I tried it out at the start of a new project last year. After 3 weeks, I finally threw in the towel and started from scratch in plain phoenix. By day 2 or 3 I'd surpassed what I'd managed to somehow get working, mostly by trial and error, in Ash.
I am 100% on board with the vision, but the learning curve is absolutely brutal, and at least at the time the documentation was simply not anywhere close to where it needed to be. Something this different needs a truly giant "cookbook" to show, you know, how to use the damn thing. That was lacking and there was nothing to learn from online besides the most basic toy applications. Also, it was, at least at the time, slow as hell. All those damn macros.
Plus - elixir is already niche. Ash is a niche within a niche. I need to be able to hire people who can get up to speed in days, not weeks or months. There's a chicken and egg problem with something this ambitious - no-one uses it because no-one uses it. I hope it breaks out of this dilemma but professionally I can't bet the company that it does.
As I said I really like the idea. Anyone who has maintained an OpenAPI app will jump for joy with documentation and tests moving automatically and in lockstep with the core domain logic. But for me, at the time, it was too early, too risky and too obscure. I do wish it well though - I love these kind of moonshots and I look forward to trying it again as soon as I can.
how did you handle serving more than one version of your OpenAPI endpoint?