JavaScript Tech Interview Exercise 9: Event Delegation in a Pomodoro App

You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring the best talent. I have also been in the candidate position, interviewing ... more

JavaScript Tech Interview Exercise 8: Video Player

You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring the best talent. I have also been in the candidate position, interviewing ... more

JavaScript Tech Interview Exercise 7: Painting on an HTML5 Canvas

You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring the best talent. I have also been in the candidate position, interviewing ... more

Binary Trees, Recursion, Tail Call Optimization in JavaScript

You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring the best talent. I have also been in the candidate position, interviewing ... more

JavaScript Theory Quiz – Crack the ES6 Interview

You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring the best talent. I have also been in the candidate position, interviewing ... more

JavaScript Tech Interview Exercise 5: Connect-4 Solver in ES6

This interview question is also available as a video on my Youtube channel. You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring ... more

Strings and Template Literals in ES6

It is time to have a look at string manipulation and template literals. There has been a shift in the trends of web development in the last ten years that moves the responsibility of rendering from the server side to the client side. Therefore, the HTML ... more

Ten JavaScript Theory Questions – The ES6 Quiz

There are countless questions your interviewers may ask when it comes to how JavaScript works. The idea behind asking these questions is to assess whether you have recent experience in writing JavaScript code. Some more clueless interviewers tend to ... more

Regular Expressions in PHP

This blog has been about JavaScript so far. However, with the topic of regular expressions, we are diving in more deep waters. As a refresher, some other languages will also surface on our horizon. In this post, we will get started with writing and testing ... more

JavaScript Tech Interview Exercise 2: Binary Gap Exercise in Codility

Exercise: Suppose a positive integer N is given. Determine the binary representation of N , and find the longest subsequence of form 10*1 in this representation, where 0* stands for any number of zeros in the sequence. Examples: 11 , 101 , 1001 , 10001 ... more

Regular Expressions in JavaScript

It is very easy to experiment with JavaScript regular expressions, as JavaScript is accessible in all browsers. I will use the Chrome Developer Tools to execute regular expressions. The > symbol denotes an input. The return value and console logs ... more

JavaScript Tech Interview Exercise 1 – Writing an Array Extension

You might not know about me that I have conducted tech interviews with over 500 software developers from more than twenty countries with the objective of identifying and hiring the best talent. I have also been in the candidate position, interviewing ... more

An Introduction to Regular Expressions – Why Most People Can’t Read Regex

I still remember my doomed encounters with regular expressions back when I tried to learn them. In fact, I took pride in not using regular expressions. I always found a long workaround, a code snippet that was quite long. I projected and blamed my own ... more

ES6 Promises – Quick Start Guide

Promises represent the eventual result of an asynchronous operation. They give us a way to handle asynchronous processing in a more synchronous fashion. A promise represents a value we can handle in the future, with the following guarantees: promises ... more

What’s new in React 16.0?

Not too long ago, React made a jump from version 0.14 to 15.0. Following this major jump, the first major version update has arrived. Let’s examine what surprises React 16.0 holds for us. Gentlemen, Start Your Engines! Facebook claims they have completely ... more

Container Components and Stateless Functional Components in React

In the article Building a Chat Component in React and ES6, we learned a way to create React components: import React from 'react'; class SimpleComponent extends React.Component { render() { return ( <div>{this.props.message}</div> ); } } ... more

Creating Controlled Components in React

In this short article, you will get a chance to learn what controlled components are and why they are beneficial. Suppose a component has an input field with a value depending on the state of the component. The default value of the component is placed ... more

ES6 Proxies in Practice

A proxy is an object that wraps an object or a function and monitors access to the wrapped item, a.k.a. the target . We use proxies for the intention of blocking direct access to the target function or object. The proxy object has some traps , handling ... more

How to Shatter Magic Numbers in Software Testing

Bread is made by mixing ingredients of more or less fixed proportions. There is a tolerance around these proportions defined by the quality standards. This level of tolerance ensures that the quality of the mix stays the same regardless of the environmental ... more

Video Tutorial – ES6 Arrow Functions with 3 Exercises

In this article, I will introduce my new Youtube channel with two videos. Both videos are from ES6 in Practice. By watching these short videos, you can learn about Arrow Functions, and you can also put theory into practice by solving three exercises. ... more

Understanding the Console API in JavaScript – 7 Tips for Smoother Debugging

Many JavaScript developers only use the console.log statement for the purpose of finding out more about how their application works. In this article, you will learn that the console API contains many powerful methods that will significantly improve your ... more

Use ESLint Like a Pro with ES6 and React

In this article, we will extend our application setup with linting. If you have not read my article on setting up a JavaScript application with React, I highly recommend reading it first. Setting Up ESLint ESLint helps us catch mistakes by enforcing ... more

The Reflect API of ES6

Reflection in a programming language is the act of inspecting, dynamically calling, and modifying classes, objects, properties, and methods. In other words, reflection is the ability of the programming language to reflect on the structure of the code. ... more

ES6 Symbols and its Use Cases

This article is a section from the course ES6 in Practice. I created this course during the last couple of months, because there is an evident need for a resource that helps JavaScript developers put theory into practice. This course won’t waste your ... more

Building a chat component in React and ES6

This is the third part of the React-Redux series. In the first part, we introduced React and Redux. Although there was no code in the article, clarifying the concepts is still important. In the second part, we set up the development environment with ... more

ES6 Iterators and Generators – 6 exercises and solutions

This article is a section from the workbook of ES6 in Practice. I created this course during the last couple of months, because there is an evident need for a resource that helps JavaScript developers put theory into practice. This course won’t waste ... more

ES6 Iterators and Generators in Practice

This article is a section from the course ES6 in Practice. I created this course during the last couple of months, because there is an evident need for a resource that helps JavaScript developers put theory into practice. This course won’t waste your ... more

Step by Step Environment Setup of the React Developer – No Legacy, 2016 Standards

Written on October 25th, 2016. No updates have been applied to the step by step application setup. This paragraph will always reflect the actuality of the article. I recently started reviewing React applications of many software developers, who just ... more

New Tutorial Series: Building a Web-Application using React and Redux

This is the first article in the series on developing maintainable Web-Applications with React and Redux. The goal of this series is to give you a fully up to date view on how to create a web application, sticking to the highest standards, and using ... more

The Developer’s Edge – Double Your Career Speed with Soft-Skills

In last week’s article, I presented the new path to you. I also announced a concluding article about soft-skill, leadership, and career topics. These topics will be continued on my new website, devcareermastery.com. Dev Career Mastery Many people are ... more