diff --git a/.travis.yml b/.travis.yml
index 044c50a..7d91922 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,8 @@ matrix:
     - os: linux
     - os: osx
       osx_image: xcode9.3
+      before_install:
+        - rustup install nightly
 
 script:
   - cargo build --release