I&#x27;ve been using ClojureScript in production for about a year now. The runtime is very fast, and in some cases it actually outperforms native Js. For example, both Om and Reagent are actually faster than React.js itself (<a href="http:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=VSdnJDO-xdg&amp;t=9m36s" rel="nofollow">http:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=VSdnJDO-xdg&amp;t=9m36s</a>).<p>Debugging story is very good. You pretty much never have to see the generated JavaScript. ClojureScript uses source maps, so any errors in the compiled Js will map back to the original ClojureScript source that caused them. Chrome dev tools even do syntax highlighting for ClojureScript now.<p>Having a live dev environment with Figwheel and a REPL goes a long way here as well. You can inspect a lot of things at runtime very easily.<p>Using immutable data structures by default avoids a lot of the debugging pain as well. You practically never have to trace through a bunch of function calls to find the problem. In most cases the problem is exactly on the line where the error occurred.