diff --git a/librepomgr/webapi/session.cpp b/librepomgr/webapi/session.cpp
index 2b3c711..1a08634 100644
--- a/librepomgr/webapi/session.cpp
+++ b/librepomgr/webapi/session.cpp
@@ -157,7 +157,9 @@ void Session::received(boost::system::error_code ec, size_t bytesTransferred)
     }
     cerr << flush;
 #endif
-    respond(Render::makeNotFound(request, "route \"" % request.method_string().to_string() % ' ' % request.target().to_string() + '\"'));
+    const auto methodString = request.method_string();
+    const auto targetString = request.target();
+    respond(Render::makeNotFound(request, argsToString("route \"", std::string_view(methodString.data(), methodString.size()), ' ', std::string_view(targetString.data(), targetString.size()), '\"')));
 }
 
 void Session::respond(std::shared_ptr<Response> &&response)