& testFactory(iox::cxx::optional<const iox::RuntimeName_t*> name)
 {
     callbackWasCalled = true;
     return PoshRuntimeTestAccess::getDefaultRuntime(name);
 }
-} // namespace
 
 class PoshRuntime_test : public Test
 {
@@ -101,12 +100,8 @@ class PoshRuntime_test : public Test
     IpcMessage m_receiveBuffer;
     const iox::NodeName_t m_nodeName{"testNode"};
     const iox::NodeName_t m_invalidNodeName{"invalidNode,"};
-    static bool m_errorHandlerCalled;
 };
 
-bool PoshRuntime_test::m_errorHandlerCalled{false};
-
-
 TEST_F(PoshRuntime_test, ValidAppName)
 {
     iox::RuntimeName_t appName("valid_name");
@@ -740,3 +735,5 @@ TEST(PoshRuntimeFactory_test, DISABLED_SetEmptyRuntimeFactoryFails)
     // just in case the previous test doesn't die and breaks the following tests
     PoshRuntimeTestAccess::resetRuntimeFactory();
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_posh_runtime_node.cpp b/iceoryx_posh/test/moduletests/test_posh_runtime_node.cpp
index 47a28ec186..ff57600969 100644
--- a/iceoryx_posh/test/moduletests/test_posh_runtime_node.cpp
+++ b/iceoryx_posh/test/moduletests/test_posh_runtime_node.cpp
@@ -21,15 +21,13 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::runtime;
 using namespace iox::roudi;
+using namespace iox;
 
-
-namespace iox
-{
-namespace test
-{
 /// @brief Test goal: This test suit verifies class node
 
 class PoshRuntimeNode_test : public Test
@@ -112,5 +110,4 @@ TEST_F(PoshRuntimeNode_test, VerifyMoveConstructorAssignsCorrectNodeName)
     EXPECT_THAT(nodeTest.getNodeName(), Eq(nodeNewName));
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_posh_runtime_node_property.cpp b/iceoryx_posh/test/moduletests/test_posh_runtime_node_property.cpp
index 1366461e18..38361b36a5 100644
--- a/iceoryx_posh/test/moduletests/test_posh_runtime_node_property.cpp
+++ b/iceoryx_posh/test/moduletests/test_posh_runtime_node_property.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2021 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,15 +20,13 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::runtime;
 using namespace iox::roudi;
+using namespace iox;
 
-
-namespace iox
-{
-namespace test
-{
 /// @brief Test goal: This test suit verifies class node
 
 class PoshRuntimeNodeProperty_test : public Test
@@ -77,5 +76,4 @@ TEST_F(PoshRuntimeNodeProperty_test, ConstructorNodePropertyWithWrongSerializati
     EXPECT_EQ(sut.m_name, nodeName);
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_posh_runtime_single_process.cpp b/iceoryx_posh/test/moduletests/test_posh_runtime_single_process.cpp
index 519a7f206f..2f66fd9afe 100644
--- a/iceoryx_posh/test/moduletests/test_posh_runtime_single_process.cpp
+++ b/iceoryx_posh/test/moduletests/test_posh_runtime_single_process.cpp
@@ -20,14 +20,13 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::runtime;
 using namespace iox::roudi;
+using namespace iox;
 
-namespace iox
-{
-namespace test
-{
 /// @brief Test goal: This test suit verifies class posh_runtime_single_process
 
 class PoshRuntimeSingleProcess_test : public Test
@@ -79,5 +78,4 @@ TEST_F(PoshRuntimeSingleProcess_test, ConstructorPoshRuntimeSingleProcessMultipl
     EXPECT_THAT(detectedError.value(), Eq(iox::Error::kPOSH__RUNTIME_IS_CREATED_MULTIPLE_TIMES));
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser.cpp b/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser.cpp
index 8fafa10fd2..9ee9b05888 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser.cpp
@@ -21,7 +21,6 @@
 #include "iceoryx_posh/roudi/roudi_cmd_line_parser.hpp"
 
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::roudi;
 using namespace iox::config;
@@ -43,9 +42,7 @@ bool operator==(const CmdLineArgs_t& lhs, const CmdLineArgs_t& rhs)
 } // namespace config
 } // namespace iox
 
