I have noticed that devShells evaluates all nixosConfigurations, if you refer to checks from outputs:

# devShell.nix
pkgs: pkgs.mkShell {
  packages = [
    outputs.checks.${pkgs.system}.pre-commit-check.enabledPackages
  ];
}

# checks.nix
{
  checks.pre-commit-check = {
    inputs,
    system,
    ...
  }:
    inputs.git-hooks.lib.${system}.run {
      src = ./.;
      hooks = {
        alejandra.enable = true;
        statix.enable = true;
        ruff-format.enable = true;
      };
    };
}

I have noticed that devShells evaluates all nixosConfigurations, if you refer to checks from outputs:

# devShell.nix
pkgs: pkgs.mkShell {
  packages = [
    outputs.checks.${pkgs.system}.pre-commit-check.enabledPackages
  ];
}

# checks.nix
{
  checks.pre-commit-check = {
    inputs,
    system,
    ...
  }:
    inputs.git-hooks.lib.${system}.run {
      src = ./.;
      hooks = {
        alejandra.enable = true;
        statix.enable = true;
        ruff-format.enable = true;
      };
    };
}

The offending code is in builtinModules/nixosConfigurations.nix:

      checks = foldl recursiveUpdate { } (mapAttrsToList
        (n: v: {
          # Wrapping the drv is needed as computing its name is expensive
          # If not wrapped, it slows down `nix flake show` significantly
          ${v.config.nixpkgs.system}."nixos-${n}" = v.pkgs.runCommand
            "check-nixos-${n}"
            { } "echo ${v.config.system.build.toplevel} > $out";
        })

The offending code is in builtinModules/nixosConfigurations.nix:

      checks = foldl recursiveUpdate { } (mapAttrsToList
        (n: v: {
          # Wrapping the drv is needed as computing its name is expensive
          # If not wrapped, it slows down `nix flake show` significantly
          ${v.config.nixpkgs.system}."nixos-${n}" = v.pkgs.runCommand
            "check-nixos-${n}"
            { } "echo ${v.config.system.build.toplevel} > $out";
        })
        configs);

In reply to @niclas:overby.me
I'm still not sure why the check is needed in the first place?
It seems to be a performance footgun with projects with many nixosConfigurations.

I havent tested this, but heres what i'd do for integrating git-hooks.nix:

{ src, lib, config, ... }: {
  options.git-hooks = {
    type = lib.types.attrs;
    default = { };
  };

  config = {
    withOverlays = [
      (final: prev: {
        pre-commit-check = final.inputs.git-hooks.lib.${final.system}.run
          ({ inherit src; } // config.git-hooks);
      })
    ];

    checks = pkgs: { inherit (pkgs) pre-commit-hook; };

    devShell = { pre-commit-check, ... }: {
      inherit (pre-commit-check) shellHook;
      packages = pre-commit-check.enabledPackages;
    };
  };
}

can put that as nix/flakelightModules/git-hooks.nix or w/e and import the module in your flakelight config. (or if you have many repos, put this in your common config one)

Then in a flake you can use it as such:

{
  inputs = {
    flakelight.url = "github:nix-community/flakelight";
    git-hooks.url = "github:cachix/git-hooks.nix";
  };
  outputs = { flakelight, ... }@inputs: flakelight ./. {
    inherit (inputs);
    # Pull it from file, outputs.flaklightModules.git-hooks,
    # inputs.shared-flake.flakelightModules.git-hooks, or w/e
    imports = [ ./git-hooks.nix ];

    git-hooks.hooks = {
      alejandra.enable = true;
      statix.enable = true;
      ruff-format.enable = true;
    }
  };
}

You'd even be able to autoload it as nix/git-hooks.nix:

{
  hooks = {
    alejandra.enable = true;
    statix.enable = true;
    ruff-format.enable = true;
  };
}