diff --git a/CHANGES.txt b/CHANGES.txt
index 046d103fb5e..78a6dadffc5 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,3 +1,8 @@
+5.5.0.21 - 2018-08-04
+* Fix cassandra discovery for k8s
+* Delete nested documents when truncating a cassandra table
+* Fix concurrent partition read-before-indexing
+
 5.5.0.20 - 2018-07-16
 * #211 Improve ip replacement management
 * Fix race condition when computing the routing table
diff --git a/buildSrc/version.properties b/buildSrc/version.properties
index d04bb003efd..55c07016652 100644
--- a/buildSrc/version.properties
+++ b/buildSrc/version.properties
@@ -1,6 +1,6 @@
 elasticsearch     = 5.5.0
 lucene            = 6.6.0
-elassandra        = 20
+elassandra        = 21
 cassandra         = 3.11.2
 
 # optional dependencies
diff --git a/docs/elassandra/source/conf.py b/docs/elassandra/source/conf.py
index 6c4a94458ef..2cb297df55e 100644
--- a/docs/elassandra/source/conf.py
+++ b/docs/elassandra/source/conf.py
@@ -67,7 +67,7 @@
 # The short X.Y version.
 version = u'5.5.0'
 # The full version, including alpha/beta/rc tags.
-release = u'5.5.0.20'
+release = u'5.5.0.21'
 
 tgz_url = "https://github.com/strapdata/elassandra/releases/download/v{0}/elassandra-{0}.tar.gz".format(release)
 deb_url = "https://github.com/strapdata/elassandra/releases/download/v{0}/elassandra-{0}.deb".format(release)