--- a/source/MaterialXGenShader/ShaderNode.h
+++ b/source/MaterialXGenShader/ShaderNode.h
@@ -8,7 +8,7 @@
 
 /// @file
 /// Classes for nodes created during shader generation
-
+#include <cstdint>
 #include <MaterialXGenShader/Export.h>
 
 #include <MaterialXGenShader/ShaderNodeImpl.h>
--- a/source/MaterialXGenShader/TypeDesc.h
+++ b/source/MaterialXGenShader/TypeDesc.h
@@ -8,7 +8,7 @@
 
 /// @file
 /// Type descriptor for a MaterialX data type.
-
+#include <cstdint>
 #include <MaterialXGenShader/Export.h>
 #include <MaterialXCore/Value.h>
 #include <MaterialXCore/Document.h>
--- a/source/MaterialXRender/Mesh.h
+++ b/source/MaterialXRender/Mesh.h
@@ -8,7 +8,7 @@
 
 /// @file
 /// Mesh interfaces
-
+#include <cstdint>
 #include <MaterialXCore/Types.h>
 #include <MaterialXRender/Export.h>
 
--- a/source/MaterialXCore/Types.h
+++ b/source/MaterialXCore/Types.h
@@ -15,6 +15,7 @@
 
 #include <array>
 #include <cmath>
+#include <cstdint>
 
 MATERIALX_NAMESPACE_BEGIN