Category Archives: Education

Biggest Challenges Before Joining a Coding Bootcamp

Hack Reactor students share their experiences


Perception about what being a software engineer means is probably one of the biggest challenges to overcome before joining a coding bootcamp. For decades, software engineers were perceived as scientists that require extensive education and dedication to the field. They would work on huge mainframes, programmed using punch cards and had to read whole programming language manuals before writing their first lines of code.

The world has changed since then. We have faster and cheaper computers and better developer tools, including high-level and very expressive languages like JavaScript/Node.js. For people thinking about coding bootcamp, these are all things to consider.

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You Dropped 150k on a Fucking Education?

" dropped 150K on a fucking education you could have gotten for a dollar-fifty in late charges at the public library"

Choosing a Full Time Programming Course as a Career Change

For those who aren’t familiar with the context of this quote here is a meme. The meaning is simple: why spend in the magnitude of $150,000 on professional knowledge that is available virtually for free thanks to the Internet?

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Cisco, Node.js and other musings

Thoughts about Introduction to Node.js training that I taught this week at Cisco in San Jose, CA

The hands-on Introduction to Node.js training consisted of two days and started badly: I was late driving from Oakland to San Jose through traffic, and security personnel in the lobby took extra 15 minutes to clear and escort me to the classroom. Nevertheless, attendees quickly plunged into installing Node.js, Node Package Manager and MongoDB using hard copies of Rapid Prototyping with JS: Agile JavaScript Development that I brought with me.

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Intro to Express.js: Parameters, Error Handling and Other Middleware

Note: This text is a part of Express.js Guide: The Comprehensive Book on Express.js.

Express.js is one of the most popular and mature Node.js frameworks. You can read more about in Intro to Express.js series on

To learn how to create an application from scratch please refer to the earlier post.

Request Handlers

Express.js is a node.js framework that among other things provides a way to organize routes. Each route is defined via a method call on an application object with a URL patter as a first parameter (RegExp is also supported), for example:

app.get('api/v1/stories/', function(res, req){

or, for a POST method:'/api/v1/stories'function(req,res){

It’s needless to say that DELETE and PUT methods are supported as well.
The callbacks that we pass to get() or post() methods are called request handlers, because they take requests (req), process them and write to response (res) objects. For example:

app.get('/about', function(req,res){
  res.send('About Us: ...');

We can have multiple request handlers, hence the name middleware. They accept a third parameter next calling which (next()) will switch the execution flow to the next handler:

app.get('/api/v1/stories/:id', function(req,res, next) {
  //do authorization
  //if not authorized or there is an error 
  // return next(error);
  //if authorized and no errors
  return next();
}), function(req,res, next) {
  //extract id and fetch the object from the database
  //assuming no errors, save story in the request object
  req.story = story;
  return next();
}), function(req,res) {
  //output the result of the database search

ID of a story in URL patter is a query string parameter which we need for finding a matching items in the database.

Parameters Middleware

Parameters are values passed in a query string of a URL of the request. If we didn’t have Express.js or similar library, and had to use just the core Node.js modules, we’d had to extract parameters from HTTP.request object via some require('querystring').parse(url) or require('url').parse(url, true) functions trickery.

Thanks to Connect framework and people at VisionMedia, Express.js already has support for parameters, error handling and many other important features in the form of middlewares. This is how we can plug param middleware in our app:

app.param('id', function(req,res, next, id){
  //do something with id
  //store id or other info in req object
  //call next when done

  //param middleware will be execute before and
  //we expect req object already have needed info
  //output something

For example:

app.param('id', function(req,res, next, id){
  req.db.get('stories').findOne({_id:id}, function (e, story){
    if (e) return next(e);
    if (!story) return next(new Error('Nothing is found'));
    req.story = story;


Or we can use multiple request handlers but the concept remains the same: we can expect to have req.story object or an error thrown prior to the execution of this code so we abstract common code/logic of getting parameters and their respective objects:

app.get('/api/v1/stories/:id', function(req,res, next) {
  //do authorization
  //we have an object in req.story so no work is needed here
  function(req,res) {
  //output the result of the database search

Authorization and input sanitation are also good candidates for residing in the middlewares.

Function param() is especially cool because we can combine different keys, e.g.:


Error Handling

Error handling is typically used across the whole application, therefore it’s best to implement it as a middleware. It has the same parameters plus one more, error:

app.use(function(err, req, res, next) {
  //do logging and user-friendly error message display

In fact, the response can be anything:

JSON string

app.use(function(err, req, res, next) {
  //do logging and user-friendly error message display
  res.send(500, {status:500, message: 'internal error', type:'internal'});

Text message

app.use(function(err, req, res, next) {
  //do logging and user-friendly error message display
  res.send(500, 'internal server error');

Error page

app.use(function(err, req, res, next) {
  //do logging and user-friendly error message display
  //assuming that template engine is plugged in

Redirect to error page

app.use(function(err, req, res, next) {
  //do logging and user-friendly error message display

Error HTTP response status (401, 400, 500, etc.)

app.use(function(err, req, res, next) {
  //do logging and user-friendly error message display

By the way, logging is also should be abstracted in a middleware!

