diff --git a/src/dwarfs/fragment_order_parser.cpp b/src/dwarfs/fragment_order_parser.cpp
index a35fcda0..f10d2c4d 100644
--- a/src/dwarfs/fragment_order_parser.cpp
+++ b/src/dwarfs/fragment_order_parser.cpp
@@ -76,6 +76,8 @@ void parse_order_option(std::string_view ordname, std::string_view opt,
 } // namespace
 
 std::string fragment_order_parser::choices() {
+  // TODO: C++23
+  // auto tools = std::views::keys(order_choices) | std::views::join_with(", ");
   using namespace folly::gen;
   return from(order_choices) | get<0>() | unsplit<std::string>(", ");
 }
diff --git a/src/universal.cpp b/src/universal.cpp
index 535a1174..462ce4a3 100644
--- a/src/universal.cpp
+++ b/src/universal.cpp
@@ -108,6 +108,8 @@ int SYS_MAIN(int argc, sys_char** argv) {
 
   using namespace folly::gen;
 
+  // TODO: C++23
+  // auto tools = std::views::keys(functions) | std::views::join_with(", ");
   auto tools = from(functions) | get<0>() | unsplit(", ");
 
   // clang-format off