error: resolving Git reference 'master': revspec 'master' not found

[zaheerahmad33]

Error:

error:
       … while calling the 'derivationStrict' builtin
         at <nix/derivation-internal.nix>:9:12:
            8|
            9|   strict = derivationStrict drvAttrs;
             |            ^
           10|

       … while evaluating derivation 'my-website-0.1.0'
         whose name attribute is located at /nix/store/ng0wrqwcvl55ka18x3s4r77w9baz5lf2-nixpkgs/nixpkgs/pkgs/stdenv/generic/make-derivation.nix:331:7

       … while evaluating attribute 'nodeModules' of derivation 'my-website-0.1.0'
         at /home/ubuntu/buildNodeModules/fixtures/kitchen_sink/default.nix:18:3:
           17|
           18|   nodeModules = fetchNodeModules {
             |   ^
           19|     packageRoot = ./.;

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: resolving Git reference 'master': revspec 'master' not found

default.nix

let pkgs = import <nixpkgs> {};
bnm = import ~/buildNodeModules { pkgs = pkgs; lib = pkgs.lib; };
inherit (bnm) buildNodeModules fetchNodeModules hooks;
in
pkgs.stdenv.mkDerivation {
  pname = "my-website";
  version = "0.1.0";

  src = ./.;

  nativeBuildInputs = [
    hooks.npmConfigHook
    pkgs.nodejs
    pkgs.nodejs.passthru.python # for node-gyp
    pkgs.npmHooks.npmBuildHook
    pkgs.npmHooks.npmInstallHook
  ];

  nodeModules = fetchNodeModules {
    packageRoot = ./.;
  };
}