{
  pkgs,
  lib,
  fetchurl,
  buildLinux,
  linuxPackagesFor,
  repos,
}:

let
  inherit (builtins) elem;
  inherit (lib) recurseIntoAttrs types versions;

  linuxPackage =
    {
      url ? "mirror://kernel/linux/kernel/v${versions.major version}.x/linux-${version}.tar.xz",
      sha256 ? null,
      src ? (fetchurl { inherit url sha256; }),
      version,
      modDirVersion ? (versions.pad 3 version),
      kernelPatches ? [ ],
      ...
    }@args:
    let
      inherit (builtins) removeAttrs;

      args' =
        {
          inherit
            src
            version
            modDirVersion
            kernelPatches
            ;
        }
        // removeAttrs args [
          "url"
          "sha256"
        ];
      linuxPackage = buildLinux args';
      linuxPackages' = recurseIntoAttrs (linuxPackagesFor linuxPackage);
    in
    linuxPackages';

  surfacePatches =
    {
      patchSrc,
      version,
      patchFn,
    }:
    pkgs.callPackage patchFn {
      inherit (lib) kernel;
      inherit version patchSrc;
    };

  versionsOf =
    version:
    # Provides a list of versions that can be used as an enum option for this full version:
    [
      version
      (versions.majorMinor version)
    ];

  versionsOfEnum =
    version:
    # Provide an enum option for versions of this kernel:
    types.enum (versionsOf version);

  isVersionOf =
    kernelVersion: version:
    # Test if the provided version is considered one of the list of versions from above:
    elem kernelVersion (versionsOf version);

in
{
  inherit
    linuxPackage
    repos
    surfacePatches
    versionsOf
    isVersionOf
    versionsOfEnum
    ;
}