diff --git a/Gemfile.lock b/Gemfile.lock
index d5dc5f7..0dd1d36 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -238,7 +238,7 @@
     tzinfo (1.2.7)
       thread_safe (~> 0.1)
     unicode-display_width (1.7.0)
-    zeitwerk (2.3.0)
+    zeitwerk (2.3.1)
 
 PLATFORMS
   ruby
diff --git a/atom.xml b/atom.xml
index 0812812..f8caf14 100644
--- a/atom.xml
+++ b/atom.xml
@@ -4,7 +4,7 @@
  <title>Apache Submarine</title>
  <link href="https://submarine.apache.org//" rel="self"/>
  <link href="https://submarine.apache.org/"/>
- <updated>2020-06-26T13:59:49+00:00</updated>
+ <updated>2020-07-05T10:31:32+00:00</updated>
  <id>https://submarine.apache.org/</id>
  <author>
    <name>The Apache Software Foundation</name>
diff --git a/contribution/contributions.html b/contribution/contributions.html
index 646260c..89b4742 100644
--- a/contribution/contributions.html
+++ b/contribution/contributions.html
@@ -213,6 +213,12 @@
   
     
       
+        
+      
+    
+  
+    
+      
     
   
     
diff --git a/contribution/documentation.html b/contribution/documentation.html
index 364237d..c0a753b 100644
--- a/contribution/documentation.html
+++ b/contribution/documentation.html
@@ -213,6 +213,12 @@
   
     
       
+        
+      
+    
+  
+    
+      
     
   
     
diff --git a/contribution/webapplication.html b/contribution/webapplication.html
index 47b00d5..8dc40a5 100644
--- a/contribution/webapplication.html
+++ b/contribution/webapplication.html
@@ -205,6 +205,12 @@
   
     
       
+        
+      
+    
+  
+    
+      
     
   
     
diff --git a/download.html b/download.html
index 8a657b0..db443b8 100644
--- a/download.html
+++ b/download.html
@@ -131,40 +131,48 @@
 
 <div class="row">
   <div class="col-md-12">
-    <!--
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
+    <!-- 
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
 
-http://www.apache.org/licenses/LICENSE-2.0
+  http://www.apache.org/licenses/LICENSE-2.0
 
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License. 
 -->
 
 <h1>Download Apache Submarine</h1>
 
-<p>The latest release of Apache Submarine is <strong>0.3.0</strong>.</p>
+<p>The latest release of Apache Submarine is <strong>0.4.0</strong>.</p>
 
 <ul>
-<li><p>Apache Submarine 0.3.0 released on Feb 01, 2020 (<a href="./releases/submarine-release-0.3.0.html">release notes</a>) (<a href="https://github.com/apache/submarine/tree/rel/release-0.3.0">git tag</a>)</p>
+<li>Apache Submarine 0.4.0 released on Jul 05, 2020 (<a href="./releases/submarine-release-0.4.0.html">release notes</a>) (<a href="https://github.com/apache/submarine/tree/rel/release-0.4.0">git tag</a>)
 
