Nice name I wonder does it offer an alias domain called @blackmail.com
On one hand it's always good to have new E2EE email to provide competition to the existing big guys (ProtonMail, Tutanota etc.) On another hand I'm concerned about the longevity of such new services, there's no way to ensure my primary email (let's say I make them my primary) will last before I use it for my important emails.
Just my 2 cent. That aside I really like their minimalist approach!