- https://github.com/doubleunion/arooo/blob/943dc2d6efeed675aba25d6db7be2776d46926f1/lib/google_auth.rb
- https://github.com/gorails-screencasts/sending-webhooks-with-exponential-backoff/commit/60ca8421edee1dd61e610b8fdac76b604b81d49f
- https://github.com/librariesio/libraries.io/blob/master/app/models/web_hook.rb