[edpass]

Jason's coworker here.

The Erlang benefits you have mentioned above also fully apply to regular web requests and applications. One of Ruby biggest flaws (and consequently Rails') is poor support for concurrency. And Phoenix performs well on all aspects Jason mentioned because running tests, serving data, etc is all done concurrently.

I was also skeptical at first. I've heard talks and benchmarks reporting Phoenix is from 10x to 20x faster than Rails (like this one: https://gist.github.com/omnibs/e5e72b31e6bd25caf39a). After porting our authentication service to Phoenix (our first), we saw similar gains with less CPU and memory usage (as well as better response time averages and 99 percentiles). Our deployment infrastructure for this service is now one fourth of what it was originally.

Other than that, Rails definitely has a huge ecosystem and that should be taken into account by those planning to move to Phoenix. Honestly, it has not impacted us in any significant way but YMMV.