unpacking 'https://github.com/NixOS/nixpkgs/archive/b4fd65b198c599cbe814fcb9f42d25d021595ec9.tar.gz' into the Git cache...
this derivation will be built:
  /nix/store/64pbdqlps4lvckzblfgli108gd95gfqs-bcachefs-module-7.0.0-38-generic-64k.drv
building '/nix/store/64pbdqlps4lvckzblfgli108gd95gfqs-bcachefs-module-7.0.0-38-generic-64k.drv'...