diff --git a/Gemfile b/Gemfile
index 77ac5a7e..5877787b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,7 @@
 
 source 'https://rubygems.org'
 
-# ruby '~> 2.5.0'
+ruby ENV['TRAVIS_RUBY_VERSION'] || '2.6.6'
 
 # rails-assets requires >= 1.8.4
 if Gem::Version.new(Bundler::VERSION) < Gem::Version.new('1.8.4')
diff --git a/Gemfile.lock b/Gemfile.lock
index 241cbb00..929552b6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -784,5 +784,8 @@ DEPENDENCIES
   webmock
   whenever
 
+RUBY VERSION
+   ruby 2.6.6p146
+
 BUNDLED WITH
    1.17.3