Client-side (javascript) VS Ruby || NodeJS

This is probably a frequent question however haven’t seen any good explanation.

Which one is more:

safe =>
stable =>
fast =>

Please limit the answers to (client-side vs ruby vs nodejs) and if possible explane why.
Thank you so much for your sharings

Hi @Contente

As I understand, the question related to Ruby on Rails framework.

We are happy to help you with dhtmlx Scheduler and other dhtmlx components on this forum, but infortunately don’t have deep knowledge in Ruby on Rails. I advise you to look for a solution on the Ruby forums.

Hi Polina, sorry my mistake. The question is more related to Javascript client side VS Nodejs
Nodejs handles single thread request, while if the requests are done via browser (client-side) is likely gonna be a multi thread request.
So the question is, which one is best for Scheduler.