{ inputs = { nixpkgs.url = github:NixOS/nixpkgs/nixos-unstable; utils.url = github:numtide/flake-utils; }; outputs = { nixpkgs, utils, ... }: utils.lib.eachDefaultSystem(system: let pkgs = import nixpkgs { inherit system; }; in { devShell = pkgs.mkShell { nativeBuildInputs = with pkgs; [ rustup ]; buildInputs = with pkgs; [ ]; shellHook = '' rustup toolchain install stable rustup default stable rustup update ''; }; }); }