Enabling Couchbase N1QL engine with node.js

I'm trying to run some N1QL queries using couchbase npm package. Here's the steps I took before running the code:

1. Installed and executed Couchbase on OSX


2. Navigated to :8091 and set up the credentials as well as the beer-sample bucket


3. Downloaded the N1QL DP4 to a folder Enabled cbq-engine like so: ./cbq-engine -datastore=http://localhost:8091


4. Created a primary index as per the documentation

At this point I have localhost:8091 (primary Couchbase cluster) and localhost:8093 (DP4 engine) both live.

Here's the code I'm using from the node.js client to try to run a simple N1QL query:

var colors = require('colors'); // for console.log
var couchbase = require('couchbase');
var N1qlQuery = require('couchbase').N1qlQuery; // get query object
var myCluster = new couchbase.Cluster('couchbase://localhost:8091'); // connect to live local cluster
var myBucket = myCluster.openBucket(); // open bucket
myBucket.enableN1ql(['http://localhost:8093/']); // enable n1ql as per documentation (http://ift.tt/1yMdQW0) - I also tried :8091, same result
var query = N1qlQuery.fromString('SELECT * FROM `beer-sample` LIMIT 10');

setTimeout(function() {
  myBucket.query(query, function(err, res) {
    if (err) {
      console.log('query failed'.red, err);
      return;
    }
    console.log('success!', res);
  });
}, 2000); // just in case connecting takes a second or something?

Here's the result:

query failed { [Error: failed to connect to bucket] code: 24 }

I've tried seemingly everything and I can't find any documentation to troubleshoot this. What's going on?