{ description = "A Nix-flake-based Ruby development environment"; inputs = { flake-utils.url = "github:numtide/flake-utils"; nixpkgs.url = "github:NixOS/nixpkgs"; }; outputs = { self, flake-utils, nixpkgs }: flake-utils.lib.eachDefaultSystem (system: let pkgs = import nixpkgs { inherit system; }; inherit (pkgs) mkShell; ruby = pkgs.ruby_3_1; in { devShells = { default = mkShell { buildInputs = [ ruby ]; shellHook = '' ${ruby}/bin/ruby --version ''; }; }; }); }