{
  inputs = {
    flake-utils.url = "github:numtide/flake-utils";
    naersk.url = "github:nix-community/naersk";
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
  };

  outputs = { self, flake-utils, naersk, nixpkgs }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = (import nixpkgs) { inherit system; };

        naersk' = pkgs.callPackage naersk { };

      in rec {
        # For `nix build` & `nix run`:
        packages.default = naersk'.buildPackage {
          src = ./.;
          nativeBuildInputs = with pkgs; [ pkg-config openssl ];
          GIT_HASH = "000000000000000000000000000000";
        };

        # For `nix develop`:
        devShells.default = pkgs.mkShell {
          nativeBuildInputs = with pkgs; [
            rustc
            cargo
            cargo-watch
            clippy
            rustfmt
            rust-analyzer
            pkg-config

            openssl
          ];
          env = {
            RUST_BACKTRACE = 1;
            RUST_LOG = "debug";
          };
        };
      });
}