To trigger an error from within your request handlers and middleware you can just call:



next(new Error('Something went wrong :-(');

You can also have multiple error handlers, and use named instead of anonymous functions as its shows in Express.js Error handling guide.

Other Middleware

In addition to extracting parameters, it can be used for many things, like authorization, error handling, sessions, output, and others.

res.json() is one of them. It conveniently outputs JavaScript/Node.js object as a JSON. For example:

app.get('/api/v1/stories/:id', function(req,res){

is equivalent to (if req.story is an Array and Object):

app.get('/api/v1/stories/:id', function(req,res){


    'Content-Type': 'application/json'


Middleware is flexible. You can use anonymous or named functions, but the best thing is to abstract request handlers into external modules based on the functionality:

var stories = require.('./routes/stories');
var elements = require.('./routes/elements');
var users = require.('./routes/users');
app.get('/stories/:storyId/elements/:elementId', elements.find);


module.exports.find = function(req,res, next) {


module.exports.find = function(req,res,next){


module.exports.update = function(req,res,next){

You can use some functional programming tricks, like this:

function requiredParamHandler(param){
  //do something with a param, e.g., check that it's present in a query string
  return function (req,res, next) {
    //use param, e.g., if token is valid proceed with next();

app.get('/api/v1/stories/:id', requiredParamHandler('token'),;

var story  = {
  show: function (req, res, next) {
    //do some logic, e.g., restrict fields to output
    return res.send();

As you can see middleware is a powerful concept for keeping code organized. The best practice is to keep router lean and thin by moving all the logic into corresponding external modules/files. This way important server configuration parameters will be neatly in one place, right there when you need them! :-)

Rapid Prototyping with JS Update v0.4

Rapid Prototyping with JS: Agile JavaScript Developement

Link to the new copy of Rapid Prototyping with JS at

Rapid Prototyping with JS: Agile JavaScript Developement

Rapid Prototyping with JS: Agile JavaScript Developement


Here is a list of the update for Rapid Prototyping with JS v0.4:

  • Brand new chapter: Intro to Backbone.js
  • Re-structured table of contents (chapters and parts)
  • Extended list of resources for further reading
  • Fixed code formatting and highlighting
  • Fixed grammar, style and typos mistakes
  • Brand new book cover optimized for ebook format
  • Reduced size of ebook (faster download)
  • Inspirational quotes in each chapter
  • Updated “Basics” chapter
  • New headline “Agile JavaScript Development”
  • Extended list of ways to reach us (Twitter, Facebook, Storify, etc.)

LeanPub Updates

LeanPub changed their purchasing. Now it’s even better for readers. Anybody can “return” the book they didn’t like within 45 days and get a full refund. Word return is in double quotes because all content is Digital Right Management (DRM) free. Does it mean that somebody can buy and download a book, get their money back, but keep the copy? Yes, but they will get bad karma for that! And not like a bad karma on Hacker News but a real bad karma. Everybody else deservers authors and publishers trust and respect.


Why Backbone.js? Because a lot of people expressed desire to use it but being a framework Backbone has a learning curve. Not a steep one like Rails but still it takes time to master and learn Backbone. The new chapter “Intro to Backbone.js” will show readers how to:

  • Create Backbone architecture from scratch
  • Construct proper architecture with Routes
  • Use Collections
  • Apply Templates in Subviews
  • Split code into multiple JS files
  • Organize code into modules with AMD and Require.js
  • Optimize code for production with r.js library

Write and follow @RPJSbook.

Test-Driven Development in Node.js With Mocha

Who needs Test-Driven Development?

Imagine that you need to implement a complex feature on top of an existing interface, e.g., a ‘like’ button on a comment. Without tests you’ll have to manually create a user, log in, create a post, create a different user, log in with a different user and like the post. Tiresome? What if you’ll need to do it 10 or 20 times to find and fix some nasty bug? What if your feature breaks existing functionality, but you notice it 6 months after the release because there was no test!

Mocha: simple, flexible, fun

Mocha: simple, flexible, fun

Don’t waste time writing tests for throwaway scripts, but please adapt the habit of Test-Driven Development for the main code base. With a little time spent in the beginning, you and your team will save time later and have confidence when rolling out new releases. Test Driven Development is a really really really good thing.

