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

    treefmt-nix = {
      url = "github:numtide/treefmt-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs =
    inputs:
    {
      overlays.default = import ./overlay;
    }
    // (
      let
        system = "x86_64-linux";

        pkgs = import inputs.nixpkgs {
          inherit system;
          config.allowUnfree = true;
          overlays = [ inputs.self.overlays.default ];
        };

        treefmt = inputs.treefmt-nix.lib.evalModule pkgs ./treefmt.nix;
      in
      {
        packages.${system} = pkgs;
        formatter.${system} = treefmt.config.build.wrapper;
        checks.${system}.formatting = treefmt.config.build.check inputs.self;
      }
    );
}