nix-overlay/flake.nix

{
  description = "Nix ROS Template";
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    flake-utils.url = "github:numtide/flake-utils";
    ros-flake.url = "github:lopsided98/nix-ros-overlay";
  };

  outputs = { self, nixpkgs, ros-flake, flake-utils }:
    flake-utils.lib.eachDefaultSystem
      (system:
        let
          pkgs = nixpkgs.legacyPackages.${system};
          ros = ros-flake.legacyPackages.${system}.rolling;
        in
        {
          devShells.default = 
            pkgs.mkShell {
              buildInputs = (with ros; [ ros2run rmw-fastrtps-dynamic-cpp xacro gazebo ]);
              RMW_IMPLEMENTATION = "rmw_fastrtps_dynamic_cpp";
              shellHook = ''
                export LD_LIBRARY_PATH=${(with pkgs; lib.makeLibraryPath [ libsodium ])}
              '';
            };
        }
      );
}