diff --git a/lib_vector_search/src/grouped_finder.cpp b/lib_vector_search/src/grouped_finder.cpp
index 412ebae..bb8ee88 100644
--- a/lib_vector_search/src/grouped_finder.cpp
+++ b/lib_vector_search/src/grouped_finder.cpp
@@ -14,8 +14,8 @@ GroupedFinder::GroupedFinder(const WordList &word_list) {
   }
 }
 
-std::forward_list<const std::string *>
-GroupedFinder::find_prefix(std::string_view search_prefix) const {
+forward_list<const string *>
+GroupedFinder::find_prefix(string_view search_prefix) const {
   const auto group = groups_.find(search_prefix.front());
   if (group == groups_.cend()) {
     return {};