diff --git a/.travis.yml b/.travis.yml
index 5e97e19..0db1b23 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,7 +22,7 @@ before_script:
   - "yarn add mocha@$MOCHA_VERSION"
 
 script:
-  - npm run cover
+  - yarn run cover
 
 after_success:
   - bash <(curl -s https://codecov.io/bash)
diff --git a/appveyor.yml b/appveyor.yml
index 5ad5d89..e852695 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -16,14 +16,14 @@ environment:
 install:
   # Get the wanted version of Node
   - ps: Install-Product node $env:nodejs_version x64
-  # Typical npm stuff.
-  - npm install || (timeout 30 && npm install)
+  # Typical yarn stuff.
+  - yarn install || (timeout 30 && yarn install)
 
 # test scripts
 test_script:
   # Output useful info for debugging.
   - node --version
-  - npm --version
+  - yarn --version
   # run tests
-  - npm run test
+  - yarn run test