The underlying query builder - http://knexjs.org - is much more of a 1-to-1 port. Bookshelf shares a number of similar features with eloquent, such as the process of defining relations, and handling eager/nested eager loading, but it also draws a lot of inspiration (and code) from the Model & Collection patterns of Backbone.js.
I owe a lot of thanks to Taylor for writing Eloquent, he has been really helpful with any questions I've had in putting this together.
I owe a lot of thanks to Taylor for writing Eloquent, he has been really helpful with any questions I've had in putting this together.