Thanks for the great guide, and I was confused with the Writeable demo: Why the "wait drain" was logged after only one HELLO is logged to stdout, I assume the buffer was empty after the first HELLO logged, the 2nd HELLO should also be logged before the first "wait drain", not sure where did i misunderstood, is this because the stdout.write is async, after calling the "cb", the "hello" in the buffer will be removed?