language: ruby
sudo: false
rvm:
  - 2.4.2
  - ruby-head
matrix:
  allow_failures:
    - rvm: ruby-head
  fast_finish: true
before_install:
  - gem uninstall -v '>= 2' -i $(rvm gemdir)@global -ax bundler || true
  - gem install bundler -v '< 2'
cache: bundler
notifications:
  email: false