Keybase.io Login w/NodeJS using Request, Crypto, and Scrypt

keybaseLogin.js

// Get salt: https://keybase.io/docs/api/1.0/call/getsalt
// Login: https://keybase.io/docs/api/1.0/call/login
var request = require('request');
var scrypt = require('scrypt');
var crypto = require('crypto');
var username = "myUsername";
var password = "myPassword";
request('https://keybase.io/_/api/1.0/getsalt.json?email_or_username=' + username, function (error, body, results) {
  if(error) {
    console.log(error);
    return;
  }
  results = JSON.parse(results);
  if(results.status.code === 0) {
    var loginSession = results.login_session;
    var csrfToken = results.csrf_token;
    var salt = results.salt;

    scrypt.kdf.config.saltEncoding = "ascii";
    scrypt.kdf.config.keyEncoding = "ascii";

    var bytes = [];
    for(var i=0; i< salt.length-1; i+=2){
        bytes.push(parseInt(salt.substr(i, 2), 16));
    }
    var binarySalt = String.fromCharCode.apply(String, bytes);

    scrypt.kdf(password, {N: Math.pow(2,15), r:8, p:1}, 224, binarySalt, function(err, result){
      
      var hash = crypto.createHmac('sha512', result.hash.slice(192, 224));
      hash.update(new Buffer(loginSession, 'base64'));
      var hashedData = hash.digest('hex');
      
      request.post('https://keybase.io/_/api/1.0/login.json', {form: {
        csrf_token: csrfToken,
        login_session: loginSession,
        email_or_username: username,
        hmac_pwh: hashedData
      }}, function (error, body, response) {
        if(error) {
          console.log(error);
          return;
        }
        console.log(response);
      });
    });
  }
});