Using bundler 1.17.3
Fetching hitimes 1.3.1
Installing hitimes 1.3.1 with native extensions
Gem::InstallError: hitimes requires Ruby version >= 2.2.2.
An error occurred while installing hitimes (1.3.1), and Bundler cannot continue.
Make sure that `gem install hitimes -v '1.3.1' --source 'https://rubygems.org/'`
succeeds before bundling.
In Gemfile:
  celluloid was resolved to 0.17.4, which depends on
    celluloid-essentials was resolved to 0.20.5, which depends on
      timers was resolved to 4.1.2, which depends on
        hitimes