Не могу запустить пример на Elixir

defmodule MyApp.MixProject do
  use Mix.Project

  def project do
    [
      app: :my_app,
      version: "0.1.0",
      elixir: "~> 1.14",
      start_permanent: Mix.env() == :prod,
      deps: deps()
    ]
  end

  # Run "mix help compile.app" to learn about applications.
  def application do
    [
      #extra_applications: [:logger],
      applications: [:maru] 
    ]
  end

  # Run "mix help deps" to learn about dependencies.
  defp deps do
    [
      {:maru, "~> 0.13"},
      {:cowboy, "~> 2.3"},
      {:jason, "~> 1.0"},
    ]
  end
end

use Mix.Config

# config/config.exs
config :my_app, MyAPP.Server,
  adapter: Plug.Adapters.Cowboy2,
  plug: MyAPP.API,
  scheme: :http,
  port: 8880

config :my_app,
  maru_servers: [MyAPP.Server]

defmodule MyAPP.Server do
  use Maru.Server, otp_app: :my_app
end

# Add MyAPP.Server to Your Supervisor Tree
defmodule MyAPP.Supervisor do
  use Supervisor

  def init(_arg) do
    children = [
      MyAPP.Server
    ]

    Supervisor.init(children, strategy: :one_for_one)
  end
end
defmodule MyAPP.Router.Homepage do
    use MyAPP.Server

    get do
      json(conn, %{ hello: :world })
    end
  end

  defmodule MyAPP.API do
    use MyAPP.Server

    mount MyAPP.Router.Homepage

    rescue_from :all do
      conn
      |> put_status(500)
      |> text("Server Error")
    end
  end

my_app ➤ iex -S mix                                                                                                                                                                                                                  
Erlang/OTP 25 [erts-13.1.5] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [jit:ns]

Generated my_app app
Interactive Elixir (1.14.0) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)>