{
  description = "Reproducible Environment for anish.lakhwara.com";

  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};
        hpi = pkgs.python39Packages.buildPythonPackage rec {
          pname = "HPI";
          version = "v0.3.20220202";
          src = pkgs.fetchgit {
            rev = "e750666e30e8987f3a4c46755857dc85dd64446c";
            url = "https://github.com/karlicoss/HPI";
            sha256 = "sha256-CHrlVG7H2Gzhc2gcAOwWNSivje9K3/tJYA7BQWvSyuQ=";
            leaveDotGit = true;
          };

          nativeBuildInputs = [ python-with-my-packages pkgs.git ];
          propagatedBuildInputs = [ python-with-my-packages ];

          doCheck = false;
          pythonImportsCheck = [ "my.core" ];

          meta = with pkgs.lib; {
            description = "";
            homepage = "https://github.com/karlicoss/HPI";
            # license = with licenses; [ mit ];
            maintainers = with maintainers; [ chickensoupwithrice ];
          };
        };
        python-with-my-packages = pkgs.python39.withPackages (p: with p; [
          pytz # even though it's not needed by the core, it's so common anyway...
          appdirs # very common, and makes it portable
          more-itertools # it's just too useful and very common anyway
          decorator # less pain in writing correct decorators. very mature and stable, so worth keeping in core
          click
          setuptools-scm
          pytest
          geopy
          mypy
        ]);
      in
      {
        devShell = pkgs.mkShell {
          buildInputs = [
            python-with-my-packages
            hpi
          ];
          shellHook = ''
            PYTHONPATH=${python-with-my-packages}/${python-with-my-packages.sitePackages}
            # This only works when you have ~/vimwiki locally, since I'm not putting my unfiltered kitaab online
            alias build='python3 src/kitaab-public/main.py'
            # maybe set more env-vars
          '';
        };
        defaultPackage = hpi;
      });
}