-namespace iox
-{
-namespace test
+namespace
 {
 class CmdLineParser_test : public Test
 {
@@ -475,6 +472,5 @@ TEST_F(CmdLineParser_test, CmdLineParsingModeEqualToOneHandlesOnlyTheFirstOption
     EXPECT_TRUE(result.value().run);
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
 #endif
diff --git a/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser_config_file_option.cpp b/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser_config_file_option.cpp
index 9abac58e31..85d39cca49 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser_config_file_option.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_cmd_line_parser_config_file_option.cpp
@@ -23,16 +23,13 @@
 
 #include <memory>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using namespace iox::cxx;
 using namespace iox::config;
 
-namespace iox
-{
-namespace test
-{
 class CmdLineParserConfigFileOption_test : public Test
 {
   public:
@@ -178,7 +175,6 @@ TEST_F(CmdLineParserConfigFileOption_test, CmdLineParsingModeEqualToOneHandleOnl
     EXPECT_THAT(res.value().configFilePath.c_str(), StrEq(path));
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
 
 #endif
diff --git a/iceoryx_posh/test/moduletests/test_roudi_config_toml_file_provider.cpp b/iceoryx_posh/test/moduletests/test_roudi_config_toml_file_provider.cpp
index 313d08c7fe..abbfe536a2 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_config_toml_file_provider.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_config_toml_file_provider.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2021 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,12 +20,11 @@
 #include "iceoryx/tests/posh/moduletests/test_input_path.hpp"
 #include "test.hpp"
 
-using namespace ::testing;
-
 namespace
 {
+using namespace ::testing;
+
 using ParseErrorInputFile_t = std::pair<iox::roudi::RouDiConfigFileParseError, iox::roudi::ConfigFilePathString_t>;
-};
 
 class RoudiConfigTomlFileProvider_test : public TestWithParam<ParseErrorInputFile_t>
 {
@@ -93,3 +93,5 @@ TEST_P(RoudiConfigTomlFileProvider_test, ParseMalformedInputFileCausesError)
     ASSERT_TRUE(result.has_error());
     EXPECT_EQ(parseErrorInputFile.first, result.get_error());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_generic_memory_block.cpp b/iceoryx_posh/test/moduletests/test_roudi_generic_memory_block.cpp
index 017406e246..c882a130aa 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_generic_memory_block.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_generic_memory_block.cpp
@@ -21,6 +21,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::roudi;
@@ -219,3 +221,5 @@ TEST_F(GenericMemoryBlock_NonTrivial_Test, RepetitiveDestroyWithEmplace)
 
     EXPECT_THAT(NonTrivialClass::s_destructorCounter, Eq(1u));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_iceoryx_roudi_app.cpp b/iceoryx_posh/test/moduletests/test_roudi_iceoryx_roudi_app.cpp
index 79bf53864f..93f1421dfb 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_iceoryx_roudi_app.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_iceoryx_roudi_app.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2021 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -24,16 +25,14 @@
 
 #include <regex>
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using iox::roudi::IceOryxRouDiApp;
 using namespace iox::config;
+using namespace iox;
 
-namespace iox
-{
-namespace test
-{
 class OutputBuffer
 {
   public:
@@ -271,5 +270,4 @@ TEST_F(IceoryxRoudiApp_test, VerifyConstructorUsingConfigWithSegmentWithoutMemPo
     EXPECT_NE(output.find(expected), std::string::npos);
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_iceoyx_roudi_memory_manager.cpp b/iceoryx_posh/test/moduletests/test_roudi_iceoyx_roudi_memory_manager.cpp
index d0859de60b..770d1ccf84 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_iceoyx_roudi_memory_manager.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_iceoyx_roudi_memory_manager.cpp
@@ -19,14 +19,12 @@
 
 #include "iceoryx_posh/roudi/memory/iceoryx_roudi_memory_manager.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using iox::roudi::IceOryxRouDiMemoryManager;
 
-namespace iox
-{
-namespace test
-{
 /// @brief This test file verifies that the BaseClass IceoryxRouDiMemoryManager is tested
 class IceoryxRoudiMemoryManager_test : public Test
 {
@@ -167,5 +165,4 @@ TEST_F(IceoryxRoudiMemoryManager_test, DestroyMemoryNotFailingAfterCalledTwoTime
     EXPECT_THAT(res.has_error(), Eq(false));
 }
 
