Hi {{first_name}},
We've been building something for the last {{build_duration}}, and it goes live on {{launch_date}}.
It's {{one_line_description}} — built because {{origin_problem}} kept coming up and nothing we could point people at actually solved it.
There's nothing to click yet. This is just so it doesn't arrive out of nowhere.
Add {{launch_date}} to your calendarWhy it is shaped this way: A teaser with no purchase link is doing something specific: it separates announcement from ask, so launch day arrives as news rather than as a sales email. Naming the problem you were solving is what makes the teaser land — 'something exciting is coming' tells the reader nothing and reads like every other launch email they have ignored.