nix-shell: add shell.nix

shell.nix

@@ -0,0 +1,36 @@
+with import <nixpkgs> { };
+
+let
+  pythonPackages = python3Packages;
+in pkgs.mkShell rec {
+  name = "impurePythonEnv";
+  venvDir = "./venv";
+  buildInputs = [
+    git
+    lsb-release
+    ethtool
+
+    # A Python interpreter including the 'venv' module is required to bootstrap
+    # the environment.
+    pythonPackages.python
+
+    # This execute some shell code to initialize a venv in $venvDir before
+    # dropping into the shell
+    pythonPackages.venvShellHook
+
+  ];
+
+  # Run this command, only after creating the virtual environment
+  postVenvCreation = ''
+    unset SOURCE_DATE_EPOCH
+    pip install -r requirements.txt
+  '';
+
+  # Now we can execute any commands within the virtual environment.
+  # This is optional and can be left out to run pip manually.
+  postShellHook = ''
+    # allow pip to install wheels
+    unset SOURCE_DATE_EPOCH
+  '';
+
+}