How to do composite with gm node.js?

Question

How to do \'gm composite -gravity center change_image_url base_image_url\' with GM Node.js?

How to call gm().command() & gm().in() or <

Answer 1

Why does nobody use composite command? (https://github.com/aheckmann/gm)

var gm = require('gm');
var bgImage = 'bg.jpg',
    frontImage = 'front.jpg',
    resultImage = 'result.jpg',
    xy = '+100+150';

gm(bgImage)
  .composite(frontImage)
  .geometry(xy)
  .write(resultImage, function (err) {
    if (!err) console.log('All done');
  });

UPDATE Oh, I watched history of source of this method. It becomes available only on 2014