"From JavaScript" also includes another side: When your frontend is in JS, your backend can be a simple REST API. And building a REST API requires much less framework than building a server-side-rendering webapp does, so it's tempting to use Go or Rust or whatever you like.
You’ll need (probably) at least:
-Database connection
-An ORM
-Middleware against attacks / rate limiting
-Caching
-Jobs / workers
-A rendering engine for email and maybe pdf
-Some sort of admin/backend
-Logging
-Validation
I’ve written an API once from scratch. Actually twice. First time in Modena, because it was all the hype, but it was arcane. Then Sinatra, where I ended up creating all of the above. Rails is excellent for APIs.
Rust is nice, but I’m not sure if I’d like it for all of an API. I don’t like go. Crystal seems great, because it’s typed and it’s also super fast.
Agreed. I still think that ruby is great for jamming out an API (far better in terms of development speed than go or rust) but a lot of the great gems that can speed up development assume server side rendering. That plus the fact that go/rust/whatever are probably more "interesting" and faster (at runtime) than ruby is an additional obstacle (for ruby!).