Quick Start Guide

Follow this quick guide to set up your Test-Driven Development process in Node.js with Mocha.

Install Mocha globally by executing this command:

$ sudo npm install -g mocha

We’ll also use two libraries, Superagent and expect.js by LeanBoost. To install them fire up npm commands in your project folder like this:

$ npm install superagent
$ npm install expect.js   

Open a new file with .js extension and type:

var request = require('superagent');
var expect = require('expect.js');

So far we’ve included two libraries. The structure of the test suite going to look like this:

describe('Suite one', function(){
describe('Suite two', function(){

Inside of this closure we can write request to our server which should be running at localhost:8080:

it (function(done){'localhost:8080').end(function(res){
    //TODO check that response is okay

Expect will give us handy functions to check any condition we can think of:


Lastly, we need to add done() call to notify Mocha that asynchronous test has finished its work. And the full code of our first test looks like this:

var request = require('superagent');
var expect = require('expect.js');
describe('Suite one', function(){
 it (function(done){'localhost:8080').end(function(res){

If we want to get fancy, we can add before and beforeEach hooks which will, according to their names, execute once before the test (or suite) or each time before the test (or suite):

  //TODO seed the database
describe('suite one ',function(){
    //todo log in test user
  it('test one', function(done){

Note that before and beforeEach can be placed inside or outside of describe construction.

To run our test simply execute:

$ mocha test.js

To use different report type:

$ mocha test.js -R list
$ mocha test.js -R spec

Cheat Sheets for Web Development

Cheat sheets are great ways to organize frequently used information and keep it handy. I used cheat sheets for learning and memorizing during my crams at school, and use them now for reference.

Cheat sheet for Web Development

Cheat sheet for Web Development

Web development usually involves a large number of languages each with its own syntax, keywords, special sauce and magic tricks.
Here is a collection of web development cheat sheets, in no particular order, which I’ve amassed by browsing the Internet over many years of web development. They cover the following topics:

  • jQuery
  • CSS3
  • Git
  • Heroku
  • HTML5
  • Linux Command Line
  • Mod reWrite
  • CoffeeScript
  • JavaScript
  • CSS2
  • JavaScript DOM
  • Mac Glyphs
  • Node.js
  • PHP
  • RGB Hex
  • Sublime Text 2
  • SEO
  • WordPress

Get zip archive at

Full list of the files:

CSS Help Sheet outlined.pdf
CSS3 Help Sheet outlined.pdf
HTML Help Sheet 02.pdf
Node Help Sheet.pdf
PHP Help Sheet 01.pdf

Wintersmith — Node.js static site generator

This past weekend was a very productive one for me, because I’ve started to work on and released my book’s one-page website — I’ve used Wintersmith to learn something new and to ship fast. Wintersmith is a Node.js static site generator. It greatly impressed me with flexibility and ease of development. In addition I could stick to my favorite tools such as Markdown, Jade and Underscore.

Wintersmith is a Node.js static site generator

Why Static Site Generators

Here is a good article on why using a static site generator is a good idea in general, An Introduction to Static Site Generators. It basically boils down to a few main things:


You can use template engine such as Jade. Jade uses whitespaces to structure nested elements and its syntax is similar to Ruby on Rail’s Haml markup.


I’ve copied markdown text from my book’s Introduction chapter and used it without any modifications. Wintersmith comes with marked parser by default. More on why Markdown is great in my old post, Markdown Goodness.

Simple Deployment

Everything is HTML, CSS and JavaScript so you just upload the files with FTP client, e.g., Transmit by Panic or Cyberduck.

Basic Hosting

Due to the fact that any static web server will work well, there is no need for Heroku or Nodejitsu PaaS solutions, or even PHP/MySQL hosting.


There are no database calls, no server-side API calls, no CPU/RAM overhead.


Wintersmith allows for different plugins for contents and templates and you can even write you own plugin.

Getting Started with Wintersmith

There is a quick getting started guide on

To install Wintersmith globally, run NPM with -g and sudo:

$ sudo npm install wintersmith -g

Then run to use default blog template:

$ wintersmith new <path>

or for empty site:

$ wintersmith new <path> -template basic

or use a shortcut:

$ wintersmith new <path> -T basic

Similar to Ruby on Rails scaffolding Wintersmith will generate a basic skeleton with contents and templates folders. To preview a website, run these commands:

$ cd <path>
$ wintersmith preview
$ open http://localhost:8080

Most of the changes will be updates automatically in the preview mode except for the config.json file.

Images, CSS, JavaScript and other files go into contents folder.
Wintersmith generator has the following logic:

  1. looks for *.md files in contents folder,
  2. reads metadata such as template name,
  3. processes *.jade templates per metadate in *.md files.

