diff --git a/MoltenVK/MoltenVK/GPUObjects/MVKPipeline.mm b/MoltenVK/MoltenVK/GPUObjects/MVKPipeline.mm
index 213eff92d..7a0942930 100644
--- a/MoltenVK/MoltenVK/GPUObjects/MVKPipeline.mm
+++ b/MoltenVK/MoltenVK/GPUObjects/MVKPipeline.mm
@@ -28,6 +28,7 @@
 #endif
 #include "mvk_datatypes.hpp"
 #include <sys/stat.h>
+#include <sstream>
 
 #ifndef MVK_USE_CEREAL
 #define MVK_USE_CEREAL (1)