Example of lazy promises ( https://github.com/nathan7/lazy-promise )

lazy.js

var Q = require('q'),
    LazyPromise = require('lazy-promise');

function async(name) {
    console.log('start async: ' + name);
    var deferred = Q.defer();

    // Resolve the promise in the next turn of the event loop
    process.nextTick(function () {
        console.log('finish async: ' + name);
        deferred.resolve();
    });

    return deferred.promise;
}

// =========================================== //

console.log('= create promises =');

var promise1 = async('promise1');
console.log('got promise1');

var promise2 = new LazyPromise(function (resolve, reject) {
    async('promise2').then(resolve, reject);
});
console.log('got promise2');

// =========================================== //

console.log('= adding resolvage handlers =');

promise1.then(function () {
    console.log('resolved promise1');
});

promise2.then(function () {
    console.log('resolved promise2');
});