When you’re done with your static site, just run:

$ wintersmith build

Other Static Site Generators

Here are some of the other Node.js static site generators:

More detailed overview of these static site generators is available in the post, Node Based Static Site Generators.

For other languages and frameworks like Rails and PHP take a look at Static Site Generators by GitHub Watcher Count and the “mother of all site generator lists”.

Rapid Prototyping with JS is out!

The Book is on LeanPub

Rapid Prototyping with JS is a hands-on book which introduces you to rapid software prototyping using the latest cutting-edge web and mobile technologies including NodeJS, MongoDB, BackboneJS, Twitter Bootstrap, LESS, jQuery,, Heroku and others.

The book has 84 pages (in PDF format) or 13,616 words to be precise, step-by-step set-up, best practice advices, web development overview, 11 code examples (also available ready-to-go in GitHub repository azat-co/rpjs), flexible pricing ($9.99–19.99).

Order your copy of Rapid Prototyping with JS at LeanPub:

Rapid Prototyping with JS

Rapid Prototyping with JS: Learn how to build web and mobile apps using JavaScript and Node.js

LeanPub platform allows readers to receive infinite future updates (current version of the book is 0.3) and read the book in the most popular digital formats: PDF, ePub/iPad, MOBI/Kindle. The PDF version has footnote links which make it suitable for printing.

Download a free sample at

What Readers Say

Rapid Prototyping with JS is being successfully used at StartupMonthly as a training manual. Here are some of our trainees’ testimonials:

“Thanks a lot to all and special thanks to Azat and Yuri. I enjoyed it a lot and felt motivated to work hard to know these technologies.” — Shelly Arora

“Thanks for putting this workshop together this weekend… what we did with Bootstrap + Parse was really quick & awesome.” — Mariya Yao

“Thanks Yuri and all of you folks. It was a great session – very educative, and it certainly helped me brush up on my Javascript skills. Look forward to seeing/working with you in the future.” — Sam Sur

Who This Book is For

The book is designed for advanced-beginner and intermediate level web and mobile developers: somebody who has just started programming and somebody who is an expert in other languages like Ruby on Rails, PHP, and Java and wants to learn JavaScript and Node.js.

Rapid Prototyping with JS, as you can tell from the name, is about taking your idea to a functional prototype in the form of a web or a mobile application as fast as possible. This thinking adheres to the Lean Startup methodology. Therefore, this book would be more valuable to startup founders, but big companies’ employees might also find it useful, especially if they plan to add new skills to their resume.


Mac OS X or UNIX/Linux systems are highly recommended for this book’s examples and for web development in general, although it’s still possible to hack your way on a Windows-based system.




  1. Who This Book is For
  2. Prerequisite
  3. What to Expect
  4. Notation
  5. Web Basics: Hyper Text Markup Language, Cascading Style Sheets, JavaScript
  6. Agile Methodologies: Scrum, Test-Driven Development, Continuous Deployment, Paired Programming
  7. Node.js
  8. NoSQL and MongoDB
  9. Cloud Computing
  10. HTTP Requests and Responses
  11. RESTful API

Getting Started

  1. Development Folder
  2. Browsers
  3. IDEs and Text Editors
  4. Version Control Systems
  5. Local HTTP Servers
  6. Database: MongoDB
  7. Other Components: NodeJS, jQuery, LESS
  8. SSH Keys
  9. GitHub
  10. Windows Azure
  11. Heroku
  12. Cloud9

Building Front-End Application

  1. JSON
  2. AJAX
  3. Cross-Domain Calls
  4. jQuery
  5. Twitter Bootstrap
  6. LESS
  7. BackboneJS
  8. Example of using Twitter REST API and jQuery
  10. Message Board with
  11. Message Board with REST API and jQuery version
  12. Pushing to GitHub
  13. Deployment to Windows Azure
  14. Deployment to Heroku
  15. Message Board with JavaScript SDK and BackboneJS version
  16. Deploying Message Board to PaaS
  17. Enhancing Message Board
  18. Building Back-End Application

Building “Hello World” in NodeJS

  1. NodeJS Core Modules
  2. Node Package Manager
  3. Deploying “Hello World” to PaaS
  4. Deploying to Windows Azure
  5. Deploying to Heroku
  6. Message Board: Run-Time Memory version
  7. Test Case for Message Board
  8. MongoDB Shell
  9. MongoDB Native Driver
  10. MongoDB on Heroku: MongoHQ MongoHQ URL
  11. BSON
  12. Message Board: MongoDB version

Putting it All Together

  1. Different Domain Deployment
  2. Changing Endpoints
  3. Message Board Application
  4. Deployment
  5. Same Domain Deployment

Further Reading

About the Author

Order your copy of Rapid Prototyping with JS at LeanPub: