diff --git a/.travis.yml b/.travis.yml
index 4c96096..42a439c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,6 @@
 rvm:
-  - 2.3
   - 2.4
-  - 2.5
+  - 2.6
 before_install: gem install bundler
 language: ruby
 script: script/cibuild