.then(Promise.promisifyAll(process1))
    .then(Promise.promisifyAll(process2))
    .then(Promise.promisifyAll(process3))

Shouldn't it be just Promise.promisify[1]. Not that it matters, promisifyAll does the same thing, but also looks for child functions to promisify.

[1] https://github.com/petkaantonov/bluebird/blob/master/API.md#...