Flake errors when trying to hack on kernel modules

1

I have been trying to follow this guide to get started hacking on kernel modules in NixOS https://blog.thalheim.io/2022/12/17/hacking-on-kernel-modules-in-nixos/.

But unfortunatelly i get stuck at

$ nix develop /home/myname/flake#nixosConfigurations.nixhpix.boot.kernel
error: flake 'git+file:///myname/oskar/flake' does not provide attribute 'devShells.x86_64-linux.nixosConfigurations.nixhpix.boot.kernel', 'packages.x86_64-linux.nixosConfigurations.nixhpix.boot.kernel', 'legacyPackages.x86_64-linux.nixosConfigurations.nixhpix.boot.kernel' or 'nixosConfigurations.nixhpix.boot.kernel'

It seems to me like the nix command / flakes have changed since the tutorial was written. Is it possible to do the same thing (i.e., get a development shell from a derivation) with a different syntax today?

2

Read the command again, you’re missing a config.

3

Yea sorry that was a copy pasta error and I tried the correct version earlier as well but it still does not work for me

[23:19:29] ❯ nix develop ".#nixosConfigurations.nixhpix.config.boot.kernel"
warning: Git tree '/home/oskar/flake' is dirty
error: flake output attribute 'nixosConfigurations.nixhpix.config.boot.kernel' is not a derivation or path

Does it work for you? Fish can autocomplete it, so I do not think I have misspelled something more and it should exist as a flake attribute.

4

No, but frankly, I don’t think that blog post could ever have worked. It maps to the boot.kernel config option. There is a package for the kernel in boot.kernelPackages.kernel, though, try:

nix develop .#nixosConfigurations.nixhpix.config.boot.kernelPackages.kernel
5

Thank you! That seemed to work better at least!