{
  description = "Infinsweeper";

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

  outputs =
    { nixpkgs, ... }:
    let
      system = "x86_64-linux";
      pkgs = nixpkgs.legacyPackages.${system};

      ruby = pkgs.ruby.withPackages (
        p: with p; [
          sqlite3
          sequel
          rackup
          puma
          sinatra
        ]
      );

      app = pkgs.stdenv.mkDerivation {
        pname = "infinsweeper";
        version = "0.1.0";
        src = ./.;
        buildInputs = [ ruby ];
        installPhase = ''
          mkdir -p $out
          cp -r . $out/
        '';
        postFixup = ''
          substituteInPlace $out/bin/infinsweeper \
            --replace-fail '#!/usr/bin/env ruby' '#!${ruby}/bin/ruby'
        '';
      };
    in
    {
      packages.${system}.default = app;

      devShells.${system}.default = pkgs.mkShell {
        packages = [
          ruby
          pkgs.sqlite
        ];
      };
    };
}