Recent merge from the AWS branch to develop requires Ruby 2.3+ to support new syntax. If using RVM and passenger, you can follow this guide. It'll also fix capistrano deploy.
Step-by-step guide
- Check installed ruby versions:
rvm list
rvm install 2.4.1
rvm use --default 2.4.1
gem install bundler
gem install passenger
passenger-install-apache2-module
bundle install
sudo service httpd restart