Fix travis

Author: winterbe

.travis.yml

@@ -2,13 +2,16 @@ language: node_js
 branches:
   only:
     - master
+before_install:
+  - curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.9.2
+  - export PATH=$HOME/.yarn/bin:$PATH
 cache:
   yarn: true
   directories:
     - node_modules
 notifications:
   email: false
 node_js:
-  - '8.3'
+  - '8.11'
 script:
   - yarn travis

package.json

@@ -36,7 +36,7 @@
     "LICENSE"
   ],
   "engines": {
-    "node": ">=6.0.0"
+    "node": ">=8.11"
   },
   "devDependencies": {
     "@types/jest": "^23.3.1",