"failed to scan hardware: unsupported bus type: Host" on nixos-apple-silicon host

[astratagem]

I'm running the command as provided in the readme and am seeing the following:

$ sudo nix run \
        --option experimental-features "nix-command flakes" \
        --option extra-substituters https://numtide.cachix.org \
        --option extra-trusted-public-keys numtide.cachix.org-1:2ps1kLBUWjxIneOy1Ik6cQjb41X0iXVXeHigGmycPPE= \
        github:nix-community/nixos-facter -- -o facter.json
2025/08/01 06:50:50 failed to scan: failed to scan hardware: unsupported bus type: Host

Same result when running the command using nixpkgs#nixos-facter.

With --log-level debug I get:

2025/08/01 06:54:23 facter.go:67: DEBUG building report system=aarch64-linux version=1
2025/08/01 06:54:23 facter.go:74: DEBUG scanning hardware features="[memory pci net serial cpu bios monitor scsi usb prom sbus sys sysfs udev block wlan]"
2025/08/01 06:54:23 root.go:141: failed to scan: failed to scan hardware: unsupported bus type: Host

This is an M2 Apple MacBook Air running NixOS via nix-community/nixos-apple-silicon.

[Mic92]

Is this reproducible in a Linux vm on macOS by chance? I have a mac for testing but not with NixOS.

[astratagem]

@Mic92 I could test that out pretty easily, I'm surrounded by MacBooks. It's been a bit though, I'll probably just use UTM as that's probably quickest to set up. I'll get back to you shortly.

[astratagem]

@Mic92 Here we go, this is Arch Linux via UTM/QEMU on aarch64:

[root@alarm ~]# nix run \
>         --option experimental-features "nix-command flakes" \
>         --option extra-substituters https://numtide.cachix.org \
Oy1Ik6cQjb41X0iXVXeHigGmycPPE= \-public-keys numtide.cachix.org-1:2ps1kLBUWjxIneO
>         github:nix-community/nixos-facter -- -o facter.json
2025/08/06 17:38:22 failed to scan: failed to scan hardware: failed to fetch udev data for device "/sys/devices/pci0000:00/0000:00:03.0/usb1/1-1/1-1:1.0/0003:0627:0001.0001/input/input1" with udev data
: failed to parse usb: failed to parse model id: strconv.ParseUint: parsing "": invalid syntax

Looks like a different error though.

[unhitched9271]

I'm hitting the same error on NixOS fwiw (not Apple hardware, a Surface Pro) - happy to provide further info if needed

[luckie10]

On surface pro 6 I get the following

$ sudo nix run \
  --option experimental-features "nix-command flakes" \
  --option extra-substituters https://numtide.cachix.org \
  --option extra-trusted-public-keys numtide.cachix.org-1:2ps1kLBUWjxIneOy1Ik6cQjb41X0iXVXeHigGmycPPE= \
  github:numtide/nixos-facter -- -o facter.json
2025/12/02 03:38:26 failed to scan: failed to scan hardware: unsupported bus type: Bluetooth

$ sudo nix run nixpkgs#nixos-facter -- -o facter.json --log-level debug
2025/12/02 03:49:35 facter.go:67: DEBUG building report system=x86_64-linux version=1
2025/12/02 03:49:35 facter.go:74: DEBUG scanning hardware features="[memory pci net serial cpu bios monitor scsi usb prom sbus sys sysfs udev block wlan]"
2025/12/02 03:49:36 root.go:141: failed to scan: failed to scan hardware: unsupported bus type: Bluetooth