Clojurescript has to be compiled by the google closure compiler on the server side. The closure compiler doesn't work out of the box with other libraries, you need some kind of bridge.
Lispyscript has the very nice advantage of being able to run directly in the browser. Since it's translated directly to javascript, I expect it won't have problems using other javascript libraries.
Some inaccuracies here. ClojureScript does not have to be compiled by Google Closure. That pass is an optional one for production builds. There is no "bridging" when using the Closure Compiler with non-Closure compatible code. The issue is that in production mode the Closure Compiler will make aggressive assumptions about what it can rename. So it's not about bridging it's about preventing renaming - again this is only relevant for advanced production builds.
That said for non-Web applications or applications where advanced compilation isn't that useful providing a bootstrapped ClojureScript is desirable. We've been working on that slowly for a long time now. In the coming months you'll see changes such that the ClojureScript compiler can itself be compiled into JavaScript.
Think about where you would use CLJS - my use cases would not have an issue with extra 100kb of code - you don't use CLJS to do jQuery animations on your web page - you would use it to build complex single page apps or write server side code/scripts.
You don't use clojure for performance anyway, it's going to be slower by default (because of immutability/persistent data structures, and yeah I know about react benefits with immutability that's not my point - you're still going trough a lot more memory and stressing GC) - you use it to help you deal with your code because of it's semantics.
But in reality last time I tried CLJS I didn't really feel like it delivers on the productivity part and it's mostly because of implementation issues. IMO the decision to implement CLJS on top of Closure compiler and in Clojure (instead of going for a self hosting compiler) was a mistake - you can't overstate the value of REPL and fast iteration in a language like Clojure - and my last attempt to use CLJS the compiler/REPL environment far from what I would consider fast iteration : compiler took forever to start because of JVM and while it could run as a service it needed to be restarted frequently enough that it mattered, REPL was very unstable it would just die randomly - sometimes you'd need to refresh the page, sometimes you'd need to restart the server process. Oh and don't even get me started on the voodoo needed to get the damn thing running - install piggieback, then install austin and then add this weasel thingy then configure the server process all so you can get a halfworking repl and pray it doesn't break because good luck figuring out what's actually going on. Compare this to JS where I just go in to the devtools panel and test my code.
Maybe, but things progressed way further outside of CLJS space. If you told me this 2 years ago when I was in to it I would be jumping right on it - back when people were saying coffescript fixed JS problems :D
Right now JS has persistent datastructure libraries and TypeScript is a huge productivity boost - tooling is top notch - it makes JS manageable, once it gets async/await (which it should in the next couple of months) I'll be pretty happy with JS development story.
I'll miss some niceties like collection operations, homoiconicity and macros but on the other hand I have working optional type checking, excellent tooling and I don't have to code in AST serialization format with macros :D
Interesting. Do you have a link to a very basic "get-started" in this space? Right now, figwheel / om or figwheel / reframe are very quick to get started with (although familiarity definitely plays a part..). Last time I looked at js there were 5 or 6 or so flux implementations competing for mindshare and I had to stumble my way through setting up a project with webpack / babel..
ClojureScript applications start smaller than jQuery so I'm not really sure what you mean. If you're already using jQuery then ClojureScript applications are not large in comparison.
As far as your experiences sounds like a lot of your problems didn't have anything to do with ClojureScript and everything to do with trying to getting overly complicated 3rd party setups going. I've only heard woes from people trying to get piggieback + Cider going. I now recommend that people avoid those entirely for ClojureScript anyway.
I admit ClojureScript did have startup time issues but these were addressed earlier this year. ClojureScript can now compile "Hello, world!" from cold JVM boot in ~1.5 seconds. Of course auto-building has be subsecond for ages. REPL sessions start similarly fast and can go for hours without encountering problems.
ClojureScript may still not be your cup of tea but your complaints are not the sort I hear from users much these days.
This needs to be stressed. Performance in mobile web is already bad enough. If a tool has an optional, manual "improve performance" step, that is bad, it needs to be the default case and it needs to be a good citizen within the environment.
There's very little in the JavaScript world that can't be made to work with ClojureScript. That said it could be made easier and official support for CommonJS and RequireJS is underway thanks to Maria Neise's Google Summer of Code work.
Yes there are additional steps involved for working with the Closure compiler, but in return, you get extremely robust dead-code elimination for your own code and third party code alike.
This turns out to be invaluable in production because most projects only realistically use a handful of functions from utility libraries that tend to be 10s of KBs in size.
Now look at: https://github.com/clojure/clojurescript
And try it: http://himera.herokuapp.com/index.html