Many moons ago, I was writing a lot of Flash applications. One thing was typical, and that was a progress indication of something that we were downloading. The loaded bytes of the Flash file (.swf) itself and later of some other resource the application needs. Once I started writing everything in JavaScript, this feature disappeared. In this post, we'll see how to implement it with vanilla JavaScript.

It's unsurprising that we all use Express.js when we need a web server. In this article, I'll show you how I built a source viewer. It's distributed as a npm package view-source and it could render the content of a directory in a nice tree-view style.

I did roughly 50 talks over the years, and for almost all of them, I used Reveal.js. I like it because it's HTML-based. I have complete control of everything and can easily publish the slides online. However, one thing bugs me every single time - the size of my content. I want to use all the available space. This becomes very important when I'm showing code to people. That's why I wrote SimPre. It's a 10KB HTML presentation framework that properly scales and positions my content.

The first post in this blog was published on 25th of August 2008. This place was always living on a shared PHP/MySQL hosting. It was driven by a custom made PHP CMS for over 10 years. It is time to move forward and follow my actual language of choice - JavaScript. I spent some time recently migrating it to Zeit and this article is showing my process.

I had some time during the weekend and decided to work on my slides for an event at the end of the month. I reached the part where I have to do a live coding session and I was wondering what tool to use. At the end I created my own called Demoit. This is a short article explaining how it works.

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.

(If you are lazy jump to this section to learn what is this article all about.)

Remember The Island movie from 2005. I watched it again these days and I realized that the old sci-fi titles start with something really interesting. It is funny how they create a world of flying vehicles and say something like "The year is 2019 …". Well, we are 2018 and the public transport is still on the ground. We still can't clone people (I hope so) or travel in a giant spaceship which looks like a fully-functional city.

Sometimes when you learn something new you get really excited. Excited to that level so you want to teach it to someone. That is the case with the concept which I found a couple of months ago. It is an implementation of the command pattern using generators. Or the well known saga used in the redux-saga library. In this article we will see how the idea makes our asynchronous code simpler and easy to read. We will also implement it ourself using generators.

Recently I started questioning the state management in React applications. I’ve made some really interesting conclusions and in this article I’ll show you that what we call a state management may not be exactly about managing state.

One of my favorite conferences Bulgaria Web Summit 2017 is just around the corner. I’m happy to attend again. The organizer prepared a good set of speakers and the event is two days this year.

If you are front-end developer dealing with single page applications you probably know that JavaScript ecosystem is not perfect at all. A few things may go wrong and break your build. In this article I’ll go through those features. Features which are, by my humble opinion, problematic.

You have no idea how fun is to transpiler JavaScript. I’m digging into that last few weeks and there is a step where I have to transform an AST into valid code. There is one tree node which I really like - sequence expression.

Well, I kind of lied in the title of this article. Of course that it is the end of the function. Once we call return everything else after that is simply not executed. Ops … I did it again, I kind of lied again.

The new ES6 specification of JavaScript simply works better for me. It helps expressing my ideas in a shorter and cleaner way. So, I want to write ES6 everywhere. Even while I’m testing my applications.

Before a couple of months my first book Node.js Blueprints was published by Packt. There are a couple of reviews in Amazon about chapter two. It’s about Express. One of the most popular frameworks in the Node.js ecosystem. The book mentions version 3.0 but the truth is that the code samples are for version 4.0. I feel that I still have to point out the differences and mark these parts of the chapter that are not valid for the newest version of the library.

Node.js is one of those new technologies, which are attracting more and more developers every day. Mainly, because it's JavaScript driven, a lot of people are interested working with it. In this tutorial, I'll show you how to use AbsurdJS together with Express. Express is one of the popular Node.js frameworks. However, the other instrument is really fresh one and I hope that you will find it useful.

Okey, I normally don't write such articles. The things that I am writing about are technical stuff, concepts, experiments related to my job. However, this time will be a little bit different. I had a chance to speak at Codefront conference. And because it was so awesome I decided to share my experience.

There are only two weeks left before the international front-end conference in Linz - Codefront.io. It's organized by the guys from WebBox and it's scheduled for 10th of May. You still have a chance to buy a ticket and listen interesting talks about our lovely Web.

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.

While I worked on AbsurdJS I needed a function which accepts numerous objects and combines their properties. I.e. something like the _.extend method of UnderscoreJS. What I did is actually to use one more dependency just because of such method. John-David Dalton nicely pointed out my mistake and added a simple function which solved the problem. I change it a bit and now it acts as UnderscoreJS's version.

