diff --git a/shell.nix b/shell.nix
index 49264c2..8d72576 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,24 +1,26 @@
-{ pkgs ? import <nixpkgs> { } }:
+{ pkgs ? import (builtins.fetchTarball {
+  name = "nixos-unstable-erambler";
+  url = "https://github.com/nixos/nixpkgs/archive/f9d90fdbbfea5ac0349cd7d5a7025a2434dace1c.tar.gz";
+  sha256 = "14lsfish1sxfbz7sqw8nzvc915j7g3asliqa45hjnpyg35cfslwf";
+}) { } }:
 
 let
-  my_yaspin = pkgs.python38.pkgs.buildPythonPackage rec {
+  python = pkgs.python38;
+  my_yaspin = python.pkgs.buildPythonPackage rec {
     pname = "yaspin";
     version = "1.3.0";
-
-    src = pkgs.python38.pkgs.fetchPypi {
+    src = python.pkgs.fetchPypi {
       inherit pname version;
       sha256 =
         "cc37d35cc7f796dada6c37430b49e471ffa05d0686e6f8de36f83978b732df54";
     };
-
     doCheck = false;
-
     meta = {
       homepage = "https://github.com/pavdmyt/yaspin";
       description = "Yet Another Terminal Spinner for Python";
     };
   };
-  python = pkgs.python38.withPackages (py: [
+  pythonWithPackages = python.withPackages (py: [
     py.python
 
     py.invoke
@@ -42,5 +44,5 @@ let
     py.typogrify
   ]);
 in pkgs.mkShell {
-  buildInputs = with pkgs; [ python zeromq lessc nodejs-14_x yarn ];
+  buildInputs = with pkgs; [ pythonWithPackages zeromq lessc nodejs-14_x yarn ];
 }