I use a combination of promises for async and monadic results for sync, which enables me to write consistent code with "enforced" error-handling.

'use strict';

const defer = require('promise-defer');
const Result = require('result-js');
require('verror');


const fnAsync = function() {
    const d = defer();
    setTimeout(() => {
        d.reject(new VError({
            name: 'DummyError',
            info: {
                code: 12345,
            },
        }, 'This is an async %s error!', 'dummy'));
    }, 1000);

    return d.promise;
};

const fnSync = function() {
    return Result.fromError(new VError({
        name: 'DummyError',
        info: {
            code: 12345,
        },
    }, 'This is a sync %s error!', 'dummy'));
};

fnAsync().then(result => {}, error => {});
fnSync().then(result => {}, error => {});

I use a combination of async/ await and promises! :)