diff --git a/dlib/serialize.h b/dlib/serialize.h
index 17004ef027..ed8dbd8033 100644
--- a/dlib/serialize.h
+++ b/dlib/serialize.h
@@ -626,6 +626,7 @@ namespace dlib
     USE_DEFAULT_INT_SERIALIZATION_FOR(unsigned long)
     USE_DEFAULT_INT_SERIALIZATION_FOR(uint64)
     USE_DEFAULT_INT_SERIALIZATION_FOR(int64)
+    USE_DEFAULT_INT_SERIALIZATION_FOR(char32_t)
 
     USE_DEFAULT_BYTE_SERIALIZATION_FOR(char)
     USE_DEFAULT_BYTE_SERIALIZATION_FOR(signed char)
diff --git a/dlib/unicode/unicode.h b/dlib/unicode/unicode.h
index c71e052682..ce199b2548 100644
--- a/dlib/unicode/unicode.h
+++ b/dlib/unicode/unicode.h
@@ -16,7 +16,7 @@ namespace dlib
 
 // ----------------------------------------------------------------------------------------
 
-    using unichar = uint32;
+    using unichar = char32_t;
     using ustring = std::basic_string<unichar>;
 
 // ----------------------------------------------------------------------------------------