I’m not sure that is the core issue - it probably has more to do with the “I want to do Rails/Sidekiq in Elixir/Phoenix” approach. Lots of people approach Elixir/Phoenix with a “I learn best by doing a interesting project” attitude, not allowing for the fact that their current mindset may not be ideal for working with Elixir/Phoenix. This is a theme in Cameron Price’s Micropatterns: Learning to Reach Quickly for the Right Tool - where he found out that for him personally it was necessary to do lots of little exercises before his mindset shifted sufficiently before it made sense to attempt a larger project.
Now I know nothing about either Sidekiq or Verk but from scanning Verk’s documentation I’m getting the impression that the intention is to insert Verk into your application’s supervision tree - much like Ecto is running in the supervision tree of the application that is running Phoenix - so you are also confronted headfirst with OTP.
This is where another common point of confusion comes into play:
mix new hello_world
creates a library application, while
mix new hello_world --sup
creates what you more conventionally would think of as an “application”. A library application doesn’t implement the application callbacks and as a result can’t be started or stopped. Most library applications will however still autonomously manage their own processes once they are included in the primary application’s supervision tree.
So it seems to me that Verk’s primary intent is to be run in the same primary application that is already running Ecto and the various bits that Phoenix relies on like Cowboy.
I’m used to having app and worker processes separated and scaling them separately. As such, I might have one app server on one box and 3 workers on other boxes.
Now this describes a somewhat different situation. Usually a “box” is running a node and it’s the node that is running your primary application. So each “box” runs it’s own node with applications running in it. Your description sounds like you intend to run Verk on a node that is separate from Phoenix (possibly even Ecto as part of yet another application on yet another node). This can be accomplished with distributed Elixir but interestingly:
Sorry if I came across as discouraging the use of --no-halt. To me it just seemed more advantageous to seize the opportunity to shed a bit more light of what an “application” actually is in the Elixir world rather than sweeping it under the carpet with --no-halt.
