diff --git a/.travis.yml b/.travis.yml
index fc571d1..74a80f1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: ruby
 rvm:
-  - 2.5.5
+  - 2.5.8
 services:
   - redis-server
 cache: bundler
diff --git a/Dockerfile b/Dockerfile
index d9b97e6..3f2db5c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,11 +1,11 @@
-FROM ruby:2.5.5
+FROM ruby:2.5.8
 
 RUN apt-get update -qq && apt-get install -y build-essential libpq-dev postgresql-client nodejs poppler-utils advancecomp gifsicle jhead jpegoptim libjpeg-progs optipng pngcrush pngquant
 
 # enable utf8 in irb
 ENV LANG C.UTF-8
 
-RUN gem install bundler --version 2.0.2
+RUN gem install bundler --version 2.1.4
 
 RUN mkdir /app
 WORKDIR /app
@@ -15,4 +15,4 @@ RUN bundle install
 
 ADD . /app
 
-EXPOSE 5000
\ No newline at end of file
+EXPOSE 5000
diff --git a/Gemfile b/Gemfile
index c2bc862..cfc0e64 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
-ruby '2.5.5'
+ruby '2.5.8'
 
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '5.1.7'
diff --git a/Gemfile.lock b/Gemfile.lock
index 97fc447..2070b4c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -445,7 +445,7 @@ DEPENDENCIES
   wikidata-client (~> 0.0.10)
 
 RUBY VERSION
-   ruby 2.5.5p157
+   ruby 2.5.8p224
 
 BUNDLED WITH
-   2.0.2
+   2.1.4
diff --git a/README.md b/README.md
index 757894f..cf4e20b 100644
--- a/README.md
+++ b/README.md
@@ -62,7 +62,7 @@ You just `git pull`ed and now kleineanfragen doesn't start anymore? Try `docker-
 Dependencies
 ------------
 
-* ruby 2.5.5
+* ruby 2.5.8
 * postgres
 * elasticsearch (for search)
 * redis (for sidekiq)