diff --git a/src/backends/backendsCommon/BackendRegistry.hpp b/src/backends/backendsCommon/BackendRegistry.hpp
index 2a52e24..82e59d9 100644
--- a/src/backends/backendsCommon/BackendRegistry.hpp
+++ b/src/backends/backendsCommon/BackendRegistry.hpp
@@ -9,6 +9,7 @@
 
 #include <memory>
 #include <unordered_map>
+#include <functional>
 
 namespace armnn
 {
@@ -57,4 +58,4 @@
 
 BackendRegistry& BackendRegistryInstance();
 
-} // namespace armnn
\ No newline at end of file
+} // namespace armnn