I had an interesting bug in my React application. It happened that the problem was in the fact that I was using forEach instead of for.

The bug that I was encounter was

Recently we had an interesting task at work. The user makes a selection of items and clicks a button. Then for every selected item we have to make a request to our API. The thing is that the user may click as many items as he/she wants. In order to speed up the process we decided to handle four requests in parallel and once some of them is finished we pull the next one. If you ask why exactly four requests in parallel read this paper.

I like reading code of other developers. It’s a nice way to learn patterns, techniques and small tricks. Recently I found something about Array.prototype.length which caught my attention.

I love using functions like map, filter or reduce. They are an important part of my arsenal and I simply can’t stop using them. Today I had to solve an interesting problem and I ended up using reduce.

Readers would be pleased to know that I have teamed up with Packt Publishing to organize a Giveaway of a new book written by me - Node.js Blueprints. And three lucky winners stand a chance to win 3 e-copies of this book. Keep reading to find out how you can be one of the Lucky Winners.

Hi guys, you would be pleased to know that I have teamed up with Packt Publishing to organize a Giveaway of the new book - Getting Started with Grunt: The JavaScript Task Runner. And three lucky winners stand a chance to win 3 digital copies of this book. Keep reading to find out how you can be one of the Lucky Winners.

I was surprised by the good feedback for JavaScript template engine in just 20 lines and decided to blog for another small utility function which I'm using often. While we are talking about JavaScript in the browser, most of the operations are asynchronous. We are dealing with callbacks all the time and sometimes we end up with awesome callback hell.

As javascript developers we all have to write a lot of for loops. Before a couple of months I saw an alternative syntax, which I really liked. It saves some time and it looks much nicer. However, one of my colleagues reported that this fancy syntax is not working as it should.

I'm currently working on a JavaScript application which is using the facebook API. There are some things which I need to pass from one page to the other. So, I decided to use cookies. The storing works like a charm, but the deleting doesn't. I needed one hour to find the exact problem.

In my company, we have a lot of WordPress sites. Some of them require contact form with captcha field. The short way for solving such task is to use a plugin. However, as you may guess, the add-ons are available for everyone, which means that they could be easily explored and probably hacked. That's why I suggested a simple, custom script, which is developed by us.

By my opinion one of the biggest problems in programming are dependencies. If you want to have a good well written application you should avoid dependencies between your modules/classes. There is a design pattern which could help and it's called Dependency Injection (DI). It allows you to inject objects into a class, instead of creating them there.

I'm not exactly a performance perfectionist, but currently I'm working on a tool which will be used in a large system. It will deliver texts to a multi-language environment and there will be several sites/apps which will performe big amount of request to it. It is the right moment for me to choose how to speed up my code and the work of the tool overall.

As you probably know there is no such kind of option. We should deal with a little AS3 code.

Simple and easy solution.

There are some features in Flash that we can't work without. Tween classes are among the most used ones. They give you ability to animate objects without using the timeline, to change the animation fast and easy. The idea of these classes is very simple. That's why I think that it is a good idea to have your own tween manager that you can modify to fit into your needs.