I have finished the rspamd chapter, and am what I think will be the last chapter. Unless I break it into two pieces, one social and one technical. Haven’t decided yet.
Sometimes you legitimately need to contact two hundred people with mail run by Microsoft or Google, but suddenly spewing lots of email is a leading indicator of spambot infection. I mail people in the Email Empire every day, but one at a time. When I finish writing this book, however, I’ll have to notify my magnificent sponsors via email. About a third of my sponsors have email addresses backed by Gmail or Microsoft. If I suddenly drop dozens of messages on both of them, they’ll perk up and take a good hard look at my host. Avoiding notice is the best defense.
Postfix normally sends email as fast as the system supports it, but you can deliberately throttle how quickly it sends to select sites. Perhaps sending identical messages to thirty recipients simultaneously will awaken Gmail’s spam guardians, but those same messages one at a time, several seconds or even a minute apart, will pass unnoticed.
The pieces that remain are neither technically innovative, nor do they require extensive research, so I expect to finish soon. If you want to sponsor, now is the time.