I spoke at an event last week, and on the very last slide, I had a QR code that was supposed to lead people to my contacts page. Well, it didn't. I used a service for "free" QR code generation, and the link expired. So, I learned my lesson and came up with a line that generates whatever code I need right into my terminal.

Reactivity became de-factor a standard in the last couple of years. All the major frameworks have some reactivity model implemented. One of the biggest even has the name React. In this article, we'll see how to write a simple reactive UI with just a few lines of JavaScript.

I did use Sass and Less in the past, and one of my favorite features was the nesting. Not only me but the whole community was asking about that constantly over the years. The browser vendors heard that plea, and today, we have CSS nesting.

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'm not open-sourcing very often anymore, but recently I finished developing a small tool called q2m that I believe is worth sharing. It's a library designed to convert URL parameters into MongoDB queries, which I needed for my latest project, a little SaaS called Lumina CMS.

Some people say that 2023 will be the year of AI. With tools like ChatGPT and DALL·E the world is definitely changing. There are different opinions on how such instruments will affect the everyday tasks of the professionals. My two cents (for now) are that those are just tools to achieve what we want quicker and more efficiently. Who knows, someday I may call myself a "prompt engineer". For the time being, though, I'm still writing a lot of stuff alone and occasionally ask ChatGPT for help.

I hit an interesting "bug" while working on a SPA application. Clicking an anchor link that points to a fragment on the page fires the History API's popstate event. This triggers some logic on my end, which was not my intent. I fixed that with a bit of JavaScript, and I had to share the snippet.

Last year or so, I worked on a platform where I would publish video courses. The first one is on web fundamentals (in Bulgarian), and it's almost ready. You can check it out here. But this article is not about that. It's about a platform feature I built - an in-house validator to exercise the gained HTML, CSS, and JavaScript knowledge. After each lesson, I give a task to the students, and they can work on it right in the browser. The small application became an inspiration for another project - iloveweb.dev. So, I decided to share how the validation works.

I'm sure you know what Wordle is. The game got a lot of traction a couple of months ago when The New York Times bought it. I was playing it too, so I decided to create my version in my native language (Bulgarian). This is how duma.fun was born (in Bulgarian duma means word). And as usually happens with my "little" experiments, I didn't stop at just implementing the basics. I managed to translate the initial ~300 lines of code into a three months-long project. Here's why, what, and how.

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.

I'm committing to posting a report at the end of each year. A report about this blog. I did the last one five years ago when this place was eight years old.

I like to write. It's not happening often, but I do. A couple of weeks ago, I finally finished my 5th book, "50 Tips on JavaScript". I decided to use Amazon as a distributing mechanism. In this article, I'm sharing my journey. From the idea, through the writing and the publishing.

Tamo Junto is an independent animated short film by flooul animation. 2 neighbors lean on each other, turning small moments of life into great treasures. Voices by Criolo, Luciana Silveira and Emicida. Original Soundtrack By Loud+

Did you ever wondered how the call-to-action widgets work? You know, those little buttons for sharing content in the social networks. Very often they are distributed as iframes but sometimes we have to copy/paste script tags. And the instructions are "Place the following code where you want the button to appear". But if that's a script tag how it knows where to inject the button? The goal of this article is to give you an answer on this question.

A short movie for Kent C. Dodds.

A white label app is an app that we build once and "resell" it to other people/companies. Very often we are talking about applying different themes but sometimes we have to change logic too. Such changes should be as declarative as possible so they scale well. Otherwise is more of a copy/paste exercise. In this article I want to sketch out a couple of approaches for white labeling in React applications.

I'm working on a personal project and I'm using the awesome Google Cloud Platform. There are so many things that you can do. All the tools that you may need are probably there. This of course comes with a price. In this article I'll share a tip how to reduce your spendings there.

Hot topic last couple of years is state management. Especially in the front-end apps. There are lots of problems and lots of solutions. One thing thought is totally ignored in this context - the JavaScript module system. I'm very often reaching out to this approach and decided to share it here.