 <ul>
-<li>Binary package (<a href="https://github.com/apache/submarine#quick-start">Install guide</a>):
-<p><div class="btn btn-md btn-primary" onclick="window.location.href='https://www.apache.org/dyn/closer.cgi/submarine/submarine-0.3.0/submarine-dist-0.3.0-hadoop-2.9.tar.gz'">submarine-dist-0.3.0-hadoop-2.9.tar.gz</div> (550 MB,
-<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-hadoop-2.9.tar.gz.sha512">checksum</a>,
-<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-hadoop-2.9.tar.gz.asc">signature</a>)</p></li>
+<li>Binary package:
+<p>
+<div class="btn btn-md btn-primary" onclick="window.location.href='https://www.apache.org/dyn/closer.cgi/submarine/submarine-0.4.0/submarine-dist-0.4.0-hadoop-2.9.tar.gz'">submarine-dist-0.4.0-hadoop-2.9.tar.gz</div> (642 MB, <a href="https://www.apache.org/dist/submarine/submarine-0.4.0/submarine-dist-0.4.0-hadoop-2.9.tar.gz.sha512">checksum</a>, <a href="https://www.apache.org/dist/submarine/submarine-0.4.0/submarine-dist-0.4.0-hadoop-2.9.tar.gz.asc">signature</a>)
+</p></li>
 <li>Source:
-<p><div class="btn btn-md btn-primary" onclick="window.location.href='https://www.apache.org/dyn/closer.cgi/submarine/submarine-0.3.0/submarine-dist-0.3.0-src.tar.gz'">submarine-dist-0.3.0-src.tar.gz</div> (6 MB,
-<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-src.tar.gz.sha512">checksum</a>,
-<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-src.tar.gz.asc">signature</a>)
-<p></p></li>
+<p>
+<div class="btn btn-md btn-primary" onclick="window.location.href='https://www.apache.org/dyn/closer.cgi/submarine/submarine-0.4.0/submarine-dist-0.4.0-src.tar.gz'">submarine-dist-0.4.0-src.tar.gz</div> (14 MB, <a href="https://www.apache.org/dist/submarine/submarine-0.4.0/submarine-dist-0.4.0-src.tar.gz.sha512">checksum</a>, <a href="https://www.apache.org/dist/submarine/submarine-0.4.0/submarine-dist-0.4.0-src.tar.gz.asc">signature</a>)
+</p></li>
 <li>Docker images:
-<p><em><a href="https://hub.docker.com/layers/apache/submarine/mini-0.3.0/images/sha256-3dd49054bf8a91521f5743c675278d626a5fa568e91651c67867b8ba6ceba340">mini-submarine</a></em> <a href="https://github.com/apache/submarine/blob/rel/release-0.3.0/dev-support/mini-submarine/README.md#mini-submarine">(guide)</a>:</p>
-<code>docker run -it -h submarine-dev --name mini-submarine --net=bridge --privileged -P apache/submarine:mini-0.3.0 /bin/bash</code></li>
+
+<ul>
+<li><a href="https://hub.docker.com/layers/apache/submarine/mini-0.4.0/images/sha256-3dd49054bf8a91521f5743c675278d626a5fa568e91651c67867b8ba6ceba340">mini-submarine</a> <code>docker pull apache/submarine:mini-0.4.0</code></li>
+<li><a href="https://hub.docker.com/layers/apache/submarine/server-0.4.0/images/sha256-9e9775e0ed2ac9d4b108dd747dfb4f4fc27cee0fdd19501e1f53db30d966a3db">submarine server</a> <code>docker pull apache/submarine:server-0.4.0</code></li>
+<li><a href="https://hub.docker.com/layers/apache/submarine/database-0.4.0/images/sha256-5edf4aac2c14e14f78a9955bd84757879e1c05266c1edd5a7d5ef08b6359a400">submarine database</a> <code>docker pull apache/submarine:database-0.4.0</code></li>
+</ul></li>
 </ul></li>
 </ul>
 
@@ -181,6 +189,20 @@
 <h2>Old releases</h2>
 
 <ul>
+<li><p>Apache Submarine 0.3.0 released on Feb 01, 2020 (<a href="./releases/submarine-release-0.3.0.html">release notes</a>) (<a href="https://github.com/apache/submarine/tree/rel/release-0.3.0">git tag</a>)</p>
+
+<ul>
+<li>Binary package with submarine:
+<a style="cursor:pointer" onclick="window.location.href='https://www.apache.org/dyn/closer.cgi/submarine/submarine-0.3.0/submarine-dist-0.3.0-hadoop-2.9.tar.gz'">submarine-dist-0.3.0-hadoop-2.9.tar.gz</a> (550 MB,
+<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-hadoop-2.9.tar.gz.sha512">checksum</a>,
+<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-hadoop-2.9.tar.gz.asc">signature</a>)</li>
+<li>Source:
+<a style="cursor:pointer" onclick="window.location.href='https://www.apache.org/dyn/closer.cgi/submarine/submarine-0.3.0/submarine-dist-0.3.0-src.tar.gz'">submarine-dist-0.3.0-src.tar.gz</a> (6 MB,
+<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-src.tar.gz.sha512">checksum</a>,
+<a href="https://www.apache.org/dist/submarine/submarine-0.3.0/submarine-dist-0.3.0-src.tar.gz.asc">signature</a>)</li>
+<li>Docker images:
+<em><a href="https://hub.docker.com/layers/apache/submarine/mini-0.3.0/images/sha256-3dd49054bf8a91521f5743c675278d626a5fa568e91651c67867b8ba6ceba340">mini-submarine</a></em> <a href="https://github.com/apache/submarine/blob/rel/release-0.3.0/dev-support/mini-submarine/README.md#mini-submarine">(guide)</a></li>
+</ul></li>
 <li><p>Apache Submarine 0.2.0 released on Jul 2, 2019</p>
 
