diff --git a/CHANGELOG.md b/CHANGELOG.md
index 37795314..b958565a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 # Changelog
 
+### 0.4.0
+
+FEATURES:
+* [50](https://github.com/nginxinc/nginx-prometheus-exporter/pull/50): Add zone sync metrics support.
+* [37](https://github.com/nginxinc/nginx-prometheus-exporter/pull/37): Implement a way to retry connection to NGINX if it is unreachable. Add -nginx.retries for setting the number of retries and -nginx.retry-interval for setting the interval between retries, both as cli-arguments.
+
+UPGRADE:
+* Use the 0.4.0 image from our DockerHub: `nginx/nginx-prometheus-exporter:0.4.0`
+* Download the latest binaries from [GitHub releases page](https://github.com/nginxinc/nginx-prometheus-exporter/releases/tag/v0.4.0).
+
+COMPATIBILITY:
+* NGINX 0.1.18 or newer.
+* NGINX Plus R18 or newer.
+
 ### 0.3.0
 
 FEATURES:
diff --git a/Makefile b/Makefile
index 8bf14ffd..f38d14ea 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-VERSION = 0.3.0
+VERSION = 0.4.0
 PREFIX = nginx/nginx-prometheus-exporter
 TAG = $(VERSION)
 GIT_COMMIT = $(shell git rev-parse --short HEAD)
diff --git a/README.md b/README.md
index 823fa346..1f7c503a 100644
--- a/README.md
+++ b/README.md
@@ -30,13 +30,13 @@ To start the exporter we use the [docker run](https://docs.docker.com/engine/ref
 
 * To export NGINX metrics, run:
     ```
-    $ docker run -p 9113:9113 nginx/nginx-prometheus-exporter:0.3.0 -nginx.scrape-uri http://<nginx>:8080/stub_status
+    $ docker run -p 9113:9113 nginx/nginx-prometheus-exporter:0.4.0 -nginx.scrape-uri http://<nginx>:8080/stub_status
     ```
     where `<nginx>` is the IP address/DNS name, through which NGINX is available.
 
 * To export NGINX Plus metrics, run:
     ```
-    $ docker run -p 9113:9113 nginx/nginx-prometheus-exporter:0.3.0 -nginx.plus -nginx.scrape-uri http://<nginx-plus>:8080/api
+    $ docker run -p 9113:9113 nginx/nginx-prometheus-exporter:0.4.0 -nginx.plus -nginx.scrape-uri http://<nginx-plus>:8080/api
     ```
     where `<nginx-plus>` is the IP address/DNS name, through which NGINX Plus is available.