diff --git a/HISTORY.md b/HISTORY.md
index 25d07cb..cf841f2 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,3 +1,8 @@
+## 07.21.2013
+
+* rewrite hash_reader, now it will keep a wait_download cache
+* change hash_writer(crawler) to insert unique hash
+
 ## 07.19.2013
 
 * add simple json searhch api to http
diff --git a/ebin/dhtcrawler.app b/ebin/dhtcrawler.app
index f29e28c..67fc66a 100644
--- a/ebin/dhtcrawler.app
+++ b/ebin/dhtcrawler.app
@@ -1,6 +1,6 @@
 {application,dhtcrawler,
              [{description,"A DHT crawler to index magnet hash to torrent"},
-              {vsn,"75b3d82"},
+              {vsn,"dcf0181"},
               {registered,[dht_crawler_sup]},
               {applications,[kernel,stdlib,crypto,public_key,ssl,inets,bson,
                              mongodb]},
diff --git a/ebin/hash_download_cache.beam b/ebin/hash_download_cache.beam
index a6f10a1..3742e79 100644
Binary files a/ebin/hash_download_cache.beam and b/ebin/hash_download_cache.beam differ