@vaporeon_ without XMPP, maybe? Dovecot + Apache + essential system daemons + kernel would likely push your memory purresure; though purrhaps less so if you aggressively disable potential sources of memory usage in Apache (e.g., cacheing), or if you found a less memory hungry alternative to Dovecot??

if you’re okay with swapping then you might get away with it though, even with an XMPP server. but you’d purrobably swap a lot