diff --git a/include/cxx/cstddef b/include/cxx/cstddef
index 74811d830b1..5c2ca53ed1c 100644
--- a/include/cxx/cstddef
+++ b/include/cxx/cstddef
@@ -76,6 +76,9 @@ namespace std
 
   using ::socklen_t;
   using ::sa_family_t;
+#if __cplusplus >= 201103L
+  using nullptr_t = decltype(nullptr);
+#endif
 }
 
 #endif // __INCLUDE_CXX_CSTDDEF