method connect () {
    start {
        my $conn = await IO::Socket::Async.connect($!host, $!port);

        $!incoming = self!process-messages($conn.Supply(:bin)).share;
        say $!incoming;
        my $connected = $!incoming.grep(0xff).Promise;

        say 'done';
        await $connected;
        say 'connected';  #### I never get here.
        $!connection = $conn;
        True
    }
}

method !process-messages($incoming) {
        supply {
            my @chars = '';
            whenever $incoming -> $data {
                emit $data.unpack('H*');
            }
    }
}