 <ul>
diff --git a/releases/submarine-release-0.4.0.html b/releases/submarine-release-0.4.0.html
new file mode 100644
index 0000000..d32fc49
--- /dev/null
+++ b/releases/submarine-release-0.4.0.html
@@ -0,0 +1,183 @@
+
+
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <title>Apache Submarine Release 0.4.0</title>
+    <meta name="description" content="">
+    <meta name="author" content="The Apache Software Foundation">
+
+    <!-- Enable responsive viewport -->
+    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
+
+    <!-- Le HTML5 shim, for IE6-8 support of HTML elements -->
+    <!--[if lt IE 9]>
+      <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
+    <![endif]-->
+
+    <!-- Le styles -->
+    <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
+    <link href="https://fonts.googleapis.com/icon?family=Material+Icons">
+    <link href="/assets/themes/submarine/bootstrap/css/bootstrap.css" rel="stylesheet">
+    <link href="/assets/themes/submarine/css/style.css?body=1" rel="stylesheet" type="text/css">
+    <link href="/assets/themes/submarine/css/syntax.css" rel="stylesheet"  type="text/css" media="screen" /> 
+    <!-- Le fav and touch icons -->
+    <!-- Update these with your own images
+    <link rel="shortcut icon" href="images/favicon.ico">
+    <link rel="apple-touch-icon" href="images/apple-touch-icon.png">
+    <link rel="apple-touch-icon" sizes="72x72" href="images/apple-touch-icon-72x72.png">
+    <link rel="apple-touch-icon" sizes="114x114" href="images/apple-touch-icon-114x114.png">
+    -->
+    <link rel="apple-touch-icon" sizes="180x180" href="/assets/themes/submarine/img/favicon/apple-touch-icon.png">
+    <link rel="icon" type="image/png" sizes="32x32" href="/assets/themes/submarine/img/favicon/favicon-32x32.png">
+    <link rel="icon" type="image/png" sizes="16x16" href="/assets/themes/submarine/img/favicon/favicon-16x16.png">
+    <link rel="icon" type="image/png" href="/assets/themes/submarine/img/favicon/favicon.ico">
+    <link rel="manifest" href="/assets/themes/submarine/img/favicon/manifest.json">
+    <link rel="mask-icon" href="/assets/themes/submarine/img/favicon/safari-pinned-tab.svg" color="#438bc9">
+    <meta name="theme-color" content="#ffffff">
+
+    <!-- Js -->
+    <script src="https://code.jquery.com/jquery-1.10.2.min.js"></script>
+    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.3.15/angular.min.js"></script>
+    <script src="https://angular-ui.github.io/bootstrap/ui-bootstrap-tpls-2.5.0.js"></script>
+    <script src="/assets/themes/submarine/bootstrap/js/bootstrap.min.js"></script>
+    <script src="/assets/themes/submarine/js/docs.js"></script>
+    <script src="/assets/themes/submarine/js/anchor.min.js"></script>
+    <script src="/assets/themes/submarine/js/moment.min.js"></script>
+    <script src="/assets/themes/submarine/js/helium.controller.js"></script>
+    <script src="/assets/themes/submarine/js/medium.controller.js"></script>
+
+    <!-- atom & rss feed -->
+    <link href="/atom.xml" type="application/atom+xml" rel="alternate" title="Sitewide ATOM Feed">
+    <link href="/rss.xml" type="application/rss+xml" rel="alternate" title="Sitewide RSS Feed">
+  </head>
+
+  <body>
+    
+    <div class="navbar navbar-inverse navbar-fixed-top" role="navigation">
+  <div class="container">
+    <div class="navbar-header">
+      <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
+        <span class="sr-only">Toggle navigation</span>
+        <span class="icon-bar"></span>
+        <span class="icon-bar"></span>
+        <span class="icon-bar"></span>
+      </button>
+      <a class="navbar-brand" href="/">
+        <img src="/assets/themes/submarine/img/submarine_white_logo.png" style="margin-top: -6px;" width="80" alt="I'm submarine">
+        <span style="margin-left: 0px;"> Apache Submarine </span>
+        <!-- <span style="margin-left: 4px; font-size: 16px; font-family: Arial;">0.4.0</span> -->
+      </a>
+    </div>
+
+    <nav class="navbar-collapse collapse" role="navigation">
+      <ul class="nav navbar-nav navbar-right">
+        <!-- Quick Start -->
+        <li class="docs">
+          <a href="#" data-toggle="dropdown" class="dropdown-toggle">Quick Start<b class="caret"></b></a>
