$ bundle install --path vendor/bundle
$ bundle exec rspec spec/hello_spec.rb
$ export SLACK_API_TOKEN="xoxp-XXXXXXXXXXXXXXXXXXXXXXXXXXXX" # API TOKEN of Slack
$ export SLACK_CHANNEL="#backlog-slack"
$ export SLACK_BOT_USERNAME="Backlog"
$ bundle exec rackup -o 0.0.0.0 -p 8080
$ heroku create backlog-to-slack-api
$ heroku config:set BACKLOG_HOST=xxx.backlog.jp
$ heroku config:set SLACK_API_TOKEN=xoxp-XXXXXXXXXXXXXXXXXXXXXXXXXXXX" # API TOKEN of Slack
$ heroku config:set SLACK_CHANNEL=#backlog-slack
$ heroku config:set SLACK_BOT_USERNAME=Backlog
$ git push heroku master