At UltimateFanLive we use docker on Elastic Beanstalk to speed up the scaling process. Our load goes from 0 to 60 in minutes, as we are connected with live sports data. Packages like numpy and lxml take way too long to install with yum and pip alone. So we pre-build images with the dependencies but we are still using the rest of the goodies on Elastic Beanstalk. Deploy times have plummeted and we keep t2 cpu credits.