I've seen lots of metrics to decide if an open source project is alive: age of bugs, number of pull requests open, number of commits in a time period.
When choosing libraries, I've realised I only look at the last commit time. That's sufficient activity IME.
miniblog.
Related Posts
Programming is a team activity: the vast majority of projects have multiple contributors. Yet all the films I've seen show a solo programmer at a keyboard.
Have any movies got this right?
Activity trackers now exist for animals too! Whistle is a Fitbit-style exercise monitor plus GPS tracker for dogs: https://www.wired.com/review/review-whistle-3-pet-tracker/
Ambient computing is becoming progressively more common.
I'm averaging 3 blog posts/year. It's still a hugely worthwhile activity.