diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3371d86..3adb0d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.4.0] - 2022-03-19
+
+### Switch to truemail-rack 0.4.0
+
 ## [0.3.0] - 2022-01-20
 
 ### Switch to truemail-rack 0.3.1
diff --git a/Dockerfile b/Dockerfile
index 080d07e..f18aba2 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,9 +1,9 @@
-FROM ruby:3.1.0-alpine as Builder
+FROM ruby:3.1.1-alpine as Builder
 ENV APP_HOME="/var/lib/truemail-rack" \
     TMP="/var/lib/truemail-rack/tmp"
 RUN apk add --virtual build-dependencies git && \
     git clone https://github.com/truemail-rb/truemail-rack.git $TMP -q && \
-    cd $TMP && git checkout v0.3.1 -q && \
+    cd $TMP && git checkout v0.4.0 -q && \
     mv app config config.ru .ruby-version Gemfile* $APP_HOME && rm -rf $TMP && \
     apk del build-dependencies
 WORKDIR $APP_HOME
@@ -15,7 +15,7 @@ RUN apk add --virtual build-dependencies make cmake g++ && \
     find /usr/local/bundle/gems/ -regex ".*\.[coh]" -delete && \
     apk del build-dependencies
 
-FROM ruby:3.1.0-alpine
+FROM ruby:3.1.1-alpine
 ENV INFO="Truemail lightweight rack based web API 🚀" \
     APP_USER="truemail" \
     APP_HOME="/var/lib/truemail-rack" \
diff --git a/README.md b/README.md
index 1398b61..bcd3312 100644
--- a/README.md
+++ b/README.md
@@ -39,7 +39,7 @@ version: "3.7"
 
 services:
   truemail:
-    image: truemail/truemail-rack:v0.3.1 # for latest version you can use just truemail/truemail-rack:latest
+    image: truemail/truemail-rack:v0.4.0 # for latest version you can use just truemail/truemail-rack:latest
     ports:
       - 9292:9292
     environment:
@@ -55,6 +55,7 @@ All Truemail solutions: https://truemail-rb.org
 | Name | Type | Description |
 | --- | --- | --- |
 | [truemail](https://github.com/truemail-rb/truemail) | ruby gem | Configurable framework agnostic plain Ruby email validator, main core |
+| [truemail-go](https://github.com/truemail-rb/truemail-go) | go package | Configurable Golang email validator, main core |
 | [truemail server](https://github.com/truemail-rb/truemail-rack) | ruby app | Lightweight rack based web API wrapper for Truemail |
 | [truemail-ruby-client](https://github.com/truemail-rb/truemail-ruby-client) | ruby gem | Truemail web API client library for Ruby |
 | [truemail-crystal-client](https://github.com/truemail-rb/truemail-crystal-client) | crystal shard | Truemail web API client library for Crystal |