diff --git a/.travis.yml b/.travis.yml
index c0780cf..62c7a74 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,7 @@ node_js:
   - 8
 
 before_install:
-  - npm install codecov.io coveralls
+  - yarn add codecov.io coveralls -D
 
 script:
   - yarn build