-} // namespace test
-} // namespace iox
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_memory_block.cpp b/iceoryx_posh/test/moduletests/test_roudi_memory_block.cpp
index 35dfc5805e..2fd0adda9e 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_memory_block.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_memory_block.cpp
@@ -22,6 +22,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::roudi;
@@ -59,3 +61,5 @@ TEST_F(MemoryBlock_Test, MemoryAvailableAfterCreation)
     ASSERT_THAT(sut.memory().has_value(), Eq(true));
     EXPECT_THAT(sut.memory().value(), Eq(memoryProvider.dummyMemory));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_memory_manager.cpp b/iceoryx_posh/test/moduletests/test_roudi_memory_manager.cpp
index b9ed3f2f8e..68663780ef 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_memory_manager.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_memory_manager.cpp
@@ -23,6 +23,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::roudi;
@@ -151,3 +153,5 @@ TEST_F(RouDiMemoryManager_Test, OperatorTest)
         EXPECT_THAT(loggerMock.m_logs[i].message, Eq(m_testResultOperatorMethod[i]));
     }
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_memory_provider.cpp b/iceoryx_posh/test/moduletests/test_roudi_memory_provider.cpp
index 02c28acd76..de7e597ae9 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_memory_provider.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_memory_provider.cpp
@@ -24,6 +24,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::roudi;
@@ -347,3 +349,5 @@ TEST_F(MemoryProvider_Test, GetErrorString)
         EXPECT_THAT(*result, Eq(*m_testResultGetErrorString[i]));
     }
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_mempool_introspection.cpp b/iceoryx_posh/test/moduletests/test_roudi_mempool_introspection.cpp
index 1c4bb7ea08..21ceb02146 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_mempool_introspection.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_mempool_introspection.cpp
@@ -15,21 +15,19 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
+#include "iceoryx_posh/internal/mepoo/segment_manager.hpp"
+#include "iceoryx_posh/internal/roudi/introspection/mempool_introspection.hpp"
+#include "iceoryx_posh/roudi/introspection_types.hpp"
 #include "iceoryx_posh/testing/mocks/chunk_mock.hpp"
+#include "iceoryx_utils/cxx/vector.hpp"
+#include "iceoryx_utils/testing/timing_test.hpp"
 #include "mocks/mepoo_memory_manager_mock.hpp"
 #include "mocks/publisher_mock.hpp"
-#include "iceoryx_utils/testing/timing_test.hpp"
-#include "test.hpp"
-
-using namespace ::testing;
-using ::testing::Return;
 
-#include "iceoryx_posh/internal/roudi/introspection/mempool_introspection.hpp"
-
-#include "iceoryx_posh/internal/mepoo/segment_manager.hpp"
-#include "iceoryx_posh/roudi/introspection_types.hpp"
-#include "iceoryx_utils/cxx/vector.hpp"
+#include "test.hpp"
 
+namespace
+{
 class CallChecker
 {
   public:
@@ -274,3 +272,5 @@ TIMING_TEST_F(MemPoolIntrospection_test, thread, Repeat(5), [&] {
         6 * snapshotInterval.toMilliseconds())); // the thread should sleep, if not, we have 12 runs
     introspectionAccess.stop();
 });
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_port_introspection.cpp b/iceoryx_posh/test/moduletests/test_roudi_port_introspection.cpp
index ec0917c19e..8d7f1410c8 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_port_introspection.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_port_introspection.cpp
@@ -15,20 +15,21 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
+#include "iceoryx_posh/internal/roudi/introspection/port_introspection.hpp"
+#include "iceoryx_posh/mepoo/chunk_header.hpp"
 #include "iceoryx_posh/testing/mocks/chunk_mock.hpp"
 #include "iceoryx_utils/cxx/generic_raii.hpp"
 #include "mocks/publisher_mock.hpp"
 #include "mocks/subscriber_mock.hpp"
-#include "test.hpp"
 
