libgbm: "undefined variable libgbm" after a nix flake update

[SpidFightFR]

Nixpkgs version

• Stable (24.11)

Describe the bug

I ran a nix flake update on my system this morning, just to see that it now refuses to build:

Steps to reproduce

1. nix flake update
2. sudo nixos-rebuild build --flake .

Expected behaviour

It should build, i assume libgbm is linked to mesa...?

Screenshots

No response

Relevant log output

warning: Git tree '/home/spid/Téléchargements/gitclones/vs-flakes-production' is dirty
error:
       … while calling the 'head' builtin
         at /nix/store/qjmsdak7fhqc7pi922i2mgm45f7af9h8-source/lib/attrsets.nix:1574:11:
         1573|         || pred here (elemAt values 1) (head values) then
         1574|           head values
             |           ^
         1575|         else

       … while evaluating the attribute 'value'
         at /nix/store/qjmsdak7fhqc7pi922i2mgm45f7af9h8-source/lib/modules.nix:816:9:
          815|     in warnDeprecation opt //
          816|       { value = addErrorContext "while evaluating the option `${showOption loc}':" value;
             |         ^
          817|         inherit (res.defsFinal') highestPrio;

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/qjmsdak7fhqc7pi922i2mgm45f7af9h8-source/nixos/modules/system/activation/top-level.nix':

       … while evaluating the option `warnings':

       … while evaluating definitions from `/nix/store/qjmsdak7fhqc7pi922i2mgm45f7af9h8-source/nixos/modules/system/boot/systemd.nix':

       … while evaluating the option `systemd.services.home-manager-spid.serviceConfig':

       … while evaluating definitions from `/nix/store/b14bsz5z288ycfy29y17dvfb4kq66a6r-source/hosts/modules/users.nix':

       … while evaluating the option `home-manager.users.spid.home.file."/home/spid/.config/fontconfig/conf.d/10-hm-fonts.conf".source':

       … while evaluating definitions from `/nix/store/m7snw2xbfxcixggpijla0kpixbslb5cg-source/modules/files.nix':

       … while evaluating the option `home-manager.users.spid.home.file."/home/spid/.config/fontconfig/conf.d/10-hm-fonts.conf".text':

       … while evaluating definitions from `/nix/store/m7snw2xbfxcixggpijla0kpixbslb5cg-source/modules/misc/xdg.nix':

       … while evaluating the option `home-manager.users.spid.xdg.configFile."fontconfig/conf.d/10-hm-fonts.conf".text':

       … while evaluating definitions from `/nix/store/m7snw2xbfxcixggpijla0kpixbslb5cg-source/modules/misc/fontconfig.nix':

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: undefined variable 'libgbm'
       at /nix/store/4falq6wvp826qjfa001z9zrkyfpdbqkf-source/flake.nix:43:11:
           42|           libva
           43|           libgbm
             |           ^
           44|           vulkan-loader

Additional context

No response

System metadata

• system: "x86_64-linux"
• host os: Linux 6.13.5, NixOS, 24.11 (Vicuna), 24.11.20250307.20755fa
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.24.12
• nixpkgs: /nix/store/l75sdw6vydkwaa6cfrf33h2pnzikpxm8-source

Notify maintainers

@K900 @primeos

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[K900]

This is some sort of external flake. 24.11 doesn't have a separate libgbm package, so the flake needs to account for that.

[SpidFightFR]

Alright, thanks ! have a nice day!

[fisuri]

what should I do about this error?

[K900]

What error? Are you getting the exact same trace? If yes, one of your external flakes needs to be fixed to work on 24.11.

[SpidFightFR]

Alright, sorry for the ping, the error is linked to the zen-browser flake. It's not on on you guys, sorry for the disturbance, i'm checking with the zen-browser flake team.

(ref: 0xc000022070/zen-browser-flake#30)

[SpidFightFR]

As of now: problem is solved.

TL;DR: Zen-browser is linked to nixpkgs-unstable, and i was using nixpkgs (24.11).