I am writing an application that uses pub sub between various processes quite heavily. I wrote it at first with the local Registry in elixir and it works great. But eventually I needed processes on a different nodes to subscribe to this data, so I had to look for an alternative.

I looked at gproc and syn and I was not too happy with them. gproc’s api is horrible and barely documented and I can’t even get it to work in global mode. It would be an extremely tough sell to my coworkers. Syn has all sorts of collision detection ability and requires all nodes be connected before it can be initialized, or god knows what happens, and all of that is overkill. All of my registries are on one node, and other nodes just pass a message to them once in awhile. Edit: And after reading it more in depth, I’m not sure process groups are what I’m looking for.

So I started writing my own. After I was about half done I realized I was writing elixir’s local Registry myself but worse, and the only real change that mattered was that I could pass in a name: {:global, :name}, into all of my versions of its functions. Registry makes every possible attempt to prevent you from doing that.

At this point I’m seriously considering copying elixir’s registry and just changing some functions to accept a global name tuple, and the only thing stopping me is that I’m wondering what trouble they were trying to prevent me from causing when they wrote this module in this fashion. So if someone could tell me why what I’m considering doing is a bad idea that’d be great.