diff --git a/.travis.yml b/.travis.yml
index dfc4b1b4a..aa77f18f5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,6 @@
 language: ruby
 rvm:
+  -2.4.0
   - 2.5.3
   - 2.6.0
   - 2.6.5