Describe the bug

👋🏻 Hey Nix-ers!

Another day - another report. I am building minimal LXC container images based on NixOS and I am striving to reduce the final image size as much as possible for some of them. In the process I have noticed that systemd package as provided can be shrunk by disabling some of the optional flags (withRemote, withImportd, withCryptsetup, withHomed, etc) which I take advantage of. However, some of the optional dependencies are not exposed as such, for example kmod, audit, pam, acl or libidn2 to name a few. Instead they are hardcoded in the buildInputs and their options are forcefully set to true. I think it would be great to provide more configurability and expose flags for all these features.

Steps To Reproduce

Steps to reproduce the behavior:
not applicable

Expected behavior

I would love to have an ability to disable some additional optional features using something like withLibidn2, withAudit, withKmod, etc flags.

Screenshots

not applicable

Additional context

not applicable

Notify maintainers

@flokli @kloenk @Mic92 please do let me know if that is a bad idea 😉

Metadata

Please run nix-shell -p nix-info --run "nix-info -m" and paste the result.

[root@nixos:~]# nix-shell -p nix-info --run "nix-info -m"
 - system: `"x86_64-linux"`
 - host os: `Linux 5.15.85-1-pve, NixOS, 23.05 (Stoat), 23.05pre454549.545c7a31e5d`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.13.2`
 - channels(root): `"nixos"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`