Hi there,

I’m currently investigating Elixir and Phoenix as an alternative to Ruby/Rails for a new project I’m working on.

It’s mainly an API backend and a mobile frontend, with websocket connections between the two, but most data is going through the JSON API.

However, learning more and more Elixir and OTP, I realised we could use Tasks and GenServers for “background jobs” instead of a full fledged job queue as you’d normally do with Rails. Background jobs in our case being things like:

• push notifications send to the mobile clients
• emails
• after-save calculations for our algorithms
• image processing
• search indexing

Now to the real question(s): say we’d use GenServers (potentially together with ETS/Mnesia) to do those things. If we deploy using erlang/elixir releases, the state in the GenServers should persists as far as I understand it, so we shouldn’t lose any unprocessed jobs. Correct?

However, if we deploy using throwaway docker containers, those unprocessed jobs would be gone after deploys.

Long story short, how would you guys handle such a thing? The aforementioned jobs are not super critical (a missed push notification is not the end of the world), but we’d certainly prefer a stable solution. Docker would also be nice from a DevOps perspective, that’s why I’m asking.

We could of course use an external queue with redis/rabbit, but that doesn’t feel like the erlang way, does it?

Hope that’s somewhat clear - thanks in advance!