I just read this very interesting article published on know.cujojs.com. It's about aspect oriented programming. At the beginning I thought "Oh, that's kinda cool", but when I start thinking about how I'll use it in practice I notice something bad. The blog post itself is well written and informative, but doesn't include any cons of the used technique.

I really like SASS and I use it a lot in my daily job. There are tons of useful features. However there are some things which I want to do, but I can't. There are limitation in the syntax and missing functionalities. Sharing what I found, I want to know if you meet those limitation and how you get around them.

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.

I created a simple JavaScript library for running functions in a sequence. The story behind this is published here. Today I made few interesting changes which deserve a new blog post.

While I'm working on Auxilio I end up in a sitatuation where I have to call few javascript functions in a sequence. It's an interesting how this could be solved and I'll be happy if you share your opinion for such problem.

Everyday I'm reading or watching something which I find helpful. Normally I bookmark those things, but at the end I have dozen of folders and subfolders which I never check. So, I decided to make such blog post where I'll share valuable things in the net.

In this article I want to share my thoughts regarding responsive design. I made several talks on this subject and this post is some kind of summary. The article presents concepts like mobile first and design in the browser.

It's a little big difficult for me to write long articles. This one is maybe the longest, which I ever wrote :) It collects my experience with responsive design. I believe that the ideas described in the material are important for our work as web designer and developers. David Walsh was really kind by publishing the article on his blog. You can find it here http://davidwalsh.name/design-responsively.

Presentation's slides. All my talks at VarnaLab are available here.

The goal is to achieve a background of the text inside an inline element.

I'm going to start a new project with ExpressionEngine. So, I made a short review of the framework's capabilities. The article is available at my account in tech.pro.

A bunch of cool stuff ;-)

Some of the cool and helpful things which I found in the net.

float property is one of those CSS rules which are somehow difficult to understand. Before a couple of days I had a problem with floating divs. I solved it and decided to write an article about the solution. The article also covers some basics about floating.

Today is a day for posting videos. Another interesting conference - JSConf 2012. The videos are available here http://2012.jsconf.us/.

If you are in Varna, Bulgaria this Saturday please visit "Chernorizets Hrabar" Free University of Varna. Really interesting conference, with great speakers. More about the event, lecturers and everything else here http://varnaconf.com/.

For some time, I bring a lot of attention to the tests of everything that I'm working on. Actually Test Driven Development changed a lot my vision for programming. Dale Emery shares really interesting thoughts regarding automated testing. Checkout here. If you wonder what are the characteristics of a good test suite read this article http://arlobelshee.com/what-makes-a-good-test-suite.

Maybe one of the best explanations of the prototype in the context of JavaScript language.http://javascriptweblog.wordpress.com/2010/06/07/understanding-javascript-prototypes/

Did you ever wonder how Facebook's release management looks like. Here is an interesting article about that http://arstechnica.com/business/news/2012/04/exclusive-a-behind-the-scenes-look-at-facebook-release-engineering.ars/1

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.

In my opinion that principle is really important and stays in the fundamentals of software design._In the context of the Single Responsibility Principle (SRP) we define a responsibility to be "a reason for change." If you can think of more than one motive for changing a class, then that class has more than one responsibility. This is sometimes hard to see._Read more about this principle here.

The European JavaScript conference is really close. It's scheduled for 01 and 02 of October. I wish I could be there. I hope that the videos from the lectures will be shared online, as this happened for the last year. I strongly recommend to watch them. There are available here http://blip.tv/jsconfeu.

Facebook became one of the most popular social platforms these days. I just finished a flash based game that uses their API and decided to share my experience.

When we are talking about maps, Google is an absolute leader. Their GoogleMaps tool is free, well documented and works really good. What I didn't find directly in the documentation is how to get the exact location based on plain text. I.e. to convert an address to google.maps.LatLng object. That's why I wrote a simple function that did this job.

After a couple of days of using my script for file opening I decided to rewrite it and add more functionalities.

I'm absolutely sure that you've already met this problem. You know, these nice rounded buttons that are provided by the designer. They are really cool, but sometimes the label of the button is so long that you have to resize/scale the image. ActionScript3 provides simple way to solve this issue.

Many people will say that Flash is not SEO friendly. Actually that's not 100% true. Flash is just a tool that shows your data. Exactly the same as the HTML. In this article I'll show you how to use ActionScript3 and JavaScript together to make your flash sites SEO friendly and provide a different URL for each of your pages.

Resn - Interactive Agency

1. Moving background layer - sometimes you want to move the background layer. But by default it's locked. So just click twice on the layer and choose "OK" in the popup message. The layer will be transformed to normal layer.