diff --git a/.travis.yml b/.travis.yml
index 1a44d26d..65871e5a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,6 +22,7 @@ matrix:
           group: edge
 
 before_install:
+    - if [ "$TRAVIS_PHP_VERSION" = "hhvm" ]; then echo 'xdebug.enable = on' >> /etc/hhvm/php.ini; fi
     - if [ -n "$GH_TOKEN" ]; then composer config github-oauth.github.com ${GH_TOKEN}; fi;
 
 install: