diff --git a/rmf_task/src/rmf_task/Log.cpp b/rmf_task/src/rmf_task/Log.cpp
index 2df6457c..bfa11269 100644
--- a/rmf_task/src/rmf_task/Log.cpp
+++ b/rmf_task/src/rmf_task/Log.cpp
@@ -17,6 +17,7 @@
 
 #include <rmf_task/Log.hpp>
 
+#include <optional>
 #include <stdexcept>
 #include <list>