diff --git a/.ruby-version b/.ruby-version
index 00355e29..59aa62c1 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.3.7
+2.4.5
diff --git a/Gemfile b/Gemfile
index 0704c524..65b26f6b 100755
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
-ruby '2.3.7'
+ruby '2.4.5'
 gem 'rake'
 gem 'rails', '~> 4.2.8'
 gem 'rails_12factor'
diff --git a/docker/build/Dockerfile b/docker/build/Dockerfile
index 0440e52f..6ae5cf0a 100644
--- a/docker/build/Dockerfile
+++ b/docker/build/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.3.7-stretch
+FROM ruby:2.4.5-stretch
 ARG USER
 RUN mkdir /myapp
 COPY script/build/debian/prebuild.sh myapp/script/build/debian/prebuild.sh
diff --git a/docker/debug/Dockerfile b/docker/debug/Dockerfile
index e9c3469c..c9e5c3c6 100644
--- a/docker/debug/Dockerfile
+++ b/docker/debug/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.3.7-stretch
+FROM ruby:2.4.5-stretch
 ARG USER
 RUN mkdir /myapp
 COPY script/build/debian/prebuild.sh myapp/script/build/debian/prebuild.sh