Thanks! I definitely will add more examples to the landing page, currently I'm working hard on the decks: pathlib in depth, a tour of the stdlib and Norvig's tricks (a collection of tricks from the Pytydes of Peter Norvig).
I believe the hardest part of using spaced repetition to learn programming is creating good decks, it's a ton of work.
It's weird you didn't find the sign-up box to the waitlist, this is how it should look like: https://imgur.com/a/0ZIbz4p, I actually got some sign-ups from this comment!
Any chance you are open sourcing the web app? I can see it being a popular way for niches to show flashcards eg. for students to learn X