Notes on bisecting nix stuff

i felt git’s bisect feature is pretty useful when using NixOS, so i gathered some notes for a few common cases (with thanks to earlier threads on the topic here).
i was wondering if we could maybe better highlight this topic at say the wiki as well, but i guess my notes here seemed maybe more aimed at the gist format, so i figured maybe i could first post them here.

edit: i now converted this to wiki format


One additional simple thing that can be really helpful is the --first-parent flag to git bisect. It makes it so that you mostly only land on merge commits into master, which means most things should be cached in Hydra.

I think I originally learned about this from What commits belong to which channel - #7 by vcunat.