{ inputs = { nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable"; flake-utils.url = "github:numtide/flake-utils"; fenix.url = "github:nix-community/fenix"; }; outputs = { self, fenix, flake-utils, nixpkgs }: flake-utils.lib.eachDefaultSystem (system: let pkgs = nixpkgs.legacyPackages.${system}; in { devShells.default = pkgs.mkShell { packages = [ fenix.packages.${system}.complete.toolchain ]; }; }); }