Get typespecs for Code.compile_string() module

Hello! Is it possible to get the typespecs for a module that is compiled at runtime via Code.complie_string()? For example, if I run

compiled_module, _bytecode = Code.compile_string(
  """
  defmodule UserDefinedGreeter do
    @spec call(name :: String.t()) :: {:return, String.t()}
    def call(name) do
      {:return, "Hey " <> name}
    end
  end
  """
)

I end up with a UserDefinedGreeter module and I can e.g. call UserDefinedGreeter.call("foo"). However, I can’t seem to access that call typespec.

• Code.Typespec.fetch_types(UserDefinedGreeter) returns :error
• Kernel.Typespec.beam_specs(UserDefinedGreeter) returns nil

Is there an option I’m overlooking, or a different way to compile Elixir code at runtime that will result in the typespecs being accessible?