So now to get really deep/meta, you'll want to combine with promisify:

    var isTrue = require('callbaxx').isTrue;
    var promisify = require('promisify');
    var promIsTrue = promisify(isTrue);
    
    promIsTrue(true)
      .then(function (res) {
        console.log(res)
      });
      .catch(function (err) {
        console.log(err)
      });