I believe Sam is a predecessor of Acme[1][2], which still attracts new users today. One of its notable users is Russ Cox, the tech lead of the Golang team. I haven’t used Acme yet, but I want to try it out one day.

If you’re interested in learning more about ed, I highly recommend “Ed Mastery” by Michael W Lucas [3]

[1] https://doc.cat-v.org/plan_9/4th_edition/papers/acme/ [2] https://www.youtube.com/watch?v=dP1xVpMPn8M [3] https://www.amazon.de/gp/product/B07BVBSDNZ