OP here. thanks for all the comments. some more info:
rmkit is a library (and group of devs) for creating apps on the rM (and now Kobo). outside of rmkit, people typically use Qt to write apps, but there's many routes[0], including SAS[1]: a solution that uses unix pipes. the rM2 requires a bit more hacking to get working than the rM1 because their framebuffer driver[2] is embedded in their software for rM2 and requires updating rm2fb every time remarkable releases a new update. there's alternative drivers[3] to drive the display in development.
i will keep updating the article based on feedback, thank you and keep hacking
[0]: https://remarkable.guide/devel/index.html
[1]: https://rmkit.dev/apps/sas
as long as you have SSH keys and you don't blow away your home partition, you are mostly fine. you do need a slightly older version of Xochitl, though (3.2 and below)