diff --git a/.travis.yml b/.travis.yml
index 17786e6..adfb505 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,7 @@ php:
   - '7.1'
 
 before_script:
-  - composer install --prefer-source --no-interaction --dev
+  - composer install
 
 script:
   - vendor/bin/phpunit