diff --git a/History.md b/History.md
index ea13506c..463d09bf 100644
--- a/History.md
+++ b/History.md
@@ -1,4 +1,14 @@
 
+2.1.1 / 2024-07-10
+==================
+
+### Bug Fixes
+
+* discard acknowledgements upon disconnection ([54645ec](https://github.com/socketio/socket.io-client-java/commit/54645ece2cd132f3e305b80904e1fc38bd41c4f9))
+* make sendBuffer thread safe ([#769](https://github.com/socketio/socket.io-client-java/issues/769)) ([b00ae8e](https://github.com/socketio/socket.io-client-java/commit/b00ae8eec1ef0aa5094fca7fad918a437603eb12))
+
+
+
 1.0.2 / 2022-07-11
 ==================
 
diff --git a/pom.xml b/pom.xml
index 9a36604e..59c4fc32 100644
--- a/pom.xml
+++ b/pom.xml
@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>io.socket</groupId>
   <artifactId>socket.io-client</artifactId>
-  <version>2.1.1-SNAPSHOT</version>
+  <version>2.1.1</version>
   <packaging>jar</packaging>
   <name>socket.io-client</name>
   <description>Socket.IO Client Library for Java</description>
@@ -30,7 +30,7 @@
     <url>https://github.com/socketio/socket.io-client-java</url>
     <connection>scm:git:https://github.com/socketio/socket.io-client-java.git</connection>
     <developerConnection>scm:git:https://github.com/socketio/socket.io-client-java.git</developerConnection>
-    <tag>HEAD</tag>
+    <tag>socket.io-client-2.1.1</tag>
   </scm>
 
   <developers>
@@ -184,7 +184,7 @@
       <plugin>
         <groupId>org.sonatype.plugins</groupId>
         <artifactId>nexus-staging-maven-plugin</artifactId>
-        <version>1.6.7</version>
+        <version>1.6.13</version>
         <extensions>true</extensions>
         <configuration>
           <serverId>ossrh</serverId>
diff --git a/src/site/markdown/changelog.md b/src/site/markdown/changelog.md
index 729acdd2..1939253f 100644
--- a/src/site/markdown/changelog.md
+++ b/src/site/markdown/changelog.md
@@ -1,3 +1,26 @@
+# History
+
+| Version                                                                                                      | Release date  |
+|--------------------------------------------------------------------------------------------------------------|---------------|
+| [2.1.1](#211-2024-07-10)                                                                                     | July 2024     |
+| [1.0.2](#102-2022-07-11) (from the [1.x](https://github.com/socketio/socket.io-client-java/tree/1.x) branch) | July 2022     |
+| [2.1.0](#210-2022-07-10)                                                                                     | July 2022     |
+| [2.0.1](#201-2021-04-27)                                                                                     | April 2021    |
+| [2.0.0](#200-2020-12-14)                                                                                     | December 2020 |
+| [1.0.1](#101-2020-12-10)                                                                                     | December 2020 |
+
+
+# Release notes
+
+## [2.1.1](https://github.com/socketio/socket.io-client-java/compare/socket.io-client-2.1.0...socket.io-client-2.1.1) (2024-07-10)
+
+
+### Bug Fixes
+
+* discard acknowledgements upon disconnection ([54645ec](https://github.com/socketio/socket.io-client-java/commit/54645ece2cd132f3e305b80904e1fc38bd41c4f9))
+* make sendBuffer thread safe ([#769](https://github.com/socketio/socket.io-client-java/issues/769)) ([b00ae8e](https://github.com/socketio/socket.io-client-java/commit/b00ae8eec1ef0aa5094fca7fad918a437603eb12))
+
+
 
 ## [1.0.2](https://github.com/socketio/socket.io-client-java/compare/socket.io-client-1.0.1...socket.io-client-1.0.2) (2022-07-11)
 
diff --git a/src/site/markdown/installation.md b/src/site/markdown/installation.md
index 99318f65..de61a1e7 100644
--- a/src/site/markdown/installation.md
+++ b/src/site/markdown/installation.md
@@ -17,7 +17,7 @@ Add the following dependency to your `pom.xml`.
   <dependency>
     <groupId>io.socket</groupId>
     <artifactId>socket.io-client</artifactId>
-    <version>2.1.0</version>
+    <version>2.1.1</version>
   </dependency>
 </dependencies>
 ```
@@ -26,7 +26,7 @@ Add the following dependency to your `pom.xml`.
 Add it as a gradle dependency for Android Studio, in `build.gradle`:
 
 ```groovy
-implementation ('io.socket:socket.io-client:2.1.0') {
+implementation ('io.socket:socket.io-client:2.1.1') {
   // excluding org.json which is provided by Android
   exclude group: 'org.json', module: 'json'
 }
@@ -36,6 +36,7 @@ implementation ('io.socket:socket.io-client:2.1.0') {
 
 | `socket.io-client`                                                                                                          | `engine.io-client`                                                                                                          | `okhttp`                                                                                        |
 |-----------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------|
+| `2.1.1` ([diff](https://github.com/socketio/socket.io-client-java/compare/socket.io-client-2.1.0...socket.io-client-2.1.1)) | `2.1.0`                                                                                                                     | `3.12.12`                                                                                       |
 | `2.1.0` ([diff](https://github.com/socketio/socket.io-client-java/compare/socket.io-client-2.0.1...socket.io-client-2.1.0)) | `2.1.0` ([diff](https://github.com/socketio/engine.io-client-java/compare/engine.io-client-2.0.0...engine.io-client-2.1.0)) | `3.12.12`                                                                                       |
 | `2.0.1` ([diff](https://github.com/socketio/socket.io-client-java/compare/socket.io-client-2.0.0...socket.io-client-2.0.1)) | `2.0.0`                                                                                                                     | `3.12.12`                                                                                       |
 | `2.0.0` ([diff](https://github.com/socketio/socket.io-client-java/compare/socket.io-client-1.0.1...socket.io-client-2.0.0)) | `2.0.0` ([diff](https://github.com/socketio/engine.io-client-java/compare/engine.io-client-1.0.1...engine.io-client-2.0.0)) | `3.12.12`                                                                                       |