When cross-posting to both LessWrong and substack, I follow the workflow of copy pasting the LW post into substack. This mostly works, but (very annoyingly) footnotes don't transfer. I've been using this slightly insane (claude-written) script that uses playwright to automatically fix footnotes after copy-pasting into substack. (Your results may vary...)
One note: It's easy to accidentally also copy the sidenotes so you get two copies of the footnotes and this breaks the script. Don't do this (or remove the sidenotes copy). The footnotes should get copied as a single numbered list at the bottom for this to work without issues.
If the LW team wanted, they could try to make a less insane approach, I think this is a common pain point (both directions of cross posting).
I have a firm rule of single source of truth. For any given post / article, I have 1 (one) file in which I write the post. I generally write in markdown, with a couple small added conveniences. Then if there's some way that I want to post it (personal blog, google doc, email, LW, https://berkeleygenomics.org/Explore, pdf), I have a script for that type of post. The scripts are somewhat of a mess, but not that bad, and this hullaballoo makes it fairly easy to crosspost and to edit crossposted posts.
Interesting. It seems relatively easy to somehow allow importing Substack posts, but I don't know how I would copy-paste footnotes into the Substack editor. I'll look into what we can do here, but that direction might be quite tricky.
6Brendan Long
I'm not sure if this is any easier, but you could use the LessWrong GraphQL API to download articles in a consistent format. I use it to sync articles to my personal site.
This is the posts query:
[...]
The GraphQL endpoint is https://www.lesswrong.com/graphql.
I think you can also request contents.markdown if you want but I can't test it right now.