{
  description = "ToDooDoo";
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";

    treefmt-nix = {
      url = "github:numtide/treefmt-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };
  outputs =
    {
      self,
      nixpkgs,
      treefmt-nix,
    }:
    let
      supportedSystems = [ "x86_64-linux" ];
      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
      pkgsFor = system: (import nixpkgs { inherit system; });
    in
    {
      formatter = forAllSystems (
        system: (treefmt-nix.lib.evalModule (pkgsFor system) ./treefmt.nix).config.build.wrapper
      );
      packages = forAllSystems (
        system:
        let
          pkgs = pkgsFor system;
        in
        {
          default = pkgs.callPackage ./default.nix { inherit pkgs; };
        }
      );
      devShells = forAllSystems (
        system:
        let
          pkgs = pkgsFor system;
        in
        {
          default = pkgs.callPackage ./shell.nix { inherit pkgs; };
        }
      );
    };
}