diff --git a/include/tree_sitter/runtime.h b/include/tree_sitter/runtime.h
index 67141fb3..1143ad0e 100644
--- a/include/tree_sitter/runtime.h
+++ b/include/tree_sitter/runtime.h
@@ -79,6 +79,7 @@ void ts_document_invalidate(TSDocument *);
 TSNode ts_document_root_node(const TSDocument *);
 size_t ts_document_parse_count(const TSDocument *);
 
+size_t ts_language_symbol_count(const TSLanguage *);
 const char *ts_language_symbol_name(TSLanguage *, TSSymbol);
 
 #define ts_builtin_sym_error 0