At the company I work for, we have 5 (off the top of my head) different micro services written in Sinatra. Two front end applications built in AngularJS, running off a NodeJS backend (which serves the static content), and one Rails application.<p>For the micro-services, Sinatra does the job very well, there is no need for all of the components that Rails provides; we like the flexibility.<p>Our front end developers have complete ownership of the two front-end apps, and they rolled with NodeJS because it allowed them to take advantage of their JavaScript skills.<p>The Rails app is an internal consumption app. It doesn&#x27;t need to be fancy or have a need to scale. Rails and Bootstrap keep it simple stupid.<p>The meat of our stack is actually on the big data technologies we deal with, RedShift and Hive. We could honestly re-write any of the micro-services in .NET or any other stack for that matter, and still keep our infrastructure mostly the same.