flake.nix

{
  # https://github.com/nix4cyber/nix4cyber
  description = "nix4cyber";
  inputs.nixpkgs.url = "github:NixOS/nixpkgs";
  outputs = { self, nixpkgs, ... }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs {
        inherit system;
        config.allowUnfree = true;
      };
      utils = import ./utils.nix { inherit pkgs; };

      # Automatically detect directories containing shell.nix files
      isDirectory = path: builtins.pathExists (path + "/shell.nix");

      # Get a list of all entries in the repo root
      allEntries = builtins.attrNames (builtins.readDir ./.);

      # Filter to only include directories that have a shell.nix file
      dirs = builtins.filter (dir:
        builtins.pathExists (./. + "/${dir}/shell.nix")
        && builtins.isAttrs (builtins.readDir (./. + "/${dir}"))) allEntries;

      loadShell = name: {
        inherit name;
        value = import ./${name}/shell.nix {
          inherit pkgs;
          inherit utils;
        };
      };

      shells = builtins.listToAttrs (map loadShell dirs);
      allBuildInputs = builtins.concatLists (map (name:
        (import ./${name}/shell.nix {
          inherit pkgs;
          inherit utils;
        }).nativeBuildInputs or [ ]) dirs);
      combineShellHooks = builtins.concatStringsSep "\n" (map (name:
        let
          shell = import ./${name}/shell.nix {
            inherit pkgs;
            inherit utils;
          };
        in shell.shellHook or "") dirs);
    in {
      lib = { inherit utils; };
      devShells.${system} = shells // {
        all = pkgs.mkShell {
          nativeBuildInputs = allBuildInputs;
          shellHook = combineShellHooks;
        };
      };
    };
}