nix environment for js

flake.lock

{
  "nodes": {
    "flake-utils": {
      "locked": {
        "lastModified": 1637014545,
        "narHash": "sha256-26IZAc5yzlD9FlDT54io1oqG/bBoyka+FJk5guaX4x4=",
        "owner": "numtide",
        "repo": "flake-utils",
        "rev": "bba5dcc8e0b20ab664967ad83d24d64cb64ec4f4",
        "type": "github"
      },
      "original": {
        "owner": "numtide",
        "repo": "flake-utils",
        "type": "github"
      }
    },
    "nixpkgs": {
      "locked": {
        "lastModified": 1637188321,
        "narHash": "sha256-RN6R9Ar8Ni7gW42u5Te4wgHAY4QEnVALWxZtFC7JHR4=",
        "owner": "nixos",
        "repo": "nixpkgs",
        "rev": "4ae4baa724033663030314a35c89df0aecc05f5b",
        "type": "github"
      },
      "original": {
        "owner": "nixos",
        "repo": "nixpkgs",
        "type": "github"
      }
    },
    "root": {
      "inputs": {
        "flake-utils": "flake-utils",
        "nixpkgs": "nixpkgs"
      }
    }
  },
  "root": "root",
  "version": 7
}

flake.nix

{
  
  nixConfig = {
    bash-prompt-suffix = "[dev]# ";
  };
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs";
    flake-utils.url = "github:numtide/flake-utils";
  };
  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system: 
      let pkgs = nixpkgs.legacyPackages.${system};
  
      in {
        devShell = pkgs.mkShell {
          name = "js-sh";
          buildInputs = with pkgs; [ nodejs-16_x ]; 

          NPM_CONFIG_PREFIX = "/home/u/.npm-packages";
        };
      });
}