diff --git a/include/hexagram/dict.h b/include/hexagram/dict.h
index 3f9b08c..09912f0 100644
--- a/include/hexagram/dict.h
+++ b/include/hexagram/dict.h
@@ -19,10 +19,6 @@ typedef struct _hexagram_dict_bucket {
     hexagram_dict_slot slots[16];
 } hexagram_dict_bucket;
 
-typedef void (hexagram_dict_retainer)(void *);
-
-typedef void (hexagram_dict_releaser)(void *);
-
 typedef struct _hexagram_dict {
     hexagram_dict_bucket *bucket;
 } hexagram_dict;