-using namespace ::testing;
-using ::testing::Return;
-
-#include "iceoryx_posh/internal/roudi/introspection/port_introspection.hpp"
-#include "iceoryx_posh/mepoo/chunk_header.hpp"
+#include "test.hpp"
 
 #include <cstdint>
 
+namespace
+{
+using namespace ::testing;
+
 template <typename PublisherPort, typename SubscriberPort>
 class PortIntrospectionAccess : public iox::roudi::PortIntrospection<PublisherPort, SubscriberPort>
 {
@@ -471,3 +472,5 @@ TEST_F(PortIntrospection_test, DISABLED_thread)
     std::this_thread::sleep_for(
         std::chrono::milliseconds(555)); // if the thread doesn't stop, we have 12 runs after the sleep period
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_portmanager.cpp b/iceoryx_posh/test/moduletests/test_roudi_portmanager.cpp
index 843b07bae7..173d694548 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_portmanager.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_portmanager.cpp
@@ -15,12 +15,9 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-#include "test.hpp"
-
-#include "iceoryx_posh/internal/capro/capro_message.hpp"
-#include "iceoryx_posh/internal/popo/ports/publisher_port_user.hpp"
 
 #include "iceoryx_posh/iceoryx_posh_types.hpp"
+#include "iceoryx_posh/internal/capro/capro_message.hpp"
 #include "iceoryx_posh/internal/popo/ports/publisher_port_user.hpp"
 #include "iceoryx_posh/internal/roudi/port_manager.hpp"
 #include "iceoryx_posh/roudi/memory/iceoryx_roudi_memory_manager.hpp"
@@ -28,14 +25,16 @@
 #include "iceoryx_utils/cxx/generic_raii.hpp"
 #include "iceoryx_utils/internal/relocatable_pointer/base_relative_pointer.hpp"
 #include "iceoryx_utils/posix_wrapper/posix_access_rights.hpp"
-
 #include "iceoryx_utils/testing/watch_dog.hpp"
 
+#include "test.hpp"
+
 #include <cstdint>
 #include <limits> // std::numeric_limits
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 using iox::popo::PublisherOptions;
 using iox::popo::PublisherPortUser;
@@ -84,7 +83,8 @@ class PortManager_test : public Test
         m_portManager = new PortManagerTester(m_roudiMemoryManager);
 
         auto user = iox::posix::PosixUser::getUserOfCurrentProcess().getName();
-        auto segmentInfo = m_roudiMemoryManager->segmentManager().value()->getSegmentInformationWithWriteAccessForUser(user);
+        auto segmentInfo =
+            m_roudiMemoryManager->segmentManager().value()->getSegmentInformationWithWriteAccessForUser(user);
         ASSERT_TRUE(segmentInfo.m_memoryManager.has_value());
 
         m_payloadDataSegmentMemoryManager = &segmentInfo.m_memoryManager.value().get();
@@ -1034,3 +1034,5 @@ TEST_F(PortManager_test, OfferPublisherServiceUpdatesServiceRegistryChangeCounte
 
     EXPECT_EQ(serviceCounter->load(), initialCount + 1);
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_portpool.cpp b/iceoryx_posh/test/moduletests/test_roudi_portpool.cpp
index 0de1f5f25b..2c1122809a 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_portpool.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_portpool.cpp
@@ -22,14 +22,12 @@
 #include "iceoryx_utils/cxx/convert.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 using namespace iox::capro;
+using namespace iox;
 
-namespace iox
-{
-namespace test
-{
 static constexpr uint32_t DEFAULT_DEVICE_ID{20U};
 static constexpr uint32_t DEFAULT_MEMORY_TYPE{100U};
 class PortPool_test : public Test
@@ -615,5 +613,5 @@ TEST_F(PortPool_test, GetServiceRegistryChangeCounterIsSuccessful)
 
     ASSERT_EQ(serviceCounter->load(), 1U);
 }
-} // namespace test
-} // namespace iox
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_posix_shm_memory_provider.cpp b/iceoryx_posh/test/moduletests/test_roudi_posix_shm_memory_provider.cpp
index a3f39e09b0..84fb23cb42 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_posix_shm_memory_provider.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_posix_shm_memory_provider.cpp
@@ -23,6 +23,8 @@
 
