diff --git a/README.md b/README.md
index 31edc6cd..cefd43e9 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 
 Copyright (c) 2016,2017 Ilya Khaprov <<i.khaprov@gmail.com>>.
 
-__Version:__ 4.8.2
+__Version:__ 4.9.0
 
 [![Hex.pm](https://img.shields.io/hexpm/v/prometheus.svg?maxAge=2592000?style=plastic)](https://hex.pm/packages/prometheus)
 [![Hex.pm](https://img.shields.io/hexpm/dt/prometheus.svg?maxAge=2592000)](https://hex.pm/packages/prometheus)
diff --git a/doc/README.md b/doc/README.md
index cae2f0f2..e330d959 100644
--- a/doc/README.md
+++ b/doc/README.md
@@ -4,7 +4,7 @@
 
 Copyright (c) 2016,2017 Ilya Khaprov <<i.khaprov@gmail.com>>.
 
-__Version:__ 4.8.2
+__Version:__ 4.9.0
 
 [![Hex.pm](https://img.shields.io/hexpm/v/prometheus.svg?maxAge=2592000?style=plastic)](https://hex.pm/packages/prometheus)
 [![Hex.pm](https://img.shields.io/hexpm/dt/prometheus.svg?maxAge=2592000)](https://hex.pm/packages/prometheus)
diff --git a/doc/overview.md b/doc/overview.md
index a60a54ca..8af7b2c3 100644
--- a/doc/overview.md
+++ b/doc/overview.md
@@ -1,6 +1,6 @@
 @copyright 2016,2017 Ilya Khaprov <<i.khaprov@gmail.com>>.
 @title Prometheus.io client for Erlang
-@version 4.8.2
+@version 4.9.0
 
 @doc
 [![Hex.pm](https://img.shields.io/hexpm/v/prometheus.svg?maxAge=2592000?style=plastic)](https://hex.pm/packages/prometheus)
diff --git a/mix.exs b/mix.exs
index 341cbd5b..bdc56db9 100644
--- a/mix.exs
+++ b/mix.exs
@@ -3,7 +3,7 @@ defmodule Prometheus.Mixfile do
 
   def project do
     [app: :prometheus,
-     version: "4.8.2",
+     version: "4.9.0",
      description: description(),
      package: package(),
      deps: deps()]
diff --git a/src/prometheus.app.src b/src/prometheus.app.src
index 7ed2a6a5..063c2b15 100644
--- a/src/prometheus.app.src
+++ b/src/prometheus.app.src
@@ -1,6 +1,6 @@
 {application, prometheus,
  [{description, "Prometheus.io client in Erlang"},
-  {vsn, "4.8.2"},
+  {vsn, "4.9.0"},
   {registered, []},
   {mod, { prometheus, []}},
   {applications,