diff --git a/.travis.yml b/.travis.yml
index 8741093..315599c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,7 +4,13 @@ php:
   - 5.3
   - 5.4
   - 5.5
+  - hhvm
 
 script:
   - phpunit --coverage-text
   - phpunit --group unicode --coverage-text
+
+matrix:
+  allow_failures:
+    - php: hhvm
+  fast_finish: true