diff --git a/passphrase_cache.hh b/passphrase_cache.hh
index 4a82a3c..74cddbc 100644
--- a/passphrase_cache.hh
+++ b/passphrase_cache.hh
@@ -22,6 +22,8 @@ namespace pEp {
             time_point tp;
         };
         using cache = std::list<cache_entry>;
+        using interator = cache::iterator;
+        using const_iterator = cache::const_iterator;
 
         cache _cache;   
         std::mutex _mtx;