[teilo]

My company is an example of this, and in a way that is quite different from that laid out in the article. We actually began with a Python implementation for our integration / API server. But this was well before asyncio and eventlet and kestral. It didn't scale well, and we quickly outgrew it.

We implemented its replacement in Elixir, a solution we are still running. It is written by a developer we still have, is well organized, follows proper functional paradigms, and fully leverages OTP/Genserver. It is resilient, and so far as the one two developers we have working in it at present, easy to maintain. We love it.

But we also are switching back to Python. The reason is simple: We only have two Elixir developers (really only 1.5), and we have far more work than they can complete. And when something breaks (usually because something changed in the various systems being integrated), we have one guy who can fix it, and get our production queues flowing again.

We have looked for more Elixir developers. They are rare beasts. But we have a lot of Python developers. And now that we have asyncio/eventlet/etc., the landscape has drastically changed. In Python, the various teams can create their own worker modules, and do so more efficiently because they know their own workloads far better.

Language diversity IS a problem when it impedes development and puts production at risk.

[bcbrown]

> We have looked for more Elixir developers. They are rare beasts. But we have a lot of Python developers.

Was there any consideration of training up the Python developers on Elixir?

[teilo]

That's the 0.5 Elixir developer. Let's face it: It's easy to become a poor Elixir developer, but those capable of becoming a good Elixir developer such that it's worth the cost of effort to train them, are uncommon.

As the CIO, where the buck stops, I learned Elixir well enough to write my own Genserver-like implementation from scratch, and thoroughly enjoyed it. I wanted to be able to understand the code base. But I am still a far better Python developer than I will ever be an Elixir developer. It's all a question of time utilization.

Due to the modular nature of our integration, it's relatively easy to move from one platform to the other, one module-at-a-time. And in the end, the cost of getting a new Python-based platform up-and-running far outweighed the cost of trying to retrain Python devs.