diff --git a/.travis.yml b/.travis.yml
index 52d497fe..c7155869 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,7 +2,9 @@ language: php
 
 php:
   - "5.4"
+    dist: trusty
   - "5.5"
+    dist: trusty
   - "5.6"
   - "7.0"
   - "7.1"