currently patching nixpkgs to build Facebook Sapling for macOS. learned about unstable.host-config and unstable.target-applies-to-host as well as cargo config because they caused the .cargo/config set by the project to be ignored. fun stuff.
unfortunately the binary doesn't do anything, which is baffling, but we can possibly give it to the Sapling devs to look at?
If you know anything about how Sapling works and want to look at a build that doesn't do anything: https://github.com/NixOS/nixpkgs/pull/202754