diff --git a/tools/ndns-export-certificate.cpp b/tools/ndns-export-certificate.cpp
index f3d7b8e..d0cb958 100644
--- a/tools/ndns-export-certificate.cpp
+++ b/tools/ndns-export-certificate.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2019, Regents of the University of California.
+ * Copyright (c) 2014-2020, Regents of the University of California.
  *
  * This file is part of NDNS (Named Data Networking Domain Name Service).
  * See AUTHORS.md for complete list of NDNS authors and contributors.
@@ -23,8 +23,8 @@
 #include "util/util.hpp"
 
 #include <boost/program_options.hpp>
-#include <boost/filesystem.hpp>
-#include <string>
+
+#include <iostream>
 
 int
 main(int argc, char* argv[])