So you're implying that a simple service that could be implemented with Sinatra should not be considered over engineered because the dev tried to hammer on the problem with Rails?

Background: Just today I read that DHH considered Phoenix pretty cool, but Rails is enough if you don't need the real-time features.

Anyway, of course you can build your services how you like and it's probably a lot fun to use Phoenix :D

- If I have to choose a Ruby tech, I would go for Rails, no Sinatra, no Padrino, nop. Whatever you think is simple now it will change in the future. So start with what you know well and has everything you might need, even if you're not using it now. I've seen many "small" services being rewritten in Rails for this reason and that's painful and a waste of resources.

- Nowadays I have several reasons not to use Rails for new projects (https://blog.jaredfriedman.com/2015/09/15/why-i-wouldnt-use-...). But I actually I have more reasons to use Elixir instead (https://medium.com/@kenmazaika/why-im-betting-on-elixir-7c8f...) (http://blog.carbonfive.com/2016/04/19/elixir-and-phoenix-the...). And yes, it's fun, incredibly robust and scalable. :D