These days I did (again) a bunch of changes in Google tag manager. This time however was more of a refactoring exercise. So, I had to prove that the tags that were placed before the refactoring exist after the refactoring. And what we programmers do in such cases - we write tests.

Back in February last year I blog on topic Email not working after DNS change. Well, I had kinda similar situation but not exactly. This time I bought a domain from Google and wanted to use an email with it. The setup wasn't obvious for me so I decided to document the process.

The router is the backbone of your application. Trust me, that's how it is and I can prove it. One of the fundamental ideas in Web is the URL (Uniform Resource Locator). Or the way of how we very often call it - "web address". No mather what you are building there is a web address which identifies your resource. The router is the front office that accepts the request to particular URL and wires it to a logic. Logic for generating HTML or JSON response or something else. So, the router is very important part of your system.

At the end of last year I rewrote one of my favorite projects - a vanilla JS router called Navigo. I was procrastinating this work for years. Finally I did it in TypeScript and wrote 100+ unit tests along the way. This refactoring opens the door for new features and more importantly, for integrating the library into other places. Like React for example.

While I was working on Navigo an issue popped out. It was about using the library in the context of Web Dev Server where we have everything in TypeScript. And something was not ok with Navigo. The npm package wasn't exported properly and we were keep getting a does not provide an export named 'default' error. It turned out the problem is that Navigo is not exported properly as ES module (also known as ESM).

I'm recently working on two OS libraries. Both I'm unit testing with Jest. There is some logic that leads to a warning which I'm doing with console.warn. In the unit tests this is happening quite often so I want to suppress it. Also I want to verify that it happens on the right place.

At work we have a project that uses node:10-jessie image as a base for its docker container. That image has no vi inside so I wondered how to check the content of a file. Luckily kubectl has a neat command to copy files from and to a pod.

If you are building some sort of an app, Babel is probably part of your build system. It is that thing which converts our fancy code to valid, working in a browser, JavaScript. Just recently at work I had to design a solution that swaps a class based on the environment. Or in another words, we have logic that should not reach our users. The file should be available locally and on our staging environment but not in production. A tiny Babel plugin was the cheapest solution for me so I decided to share the result.

Last weekend I was helping a friend to deal with his "broken" iPhone XR. It was stuck on the Apple logo. No mather what we do the phone was just black and the apple shows up.

I did transfer MP3 files from my mac to my iPhone three times and every time I'm forgetting how it actually works. So I decided to document the process into a blog post.

Just recently I had to do changes in Google Tag Manager at work. It's interesting how I keep forgetting how everything works. So I finally decided to sit down and write an article about these things. If nothing else I will have a good memory snapshot to remind me what is what.

JavaScript is your behavior layer; the way to add interactivity to your sites, to provide a slick and delightful user experience, to make everything fast and easy and clean. But at some point everything changed: the tail started to wag the dog instead and development became JavaScript-first.

Just recently I started using ReactNative. I've been using React for years but this thing is a whole new world. There are tons of basic stuff which I don't know how to do. Using an SVG as a button is one of them. Find my solution below and expect more short #reactnative blog post soon.

We all know that one of the most challenging task in software development is state management. This is especially true for the JavaScript world. There are thousands of articles on this topic and so I decided to write another one 😁. I wanted to share my current thoughts on the different state types. I found that answering "What lives where?" question is far more important than the actual state management. Which more or less is an implementation detail.

This weekend I decided to play with the new kid on the block - Facebook's Recoil library for managing state. I did the trivial counter example to see how it works. It's pretty simple idea so I wondered how much it takes to replicate its features. I found the exact answer - 70 lines of code. Obviously, my implementation didn't cover everything but it was fun so I decided to share my findings.

(A side note: I did not look at the code of Recoil. I didn't want to be bias on how to write my version.)

Lea Verou, known in the community as the "Queen of CSS", shares her personal story about how she became a web developer. She discusses how her passion for computers began in her childhood and her dream of living outside Greece.

