diff --git a/.travis.yml b/.travis.yml
index 7b40a54..0a076ce 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,7 +4,9 @@ language: rust
 matrix:
   include:
     - rust: stable
+      - FEATURES="i128"
     - rust: beta
+      - FEATURES="i128"
     - rust: nightly
       env:
       - FEATURES="i128"