diff --git a/src/armnnTestUtils/MockBackend.cpp b/src/armnnTestUtils/MockBackend.cpp
index 7441d0c..d954595 100644
--- a/src/armnnTestUtils/MockBackend.cpp
+++ b/src/armnnTestUtils/MockBackend.cpp
@@ -11,6 +11,8 @@
 #include <backendsCommon/test/MockBackendId.hpp>
 #include <SubgraphViewSelector.hpp>
 
+#include "Layer.hpp"
+
 namespace armnn
 {
 
@@ -301,4 +303,4 @@
     return std::make_unique<DefaultAllocator>();
 }
 
-}    // namespace armnn
\ No newline at end of file
+}    // namespace armnn
diff --git a/src/backends/backendsCommon/IBackendInternal.cpp b/src/backends/backendsCommon/IBackendInternal.cpp
index ec1313d..4ce41fe 100644
--- a/src/backends/backendsCommon/IBackendInternal.cpp
+++ b/src/backends/backendsCommon/IBackendInternal.cpp
@@ -5,6 +5,7 @@
 
 #include <armnn/BackendOptions.hpp>
 #include <armnn/backends/IBackendInternal.hpp>
+#include <armnn/backends/WorkloadFactory.hpp>
 
 namespace armnn
 {
diff --git a/src/backends/backendsCommon/test/TestDynamicBackend.cpp b/src/backends/backendsCommon/test/TestDynamicBackend.cpp
index 5018b44..b7c9b4f 100644
--- a/src/backends/backendsCommon/test/TestDynamicBackend.cpp
+++ b/src/backends/backendsCommon/test/TestDynamicBackend.cpp
@@ -6,7 +6,7 @@
 #include "TestDynamicBackend.hpp"
 
 #include <armnn/backends/IBackendInternal.hpp>
-
+#include <armnn/backends/WorkloadFactory.hpp>
 #include <armnn/utility/IgnoreUnused.hpp>
 
 constexpr const char* TestDynamicBackendId()
diff --git a/src/backends/backendsCommon/test/mockBackend/MockImportBackend.hpp b/src/backends/backendsCommon/test/mockBackend/MockImportBackend.hpp
index c07a97c..ff1d691 100644
--- a/src/backends/backendsCommon/test/mockBackend/MockImportBackend.hpp
+++ b/src/backends/backendsCommon/test/mockBackend/MockImportBackend.hpp
@@ -5,6 +5,7 @@
 #pragma once
 
 #include <armnn/backends/IBackendInternal.hpp>
+#include <armnn/utility/PolymorphicDowncast.hpp>
 
 namespace armnn
 {
diff --git a/src/backends/cl/test/ClBackendTests.cpp b/src/backends/cl/test/ClBackendTests.cpp
index 33f3216..e9614a7 100644
--- a/src/backends/cl/test/ClBackendTests.cpp
+++ b/src/backends/cl/test/ClBackendTests.cpp
@@ -3,6 +3,7 @@
 // SPDX-License-Identifier: MIT
 //
 
+#include <backendsCommon/TensorHandleFactoryRegistry.hpp>
 #include <cl/ClBackend.hpp>
 #include <cl/ClTensorHandleFactory.hpp>
 #include <cl/ClImportTensorHandleFactory.hpp>
diff --git a/src/backends/neon/test/NeonBackendTests.cpp b/src/backends/neon/test/NeonBackendTests.cpp
index 23f58a7..562a45e 100644
--- a/src/backends/neon/test/NeonBackendTests.cpp
+++ b/src/backends/neon/test/NeonBackendTests.cpp
@@ -3,6 +3,7 @@
 // SPDX-License-Identifier: MIT
 //
 
+#include <backendsCommon/TensorHandleFactoryRegistry.hpp>
 #include <neon/NeonBackend.hpp>
 #include <neon/NeonTensorHandleFactory.hpp>
 
diff --git a/src/backends/reference/test/RefBackendTests.cpp b/src/backends/reference/test/RefBackendTests.cpp
index 5154ea4..4d55adf 100644
--- a/src/backends/reference/test/RefBackendTests.cpp
+++ b/src/backends/reference/test/RefBackendTests.cpp
@@ -3,9 +3,11 @@
 // SPDX-License-Identifier: MIT
 //
 
+#include <backendsCommon/TensorHandleFactoryRegistry.hpp>
 #include <reference/RefBackend.hpp>
 #include <reference/RefTensorHandleFactory.hpp>
 
+#include <armnn/backends/WorkloadFactory.hpp>
 #include <doctest/doctest.h>
 
 using namespace armnn;