diff --git a/src/User.c b/src/User.c
index bd8a0ab..9461746 100644
--- a/src/User.c
+++ b/src/User.c
@@ -25,6 +25,12 @@
 
 #include <string.h>
 
+struct User
+{
+    Db *db;
+    DbRef *ref;
+};
+
 int
 UserValidate(char *localpart, char *domain)
 {