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

  outputs = { self, nixpkgs }: let
    systems = [
      "x86_64-linux"
      "x86_64-darwin"
      "aarch64-linux"
      "aarch64-darwin"
      "armv7l-linux"
    ];
    forAllSystems = f: nixpkgs.lib.genAttrs systems (system: let
      pkgs = import nixpkgs {
        inherit system;
        overlays = [
          (final: prev: {
            vcpkg-tool = final.callPackage ./nix/packages/vcpkg-tool/package.nix { };
            vcpkg = import ./nix/packages/vcpkg/package.nix { inherit (prev) vcpkg; };
          })
        ];
      };

    in f system pkgs);
    inherit (nixpkgs) lib;
  in {
    packages = forAllSystems (system: pkgs: {
      default = self.packages.${system}.test;
      test = pkgs.callPackage ./nix/packages/test/package.nix {
        src = ./.;
      };

      test-aarch64 = pkgs.pkgsCross.aarch64-multiplatform.callPackage ./nix/packages/test/package.nix {
        src = ./.;
      };

      test-armv7 = pkgs.pkgsCross.armv7l-hf-multiplatform.callPackage ./nix/packages/test/package.nix {
        src = ./.;
      };
    });

    devShells = forAllSystems (system: pkgs: {
      default = self.devShells.${system}.vcpkgVendoredLibs;

      vcpkgVendoredLibs = pkgs.mkShell {
        nativeBuildInputs = with pkgs; [
          vcpkg
          cmake
        ];

        env = {
          VCPKG_ROOT = "${pkgs.vcpkg}/share/vcpkg";
        };
      };

      nixVendoredLibs = pkgs.mkShell {
        nativeBuildInputs = with pkgs; [
          cmake
        ];
        buildInputs = with pkgs; [
          nlohmann_json
          fmt
        ];
      };
    });
  };
}