The original spec, pretty clearly dislikes the whole HTTP / long poll approach, and I agree, I barely considered anything other than a plain socket (with cJSON to handle the data), it's way simpler than anything else and does *almost* everything needed... only potential extra feature needed, is SSL... So I think a proxy just supporting TCP sockets would do for most miners.
I think you ought to be able to do SSL with just the plain TCP socket - it's just a 'modification' to the socket transport layer. I'm pretty sure that miners that support SSL are doing it this way. Remember, HTTPS != SSL; HTTPS == HTTP on top of SSL-enabled sockets. I suppose the proper term these days is TLS though...
I've looked through a couple of the open source Monero miners today, and everything I've checked just uses plain TCP sockets.
I'm using Claymore for Ethereum and that's stratum+tcp also.
That is interesting to note! Thanks for your reply.
So anecdotally speaking from the evidence presented by 1 response, I can safely say that TCP and SSL+TCP socket streams are all that's needed!
Would love further feedback as well.