diff --git a/.travis.yml b/.travis.yml
index 503e63f00..3d0fbc918 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,7 @@ os:
   - osx
 install:
   - ./build/install.sh
-  - if [ "$(uname -s)" != "Darwin" ]; then sudo apt-get update && sudo apt-get install -y zsh; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get update && sudo apt-get install -y zsh; fi
 script:
   - ./script/test
 notifications: