[engineerDave]

If you have a good framework behind your project, e.g. Rails, Phoenix. You probably don't need it. I'm a primarily a ruby/Rails developer who is slowly switching to Elixir/Phoenix, and I find myself reaching for React when I need to do very complex User Interface components, mostly Rails. Most of my Phoenix apps so far haven't had big UI components. Outside of that Rails' or Phoenix's built in unobtrusive JS, the new hotwire stuff, or Phoenix's live view is more than sufficient IME. If you're doing a JS based single page app then perhaps but it's pretty complicated and there are probably easier options.

[kirso]

Interesting, what made you go from Rails to Elixir? I always thought that Rails community is great and is a good fit for side-projects and micro-SaaS apps. But yeah, I would say in most cases vanilla JS is fine, and will depend on the case and complexity of the app itself!