frontend

For anyone curious about Clojure, I'd recommend checking out the CircleCI frontend [0] for an example of a production ClojureScript app. [0] https://github.com/circleci/frontend

Is the new frontend also written in ClojureScript? Seems you've closed sourced the frontend (old source is here https://github.com/circleci/frontend) but you used to use CLJS, but maybe new one is written in something else?

I think business software here means software like: https://github.com/reddit/reddit, https://github.com/circleci/frontend, ERP, e-commerce and so on, against general application like library/framework/language compiler/database/OS

I was the main author of Circle's frontend (the code is open-source: https://github.com/circleci/frontend). I went on to build Precursor (https://precursorapp.com), which uses Datascript (https://github.com/tonsky/datascript) to accomplish a lot of the things that Om Next promises. If you haven't tried Datascript, you should really take a look! It does require a bit of work to make datascript transactions trigger re-renders, but the benefits are huge. It's like the difference between using a database and manually managing files on disk for backend code. My understanding is that Om Next will integrate nicely with Datascript, so you can keep using it once you upgrade. If you're interested in learning more about building UIs with Datascript, I'm giving a talk on Monday at the datomic/datascript meetup: http://www.meetup.com/sf-datomic-datasc

For CircleCi, it's the present. Their frontend is written in Om, a cljs wrapper around React. https://github.com/circleci/frontend https://www.youtube.com/watch?v=LNtQPSUi1iQ

It's much more pleasant to build UIs with lots of different states in React, because you have a full programming language at your disposal. The last js library I worked with was Knockout.js. Having to use Knockout's limited subset of a programming language to do view logic meant that lots of view logic lived in the models. But the really big difference is in using ClojureScript. I converted CircleCI's open-source frontend[1] to Om/React and it feels much closer to backend codebase than a frontend. Brandon Bloom gave a good talk about it at Clojure/West: https://www.youtube.com/watch?v=LNtQPSUi1iQ [1] https://github.com/circleci/frontend

I've been using it in production for a number of applications for about 6 months now and haven't seen any performance issues. Prismatic http://getprismatic.com/ and CircleCI https://circleci.com/ both use ClojureScript for their front-ends. CircleCI open sourced their front-end here https://github.com/circleci/frontend/tree/master/src-cljs/fr... as you can see it's a decent size app, and Prismatic have blogged about Om and performance here http://blog.getprismatic.com/om-sweet-om-high-functional-fro... In general, there should be very little overhead compared to regular JavaScript once the advanced compilation option is used.

Are you doing any kind of throttling on the scroll events? When I was optimizing transitions based on scroll position, I found that pulling the scroll events off of a queue of size 1 was really effective in reducing dropped frames [1]. [1] https://github.com/circleci/frontend/blob/master/src-cljs/fr...

It's definitely not toy stuff... CircleCI's front-end uses ClojureScript, and they recently put the repo up on GitHub for all to see (https://github.com/circleci/frontend).

If you're interested in seeing a complete in-production Om app, check out the CircleCI frontend: http s://github.com/circleci/frontend

They do, and ClojureScript (they're responsible for the largest open-source React/Om ClojureScript app, https://github.com/circleci/frontend). Because of the tech they built to auto-configure projects (and because of circle.yml), they also have statistics on tech usage across companies.