diff --git a/tools/server/server-http.h b/tools/server/server-http.h
index fede8c8f3..25c7f1062 100644
--- a/tools/server/server-http.h
+++ b/tools/server/server-http.h
@@ -7,6 +7,7 @@
 #include <thread>
 #include <vector>
 #include <cstdint>
+#include <unordered_map>
 
 struct common_params;