{
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    utils.url = "github:numtide/flake-utils";
    poetry2nix = {
      url = "github:nix-community/poetry2nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = {
    self,
    poetry2nix,
    nixpkgs,
    utils,
  }: let
    out = system: let
      pkgs = nixpkgs.legacyPackages."${system}";
      inherit (poetry2nix.lib.mkPoetry2Nix {inherit pkgs;}) mkPoetryApplication;
      python = pkgs.python39;
    in {
      devShell = pkgs.mkShell {
        buildInputs = with pkgs; [
          (python39Packages.poetry.withPlugins (p: [p.poetry-plugin-up]))
          libnotify
        ];
      };

      defaultPackage = mkPoetryApplication {
        inherit python;
        projectDir = ./.;
        # There is no unit tests. Avoid building mypy
        checkGroups = [];
      };

      defaultApp = utils.lib.mkApp {
        drv = self.defaultPackage."${system}";
      };
    };
  in
    with utils.lib; eachSystem defaultSystems out;
}