You can run yarn shadow-cljs compile app to make server.js in your directory.
For testing type yarn shadow-cljs watch app and run node server in a separete terminal window.
This project is imitating the https://github.com/SocketCluster/socketcluster/tree/master/app library app folder,
only it is translated to clojurescript.
Thanks to https://gist.github.com/jjsullivan5196/0904057a2ec3eb080de5c4d6f45da630 for making this possible.