diff --git a/.travis.yml b/.travis.yml
index b41dd75..60d4fbb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -25,6 +25,7 @@
   - Xvfb :99 -screen 0 1024x768x24 -extension RANDR &
 
 script:
+  - npm run clean
   - npm run build
   - xvfb-maybe npm test
   - npm run docs