1 files changed, 3 insertions, 0 deletions
diff --git a/libnitrokey/device.h b/libnitrokey/device.h
index eab3888..4b1c239 100644
--- a/libnitrokey/device.h
+++ b/libnitrokey/device.h
@@ -26,6 +26,7 @@
 #include <cstdint>
 #include <memory>
 #include <string>
+#include <ostream>
 #include <vector>
 #include "misc.h"
 
@@ -52,6 +53,8 @@ enum class DeviceModel{
     STORAGE
 };
 
+std::ostream& operator<<(std::ostream& stream, DeviceModel model);
+
 /**
  * The USB vendor ID for Nitrokey devices.
  */