diff --git a/src/wire/json/write.cpp b/src/wire/json/write.cpp
index bef2164..6729147 100644
--- a/src/wire/json/write.cpp
+++ b/src/wire/json/write.cpp
@@ -27,6 +27,7 @@
 
 #include "write.h"
 
+#include <ostream>
 #include <stdexcept>
 
 #include "hex.h" // monero/contrib/epee/include