Trying to package brscan3

I’ve started packaging brscan3 (Brother scanner driver e.g. for MFC-7440N) and got stuck:

I’m new to nixos, actually for now I’m doing all this as demo user in a VirtualBox.
After cloning nixpkgs I created a brscan3 next to brscan4/5 and modified whatever seemed to be required.

Not functional yet

  • driver build (pkgs/applications/graphics/sane/backends/brscan3)
  • config (nixos/modules/services/hardware/sane_extra_backends/brscan3.nix)
  • deal with hard coded paths in /nix/store/-brscan3-0.2.13-1/lib/sane/
    potential solution: Replacing hard coded paths in ELF binaries - tape software

Any help/advice/review is welcome!