Here's the extra poor man's version to get ya'll started. It doesn't have any of the auth/rate limiting/etc or pubsub, but it should basically work for the MPMC queue stuff:

https://github.com/patchbay-pub/patchbay-simple-server

Note that this will leak memory since there's no logic for removing old unused channels.

I did one too -- https://github.com/edoceo/httpubsub

And, a bit late, me too, of the pub/sub option that sounded more appealing to me. https://github.com/olup/patchcreek