Flake for NodeJS dev

flake.nix

{
  description = "The NodeJS development environment";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, flake-utils, nixpkgs }:
    flake-utils.lib.eachDefaultSystem
      (system:
        let
          pkgs = import nixpkgs {
            inherit system;
            config = {
              allowUnfree = true;
              permittedInsecurePackages = [
                "nodejs-10.24.1"
              ];
            };
          };

          makeNodeEnv = name: node: pkgs.buildEnv {
            inherit name;
            paths = [
              node
              pkgs.yarn
            ] ++ [
              pkgs.gh
              pkgs.sqlite
              pkgs.git
              pkgs.gnumake
            ];
          };

          derivations = rec
          {
            default = derivations.node14;

            node10 = makeNodeEnv "node-10" pkgs.nodejs-10_x;

            node12 = makeNodeEnv "node-12" pkgs.nodejs-12_x;

            node14 = makeNodeEnv "node-14" pkgs.nodejs-14_x;

            node16 = makeNodeEnv "node-16" pkgs.nodejs-16_x;

            node17 = makeNodeEnv "node-17" pkgs.nodejs-17_x;

            node18 = makeNodeEnv "node-18" pkgs.nodejs-18_x;
          };
        in
        {
          packages = derivations;

          devShells = builtins.mapAttrs
            (
              name: env: pkgs.mkShellNoCC {
                inherit name;

                buildInputs = [
                  env
                ];
              }
            )
            derivations;
        }
      );
}

Oh really ?! How come?!