Metosin usually say they are using the libraries in their own production projects. Sieppari is quite a small library for optimized interceptors but I don't know if you really need that kind of speed and clj/cljs reach - if you do - try it out. it put some more contraints on the interceptor functions handling of the context data than the pretty open-ended pedestal interceptors. regarding eines I did not know about it. For reference, checkout replikativ/kabel which is websocket based as well, and backs the communication of that interesting project. https://github.com/replikativ/kabel and of course also sente, which is a common websocket library. I found it problematic to use a few years ago because it wasnt easily dropped right into pedestal.

@UQY3M3F6D Thanks for sharing. I think for now, I'm going to go with Aleph/Manifold. My middleware/interceptor needs are low, my websocket needs are simple, but my need for hardcore async processing on the server is really high.