cjshort
I would say in an API-only context, we're seeing a lot of benefits in using RoR for the back-end and pairing it with Tanstack for the front-end.
Realistically, when/if it matters, we'll just port to a quicker language, which is now effortless.
But when you're in build mode, Rails is wonderfully ergonomic (for humans + AI).
Modern Rails is plenty quick (Ruby + Falcon is 2X faster than Python Async) and is incredibly ergonomic for LLMs as a codebase.
The tooling is also incredibly strong, with 200k~ Ruby gems in the ecosystem.
But ultimately, none of this matters. You can use any framework/language now and the LLMs can be productive on them all. Tools missing? Astra one shots it.
If you get to the scale where milliseconds result in $MM bills, then you port with another prompt, or just point more tokens at the bottleneck.