My concern with the server side of this would be a bug in OpenSSL (which I assume this uses) could give a hacker access to the memory space of all current connections, a feature the default forking servers don&#x27;t have to worry about. It&#x27;s a benefit that helped qmail remain secure for so long.<p>And yet I say this as a creator of an async SMTP server, so I don&#x27;t think these days it is <i>that</i> big of an issue.