alt Hacker Newsfun fact: clojurescript had support for asynchronous paradigm through core.async library (CSP style) long before async/await landed in javascript itself.
edit: i'm in no way trying to diminish the value of this release, just pointing out how cool it is that you can get new language features before they are available in the host language by just adding a library to your dependencies. clojure is awesome!
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True, but there are many reasons to avoid core.async, especially in 2026.
It balloons up the Js artifact, has no inherent error model, and transforms into state machine code that's hard to read/debug if something goes wrong. Plus, the `go` macro encourages overly-large functions, because it can't transform code outside its own sexpr.
As one Cognitect put it, "core.async is beautiful nonsense".
> fun fact: clojurescript had support for asynchronous paradigm through core.async library (CSP style) long before async/await landed in javascript itself.
Definitely. I was heavily using it and it worked: a few quirks but we did have async/await since more than a decade. I think I discovered it after watching a talk by David Nolen.
Since then I moved to minimal JavaScript on the front-end: SSE is one-way and that is beautiful. I'm glad to see many devs, from a great many different languages, now getting interested in SSE.
Here's a great, recent, talk by David Nolen called "A ClojureScript Survival Kit":
https://youtu.be/BeE00vGC36E
I cannot thanks David "Swannodette" Nolen enough for all the work he did on ClojureScript (and core.async) since its inception. And what's amazing in this talk is that he's actually excited at the idea that we may do away with ClojureScript and use pure Clojure (on the server-side) and server-side events, with just a tiny of JavaScript.
The real demo starts around 26:30. He shows a Webapp running on the client and how much resources it's using, then he shows the exact same Webapp running on the server and pushed one-way to the client using SSE. It is wild: resources usage drops to near zero.
YMMV but I find it easier to reason about my webapps and manage state now that I'm using a minimal DOM morphing lib: I used to have two REPLs (one for Clojure, one for ClojureScript) and lots of back-and-forth traffic and hard-to-track / reproduce state. Now everything is definitely snappier and way easier to reproduce.
I'm not saying SSE is going to work in every case though: YMMV. But in any case the video or at the very least the demo starting @ 26:30 is very much worth watching.