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 
 using namespace iox::roudi;
@@ -110,3 +112,5 @@ TEST_F(PosixShmMemoryProvider_Test, CreationFailedWithAlignmentExceedingPageSize
 
     EXPECT_THAT(shmExists(), Eq(false));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_process.cpp b/iceoryx_posh/test/moduletests/test_roudi_process.cpp
index fea14f679a..bc96b1e8ee 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_process.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_process.cpp
@@ -24,12 +24,13 @@
 #include "iceoryx_utils/platform/types.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::roudi;
 using namespace iox::popo;
 using namespace iox::runtime;
 using namespace iox::posix;
-using ::testing::Return;
 
 class IpcInterfaceUser_Mock : public iox::roudi::Process
 {
@@ -110,3 +111,5 @@ TEST_F(Process_test, TimeStamp)
     roudiproc.setTimestamp(timestmp);
     EXPECT_THAT(roudiproc.getTimestamp(), Eq(timestmp));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_process_introspection.cpp b/iceoryx_posh/test/moduletests/test_roudi_process_introspection.cpp
index acc37d2b03..f23240542f 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_process_introspection.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_process_introspection.cpp
@@ -15,17 +15,17 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
+#include "iceoryx_posh/internal/popo/ports/publisher_port_data.hpp"
+#include "iceoryx_posh/internal/roudi/introspection/process_introspection.hpp"
+#include "iceoryx_posh/testing/mocks/chunk_mock.hpp"
 #include "iceoryx_utils/testing/timing_test.hpp"
+#include "mocks/publisher_mock.hpp"
+
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
-
-#include "iceoryx_posh/internal/roudi/introspection/process_introspection.hpp"
-
-#include "iceoryx_posh/internal/popo/ports/publisher_port_data.hpp"
-#include "iceoryx_posh/testing/mocks/chunk_mock.hpp"
-#include "mocks/publisher_mock.hpp"
 
 class ProcessIntrospectionAccess : public iox::roudi::ProcessIntrospection<MockPublisherPortUser>
 {
@@ -264,3 +264,5 @@ TEST_F(ProcessIntrospection_test, addRemoveNode)
         EXPECT_CALL(introspectionAccess.getPublisherPort().value(), stopOffer()).Times(1);
     }
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_process_manager.cpp b/iceoryx_posh/test/moduletests/test_roudi_process_manager.cpp
index 7940eddbcd..da571741b1 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_process_manager.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_process_manager.cpp
@@ -26,13 +26,14 @@
 #include "iceoryx_utils/testing/watch_dog.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::roudi;
 using namespace iox::popo;
 using namespace iox::runtime;
 using namespace iox::posix;
 using namespace iox::version;
-using ::testing::Return;
 
 class ProcessManager_test : public Test
 {
@@ -147,3 +148,5 @@ TEST_F(ProcessManager_test, HandleProcessShutdownPreparationRequestWorks)
     // ideally this should be checked by a mock, but since there isn't on for PortManager we just check the side effect
     ASSERT_FALSE(publisher.isOffered());
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_roudi_service_registry.cpp b/iceoryx_posh/test/moduletests/test_roudi_service_registry.cpp
index f8c885cb95..e3c9ea053f 100644
--- a/iceoryx_posh/test/moduletests/test_roudi_service_registry.cpp
+++ b/iceoryx_posh/test/moduletests/test_roudi_service_registry.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -14,13 +15,14 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-#include "test.hpp"
-
 #include "iceoryx_posh/internal/roudi/service_registry.hpp"
 #include "iceoryx_utils/cxx/string.hpp"
 
+#include "test.hpp"
+
+namespace
+{
 using namespace ::testing;
-using ::testing::Return;
 
 class ServiceRegistry_test : public Test
 {
@@ -187,3 +189,5 @@ TEST_F(ServiceRegistry_test, GetServiceMap)
 
     EXPECT_THAT(mapA && mapE, Eq(true));
 }
+
+} // namespace
diff --git a/iceoryx_posh/test/moduletests/test_runtime_ipc_interface_creator.cpp b/iceoryx_posh/test/moduletests/test_runtime_ipc_interface_creator.cpp
index 3f8439b62d..6ee1df08ec 100644
--- a/iceoryx_posh/test/moduletests/test_runtime_ipc_interface_creator.cpp
+++ b/iceoryx_posh/test/moduletests/test_runtime_ipc_interface_creator.cpp
@@ -21,6 +21,8 @@
 
