diff --git a/.travis.yml b/.travis.yml
index 2cbd780..7c1f188 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,7 +10,7 @@ services:
 
 before_script:
   - composer self-update && composer --version
-  - composer require satooshi/php-coveralls 0.6.* --dev
+  - composer require satooshi/php-coveralls 0.6.* --dev --prefer-dist
   - mysql -e 'CREATE DATABASE yiitest;';
   - psql -U postgres -c 'CREATE DATABASE yiitest;';
   - tests/unit/data/travis/apc-setup.sh