amqp.node has a callback-based API if you don't want to use the promise-based API. But this guy reimplemented it, apparently because he doesn't like promises ("This library solves Issues 1 and 2 if you can put up with promises, but it still didn’t solve Issue 3").
He must really hate promises.
I didn't reimplement because of promises. Neither amqp.node nor node-amqp provided the direct access that I wanted.
The promise vs callback is a minor point as they are both equivalent with promises having a slightly higher overhead. But yes, I do hate promises.