 #include <chrono>
 
+namespace
+{
 using namespace ::testing;
 using namespace iox;
 using namespace iox::posix;
@@ -66,4 +68,6 @@ TEST_F(IpcInterfaceCreator_test, CreateWithSameNameLeadsToError)
     EXPECT_DEATH({ IpcInterfaceCreator m_sut2{goodName}; }, ".*");
 }
 
+} // namespace
+
 #endif
diff --git a/iceoryx_posh/test/moduletests/test_version_info.cpp b/iceoryx_posh/test/moduletests/test_version_info.cpp
index 0616b4f3b3..a8c99fc739 100644
--- a/iceoryx_posh/test/moduletests/test_version_info.cpp
+++ b/iceoryx_posh/test/moduletests/test_version_info.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2020 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,6 +19,8 @@
 #include "iceoryx_versions.hpp"
 #include "test.hpp"
 
+namespace
+{
 using namespace ::testing;
 using namespace iox::version;
 using namespace iox::cxx;
@@ -177,3 +180,5 @@ TEST_F(VersionInfo_test, ComparesVersionsDifferInBuildDate)
     EXPECT_TRUE(versionInfo.checkCompatibility(versionInfoWithUnequalBuildDate, CompatibilityCheckLevel::COMMIT_ID));
     EXPECT_FALSE(versionInfo.checkCompatibility(versionInfoWithUnequalBuildDate, CompatibilityCheckLevel::BUILD_DATE));
 }
+
+} // namespace
diff --git a/iceoryx_posh/testing/include/iceoryx_posh/testing/roudi_gtest.hpp b/iceoryx_posh/testing/include/iceoryx_posh/testing/roudi_gtest.hpp
index 87562a2297..bcd812fc19 100644
--- a/iceoryx_posh/testing/include/iceoryx_posh/testing/roudi_gtest.hpp
+++ b/iceoryx_posh/testing/include/iceoryx_posh/testing/roudi_gtest.hpp
@@ -23,7 +23,6 @@
 #include <gtest/gtest.h>
 
 using namespace ::testing;
-using ::testing::Return;
 
 class RouDi_GTest : public iox::roudi::RouDiEnvironment, public Test
 {
diff --git a/iceoryx_utils/test/integrationtests/test_utils_integration.cpp b/iceoryx_utils/test/integrationtests/test_utils_integration.cpp
index d6a24275a2..77fe11c888 100644
--- a/iceoryx_utils/test/integrationtests/test_utils_integration.cpp
+++ b/iceoryx_utils/test/integrationtests/test_utils_integration.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,7 +19,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 int main(int argc, char* argv[])
 {
diff --git a/iceoryx_utils/test/moduletests/test_utils_modules.cpp b/iceoryx_utils/test/moduletests/test_utils_modules.cpp
index 5674cae918..839a773770 100644
--- a/iceoryx_utils/test/moduletests/test_utils_modules.cpp
+++ b/iceoryx_utils/test/moduletests/test_utils_modules.cpp
@@ -1,4 +1,5 @@
 // Copyright (c) 2019 by Robert Bosch GmbH. All rights reserved.
+// Copyright (c) 2021 by Apex.AI inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,7 +19,6 @@
 
 using namespace ::testing;
 using ::testing::_;
-using ::testing::Return;
 
 // global argc and argv needed by the argv_inspection test
 int g_argc;
diff --git a/iceoryx_utils/testing/include/iceoryx_utils/testing/mocks/time_mock.hpp b/iceoryx_utils/testing/include/iceoryx_utils/testing/mocks/time_mock.hpp
index 45639ce51a..00293fbaa8 100644
--- a/iceoryx_utils/testing/include/iceoryx_utils/testing/mocks/time_mock.hpp
+++ b/iceoryx_utils/testing/include/iceoryx_utils/testing/mocks/time_mock.hpp
@@ -23,7 +23,6 @@
 #include <time.h>
 
 using namespace ::testing;
-using ::testing::Return;
 
 class time_MOCK
 {