Only informal. The author mentions extensive time spent on this since original publication, mentions questions he's responded to or sought more advice on since

Only informal. The author mentions extensive time spent on this since original publication, mentions questions he's responded to or sought more advice on since publication, and I noticed that that last-updated date, near the top, changes from 2-25 to 2-26. It seems to be actively maintained. While I understand HN's preference for no duplicate posts, this seems to have evolved significantly since original posting.