Koltrix
Startups
The Welcome Email That Earns a Second Login
Your welcome email has one job: bring a new user back for a second session. What to put in it, what to cut, and how to send it the moment someone signs up.
5 min read
AI & emailHow AI email classification works, explained without hype
What an AI email classifier actually looks at, how rules and models split the work, why it gets things wrong, and how to judge one on your own inbox.
5 min read
DeliverabilitySpam filter myths: trigger words, images and link counts
Modern filters care far more about reputation and engagement than single words. Which content folklore is outdated and which content issues still matter.
4 min read