diff --git a/block-cache/io_engine.h b/block-cache/io_engine.h
index fd902c1..1704251 100644
--- a/block-cache/io_engine.h
+++ b/block-cache/io_engine.h
@@ -8,6 +8,7 @@
 #include <set>
 #include <string>
 #include <libaio.h>
+#include <vector>
 
 //----------------------------------------------------------------