diff --git a/.travis.yml b/.travis.yml
index de38f74..1039dd0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,11 +1,11 @@
 language: ruby
+cache: bundler
 rvm:
-  - 2.2.9
-  - 2.3.8
-  - 2.4.5
-  - 2.5.5
-  - 2.6.2
-
-sudo: false
-# uncomment this line if your project needs to run something other than `rake`:
-# script: bundle exec rspec spec
+  - 1.9
+  - 2.0
+  - 2.1
+  - 2.2
+  - 2.3
+  - 2.4
+  - 2.5
+  - 2.6