diff --git a/CMakeLists.txt b/CMakeLists.txt
index 12aa920..57efcf4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -142,6 +142,7 @@ foreach(lib screen dom component)
     target_compile_options(${lib} PRIVATE "-Wextra")
     target_compile_options(${lib} PRIVATE "-pedantic")
     target_compile_options(${lib} PRIVATE "-Werror")
+    target_compile_options(${lib} PRIVATE "-Wmissing-declarations")
     target_compile_options(${lib} PRIVATE "-Wno-sign-compare")
   endif()
 
diff --git a/src/ftxui/dom/separator.cpp b/src/ftxui/dom/separator.cpp
index a95701c..0997d6e 100644
--- a/src/ftxui/dom/separator.cpp
+++ b/src/ftxui/dom/separator.cpp
@@ -1,3 +1,4 @@
+#include "ftxui/dom/elements.hpp"
 #include "ftxui/dom/node.hpp"
 
 namespace ftxui {
diff --git a/src/ftxui/dom/text.cpp b/src/ftxui/dom/text.cpp
index 53c3b8b..0a30f7d 100644
--- a/src/ftxui/dom/text.cpp
+++ b/src/ftxui/dom/text.cpp
@@ -1,4 +1,5 @@
 #include <algorithm>
+#include "ftxui/dom/elements.hpp"
 #include "ftxui/dom/node.hpp"
 #include "ftxui/screen/string.hpp"