diff --git a/CHANGELOG.md b/CHANGELOG.md
index 47dae51523..fe77d46529 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 **See the full release notes on the official documentation website: https://www.elastic.co/docs/release-notes/elasticsearch/clients/ruby**
 
+# 9.0.1
+
+- The request headers were updated for Elasticsearch v9: `compatible-with=9` [#2660](https://github.com/elastic/elasticsearch-ruby/pull/2660).
+
 # 9.0.0
 
 Ruby 3.2 and up are tested and supported for 9.0. Older versions of Ruby have reached their end of life. We follow Ruby’s own maintenance policy and officially support all currently maintained versions per [Ruby Maintenance Branches](https://www.ruby-lang.org/en/downloads/branches/). The required Ruby version is set to `2.6` to keep compatiblity wit JRuby 9.3. However, we only test the code against currently supported Ruby versions.
diff --git a/elasticsearch-api/lib/elasticsearch/api/version.rb b/elasticsearch-api/lib/elasticsearch/api/version.rb
index 71e0a5c93b..cfe3ba7dc9 100644
--- a/elasticsearch-api/lib/elasticsearch/api/version.rb
+++ b/elasticsearch-api/lib/elasticsearch/api/version.rb
@@ -17,7 +17,7 @@
 
 module Elasticsearch
   module API
-    VERSION = '9.0.0'.freeze
+    VERSION = '9.0.1'.freeze
     ES_SPECIFICATION_COMMIT = '52c473efb1fb5320a5bac12572d0b285882862fb'.freeze
   end
 end
diff --git a/elasticsearch/elasticsearch.gemspec b/elasticsearch/elasticsearch.gemspec
index c9159c6be4..af51fbec94 100644
--- a/elasticsearch/elasticsearch.gemspec
+++ b/elasticsearch/elasticsearch.gemspec
@@ -46,7 +46,7 @@ Gem::Specification.new do |s|
   s.rdoc_options      = ['--charset=UTF-8']
 
   s.required_ruby_version = '>= 2.6' # For compatibility with JRuby 9.3
-  s.add_dependency 'elasticsearch-api', '9.0.0'
+  s.add_dependency 'elasticsearch-api', '9.0.1'
   s.add_dependency 'elastic-transport', '~> 8.3'
 
   s.add_development_dependency 'base64'
diff --git a/elasticsearch/lib/elasticsearch/version.rb b/elasticsearch/lib/elasticsearch/version.rb
index 33758a0941..c745276d84 100644
--- a/elasticsearch/lib/elasticsearch/version.rb
+++ b/elasticsearch/lib/elasticsearch/version.rb
@@ -16,5 +16,5 @@
 # under the License.
 
 module Elasticsearch
-  VERSION = '9.0.0'.freeze
+  VERSION = '9.0.1'.freeze
 end