diff --git a/examples/server/server.cpp b/examples/server/server.cpp
index 865be4d8d..5f08c4ecc 100644
--- a/examples/server/server.cpp
+++ b/examples/server/server.cpp
@@ -26,7 +26,6 @@
 #include <deque>
 #include <memory>
 #include <mutex>
-#include <optional>
 #include <signal.h>
 #include <thread>
 #include <unordered_map>