Usually I would use Pushshift, but we don't have it anymore. This is done by seeking the subreddit's timeline and using the search feature. Hopefully this covers all of it.
153 (+ me) new contributors, thank you!
Instead of one temporary JSON file, contributors now can submit patches in form of separate files per entry, that will be merged by `merge_out.py` without dealing with the potential conflicts to the main `atlas.json`.