diff --git a/scripts/gen_i18n.py b/scripts/gen_i18n.py
index 1d8d3e48..89a0ba8f 100755
--- a/scripts/gen_i18n.py
+++ b/scripts/gen_i18n.py
@@ -604,6 +604,7 @@ def generate_strings_cpp(
     """Generate I18nStrings.cpp."""
     lines: List[str] = [
         '#include "I18nStrings.h"',
+        "#include <cstddef>",
         "",
         "// THIS FILE IS AUTO-GENERATED BY gen_i18n.py. DO NOT EDIT.",
         "",