I was kind of expecting to find some open source implementations of Stratum servers.

Seems like all pools are running some proprietary closed source servers. Is that really the case? I hope I am missing something here.

The only FOSS implementations is from Slush, but the last commit is from Dec 2016. https://github.com/slush0/stratum-mining

The other one is from braiins (slush again). https://github.com/braiins/braiins/tree/bos-devel/open/protocols/stratum/src/v1. Is this used by any pools in production?

Any pointers will be really helpful.

Thanks