gistfile1.exs

opts = [hostname: "localhost", username: "postgres", database: "geo_postgrex_test"]
{:ok, pid} = Postgrex.Connection.start_link(opts)

** (EXIT from #PID<0.127.0>) exited in: GenServer.call(Postgrex.TypeServer, {:fetch, {'localhost', 5432, "geo_postgrex_test", []}}, 60000)
    ** (EXIT) no process
    
    [error] GenServer #PID<0.131.0> terminating
Last message: {:tcp, #Port<0.5421>, <<82, 0, 0, 0, 8, 0, 0, 0, 0, 83, 0, 0, 0, 22, 97, 112, 112, 108, 105, 99, 97, 116, 105, 111, 110, 95, 110, 97, 109, 101, 0, 0, 83, 0, 0, 0, 25, 99, 108, 105, 101, 110, 116, 95, 101, 110, 99, 111, ...>>}
State: %{backend_key: nil, bootstrap: false, extensions: [{Postgrex.Extensions.Binary, nil}, {Postgrex.Extensions.Text, nil}], listener_channels: #HashDict<[]>, listeners: #HashDict<[]>, opts: [hostname: "localhost", username: "postgres", database: "geo_postgrex_test"], parameters: %{}, portal: nil, queue: {[%{command: {:connect, [hostname: "localhost", username: "postgres", database: "geo_postgrex_test"]}, from: nil, reply: :no_reply}], []}, rows: [], sock: {:gen_tcp, #Port<0.5421>}, state: :auth, statement: nil, tail: "", types: :types_removed, types_key: {'localhost', 5432, "geo_postgrex_test", []}}
** (exit) an exception was raised:
    ** (ErlangError) erlang error: {:noproc, {GenServer, :call, [Postgrex.TypeServer, {:fetch, {'localhost', 5432, "geo_postgrex_test", []}}, 60000]}}
        (elixir) lib/gen_server.ex:356: GenServer.call/3
        lib/postgrex/protocol.ex:34: Postgrex.Protocol.bootstrap/1
        lib/postgrex/connection.ex:417: Postgrex.Connection.new_data/2
        lib/postgrex/connection.ex:292: Postgrex.Connection.handle_info/2
        (stdlib) gen_server.erl:593: :gen_server.try_dispatch/4
        (stdlib) gen_server.erl:659: :gen_server.handle_msg/5
        (stdlib) proc_lib.erl:237: :proc_lib.init_p_do_apply/3

I'm having the same problem. Did you manage to fix this?