diff --git a/README.adoc b/README.adoc
index f4ba903..6a99719 100644
--- a/README.adoc
+++ b/README.adoc
@@ -39,7 +39,7 @@ To use the SDK, add the following dependency to your Maven project:
 <dependency>
     <groupId>com.hivemq</groupId>
     <artifactId>hivemq-extension-sdk</artifactId>
-    <version>4.9.20</version>
+    <version>4.9.21</version>
 </dependency>
 ----
 
diff --git a/gradle.properties b/gradle.properties
index c02e4aa..4a5c9bc 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1 +1 @@
-version=4.9.21-SNAPSHOT
+version=4.9.21