The Ruby on Rails tax. It isn’t impossible to make snappy apps with it, but it must be uneconomical in terms of dev costs because no one does.
So is Shopify and Stripe. They can scale.
These days, if I want something that has some of the ergonomics of Rails in a platform I know can scale better than Ruby, I reach for Elixir/Phoenix.
In any case, it's a closed source, underfeatured, Microsoft owned platform for Open Source software, so what are we doing there anyway?
I am personally excited about radicle — a local-first, distributed forge.
Yeah, from my experience administering a pretty small self-hosted instance, I think it's got to be this. Every single admin action you try to take on the backend is SLOWWWWW. Restarting the services takes a few minutes. Just to bring up an admin console on the server in a CLI takes well over a minute, which indicates a tremendous amount of overhead purely on the ruby side.
There's just something fundamentally slow about how it's all put together. I wouldn't blame the language or tech stack, exactly - but perhaps Ruby on Rails is not a great fit, anymore, for a fully featured forge of this scale?
So while Go by default will always be faster then Ruby Rails, there are plenty of examples of decently fast Ruby Rails Apps. Having 10 years saying they will improve performance and not getting any of it suggest problems with Gitlab itself more than RoR.
Basecamp is slow as hell, Shopify depends on some insanely specific tuning, and I don't use Hey but it's the same team as Basecamp IIRC.