Shaving Your RTT with TCP Fast Open

Regarding client support, why does only Google appear to be interested? Talking about saving a round trip here...

To try with NGINX, you may need to add compile it with --with-cc-opt="-DTCP_FASTOPEN=[X]" otherwise just adding fastopen=23 into your server block may be problematic. https://www.ruby-forum.com/topic/5392464