+          <ul class="dropdown-menu">
+            <li><a href="https://github.com/apache/submarine/blob/master/docs/userdocs/yarn">Submarine on YARN</a></li>
+            <li><a href="https://github.com/apache/submarine/blob/master/docs/userdocs/k8s">Submarine on K8s</a></li>
+          </ul>
+        </li>
+
+        <!-- Download -->
+        <li><a href="/download.html">Download</a></li>
+
+        <!-- Docs -->
+        <li><a href="https://github.com/apache/submarine/tree/master/docs">Docs</a></li>
+
+        <!-- GitHub -->
+        <li>
+          <a href="https://github.com/apache/submarine">GitHub</a>
+        </li>
+
+        <!-- Community -->
+        <li class="docs">
+          <a href="#" data-toggle="dropdown" class="dropdown-toggle">Community<b class="caret"></b></a>
+          <ul class="dropdown-menu">
+            <li><a href="/community/contributors.html">Contributors</a></li>
+            <li><a href="/community/member.html">Member</a></li>
+          </ul>
+        </li>
+
+        <!-- Apache -->
+        <li class="docs">
+          <a href="#" data-toggle="dropdown" class="dropdown-toggle">Apache<b class="caret"></b></a>
+          <ul class="dropdown-menu">
+            <li><a href="http://www.apache.org/foundation/how-it-works.html">Apache Software Foundation</a></li>
+            <li><a href="http://www.apache.org/licenses/">Apache License</a></li>
+            <li><a href="http://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li>
+            <li><a href="/assets.html">Assets</a></li>
+            <li><a href="http://www.apache.org/foundation/thanks.html">Thanks</a></li>
+          </ul>
+        </li>
+      </ul>
+    </nav>
+  </div>
+</div>
+
+
+
+
+    <div class="content">
+      
+
+<!--<div class="hero-unit Apache Submarine Release 0.4.0">
+  <h1></h1>
+</div>
+-->
+
+<div class="row">
+  <div class="col-md-12">
+    <!--
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<h2>Apache Submarine Release 0.4.0</h2>
+
+<p>The Apache Submarine Community is pleased to announce the availability of the 0.4.0 release.</p>
+
+<p>The community put significant effort into improving Apache Submarine since the last release.
+175 patches for improvements and bug fixes. The highlighted features are as follows:</p>
+
+<ul>
+<li>Submarine Experiments: Refactor the Job to experiment and redefined the experiment spec</li>
+<li>Submarine Helm Charts: Provides one command to install the submarine into the Kubernetes cluster</li>
+<li>PySubmarine: Submarine Python SDK</li>
+</ul>
+
+<p>We encourage to <a href="../../download.html">download</a> the latest release. Feedback through the <a href="../../community/contributors.html#mailing-list">mailing lists</a> is very welcome.</p>
+
+<p><br />
+You can visit <a href="https://issues.apache.org/jira/secure/ReleaseNote.jspa?projectId=12322824&version=12346621">issue tracker</a> for full list of issues that are resolved.</p>
+
+<p><br /></p>
+
+  </div>
+</div>
+
+
+    </div>
+
+    
+
+
+    
+    <footer>
+      <!-- <p>&copy; 2020 The Apache Software Foundation</p>-->
+    </footer>
+  </body>
+</html>
+
diff --git a/rss.xml b/rss.xml
index b00b870..b8206d9 100644
--- a/rss.xml
+++ b/rss.xml
@@ -5,8 +5,8 @@
         <description>Apache Submarine - The Apache Software Foundation</description>
         <link>https://submarine.apache.org/</link>
         <link>https://submarine.apache.org/</link>
-        <lastBuildDate>2020-06-26T13:59:49+00:00</lastBuildDate>
-        <pubDate>2020-06-26T13:59:49+00:00</pubDate>
+        <lastBuildDate>2020-07-05T10:31:32+00:00</lastBuildDate>
+        <pubDate>2020-07-05T10:31:32+00:00</pubDate>
         <ttl>1800</ttl>
 
 
diff --git a/sitemap.txt b/sitemap.txt
index 707329c..e6cac0b 100644
--- a/sitemap.txt
+++ b/sitemap.txt
@@ -14,5 +14,6 @@
 https://submarine.apache.org//sitemap.txt
 https://submarine.apache.org//releases/submarine-release-0.2.0
 https://submarine.apache.org//releases/submarine-release-0.3.0
+https://submarine.apache.org//releases/submarine-release-0.4.0
 https://submarine.apache.org//supported_interpreters
 https://submarine.apache.org//contribution/webapplication