diff --git a/.travis.yml b/.travis.yml
index e280e95..a742b12 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,5 +3,6 @@ before_install:
 
 rvm:
   - 2.2.2 # NOTE: 2.2.1 or lower aren't supported by activesupport 5.0, CI isn't needed for such legacy versions.
-  - 2.2.5
-  - 2.3.1
\ No newline at end of file
+  - 2.2.6
+  - 2.3.3
+  - 2.4.0
\ No newline at end of file