diff --git a/exp/main.cpp b/exp/main.cpp
index 3c4a1b207..27707decb 100644
--- a/exp/main.cpp
+++ b/exp/main.cpp
@@ -20,6 +20,7 @@
  * Ethereum client.
  */
 #include <functional>
+#include <libethereum/AccountDiff.h>
 #include <libdevcore/Log.h>
 #include <libdevcore/Common.h>
 #include <libdevcore/CommonData.h>