flake.nix

{
  inputs = {
    nixpkgs.url = "github:cachix/devenv-nixpkgs/rolling";
    systems.url = "github:nix-systems/default";
    devenv.url = "github:cachix/devenv";
    devenv.inputs.nixpkgs.follows = "nixpkgs";
  };

  inputs.fenix.url = "github:nix-community/fenix";
  inputs.fenix.inputs = { nixpkgs.follows = "nixpkgs"; };

  nixConfig = {
    extra-trusted-public-keys = "devenv.cachix.org-1:w1cLUi8dv3hnoSPGAuibQv+f9TZLr6cv/Hm9XgU50cw=";
    extra-substituters = "https://devenv.cachix.org";
  };

  outputs = { self, nixpkgs, devenv, systems, ... } @ inputs:
    let
      forEachSystem = nixpkgs.lib.genAttrs (import systems);
    in
      {
      packages = forEachSystem (system: {
        devenv-up = self.devShells.${system}.default.config.procfileScript;
      });

      devShells = forEachSystem
        (system:
          let
            pkgs = nixpkgs.legacyPackages.${system};
          in
            {
            default = devenv.lib.mkShell {
              inherit inputs pkgs;
              modules = [
                {
                  # https://devenv.sh/reference/options/
                  packages = [ pkgs.hello ];

                  languages.rust.enable = true;
                  languages.rust.channel = "stable";
                }
              ];
            };
          });
    };
}