Anyone have any ideas/suggestions for playing by post? This game is so exciting to me, but for childcare reasons, most of my free time is either in little pockets or at odd times of the day, which is why it would be neat to be able to do some time-shifting. I wonder if you could do a De Profundis-style game by correspondence?

I think it's a great idea! Like any game with dice it might take a little back-and-forth to get through an Exertion roll, but since it's a one-roll-and-interpret process I think you could handle it in a few chunks. Something like one post to establish "here's what I'm actually doing" and note all the things on your sheet that are giving you dice, a second to handle any Weirding dice/add any additional details to the scene, then a third with the roll result and how you're spending the dice (on success, on keeping your qualities from dropping, etc) and going back to the in-fiction narration from there. Spending points for Ratiocination is simple, just a yes/no on whether you're doing it and how many.

Functionally I don't have any suggestions just because I'm not a big play-by-post person, personally. Somewhere I saw mention of playing in a shared Google Doc, which is something I would have never thought of but might have some cool possibilities for things like inserting images and using the comments to handle "rules stuff" and keeping the main document mostly fictional narrative. Just a thought!