I've been using Readwise.io for years to revisit my Kindle highlights and I find spaced repetition helps remember high-level ideas from books I've read in the past.

A specific book I've highlighted is Aurelien Geron's Hands-On Machine Learning Book. It's a great way to revisit machine learning concepts I want to interiorize and I had been thinking of turning those into flash cards. I may try Mochi Cards for that.

I's also note that spaced repetition in any form requires great dedication. In the case of Readwise, it's somewhere from one to four minutes to read about five daily quotes.