anchor.diff:      Config.
   
   prerequisites() ->
  -    [ 
  +    [
        { "docker in $PATH?",
          fun (_Config) ->
                  {done, 0, <<"Docker", _/bytes>>} = erlsh:oneliner("docker -v")
  
positive.code:     catch _:Reason ->
          ct:fail("~ts failed: ~p", [Name, Reason])
      end.
  
negative.code: %%
  
  docker_linux(_) ->
      Name = container_name("docker-linux-"),
      Fdlink = erlsh:fdlink_executable(),
      Args = [which("docker"), "run", "-t", "--rm", "--name", Name, "erlang:19-slim", "bash"],
      ContainerPort = erlang:open_port({spawn_executable, Fdlink}, [stream, exit_status, {args, Args}]),
      try
          ct:fail("not implemented yet")
      after
          sh("docker stop " ++ Name)
      end.
  
  %%
  %% Helpers
  