These days I had an interesting problem to solve. At work, on our staging environment, we have basic authorization. It works really well but for some older versions of Chrome we experienced a weird issue. The browser did not pass the authorization header. The app runs fine but as soon as it does a fetch request to a local endpoint the request fails with 401 not-authorized error. In the modern browsers that's not happening because the browser kinda knows that we came here with basic auth and automatically includes authorization: basic ... header.

I ❤️ markdown. I like its simplicity and minimalistic API which is good enough to cover most of needed HTML markup. At least for textual content. At work we have a small node based microservice that delivers data from Contentful in exactly markdown format. It's all working well but we started having cases where part of the text is in Contentful and the other part is in that microservice. For example when we have a button with a catchy design. We want to content manage the label of the button but the actual markup to be on our side.

We spent a day with Open Source-“Wunderkind” Max Stoiber in Vienna. Despite his young age of only 23, Max has achieved incredible things: he's created react-boilerplate and styled-components, his start-up, Spectrum, was recently acquired by GitHub and he gives talks all over the world. Learn more about his journey - and how he dropped out of university (twice!) - in this mini-doc.

I'm continuing to experiment with React and TypeScript. The weekend-long project this time was a Covid-19 data tracker. In this blog post I will share how I built c19stats.now.sh. I exposed the data as a public API at the same URL. I guess you, as many other people, follow the situation so you may want to glue your fingers on the keyboard and create something useful around the data. I got lots of fun playing with the diagrams.

В тези смутни времена се чуваме online с Радо Станков за да си поговорим за remote working. Не че по принцип не се чуваме така, но сега е малко по-различно. В този 24-ти епизод споделяме нашия опит в работа от разстояние. Приятно слушане.

These days working from home is a norm. We all know why. This f.cking virus is all over the globe. I bet there are tons of articles on how to work remotely efficiently but I wanted to give my two cents.

I'm now actively working on a VSCode extension. I started it as a theme but then decided to add some more features. Like for example a tin line on the left side of the editor marking the current function scope. In order to do that I had to analyze the current file's code and find the lines that are included in that scope. The obvious approach will be to translate the code to AST and then traverse the tree finding the information that I need. This however will require the usage of a language server which now I don't want to deal with. So I decided to explore a brute force approach. Looping over the string characters and finding balanced matches. I quickly wrapped it into a library. I called it Pairify. It consumes text and returns an array of pairs. This blog post will show you how it works.

Starring Lee Byron, Dan Schafer and Nick Schrock (co-creators of GraphQL) and other big names from the #GraphQL community, "GraphQL: The Documentary" explores the story of why and how GraphQL came to be and the impact it's having on big #tech companies worldwide, including Facebook, Twitter, Airbnb and Github.

With the help of Sarah Drasner, Taylor Otwell, Thorsten Lünborg and many others from the Vue.js community, Evan You tells the story of how he fought against the odds to bring Vuejs to life.

2020 for me started with the release of several OS projects. Two of them reached 100 stars in a week and I was thinking that would be nice sharing my workflow. Not like it is working every time, absolutely not, but leads to some good results.

I just started using TypeScript. I did couple of React projects and noticed a pattern in the setup. I decided to export that to a starter kit 👉 beginning. It is based on Webpack with Babel and TypeScript loader.

I just recently moved my outset.ws domain to Zeit name servers. That's my 13 years old domain which I'm not using it anymore. It makes sense to point to krasimirtsonev.com. The thing is that I have an email which is used all over the net. I of course want to keep that email. And suddenly I wasn't able to receive messages to it. I started missing some very important emails. Like bills that have to be paid and GitHub notifications.

87% of my readers are using Chrome on desktop. This means that I have the luxury to care less about performance. However I just recently found that this blog has 56 (out of 100) points on Google's pagespeed test. That's not good. The report says that my Disqus comments are blocking the main thread for ~900ms. I want comments on my blog but I also want my users to reach to content as quickly as possible. So, after so many years using Disqus I decided to break with it and use something else.

Two brothers caught in a time loop must traverse a series of maze-like events in order to prevent a catastrophic fire from occurring.

I just spent ~2 hours on this and I had to blog about it. I bet I will come back to the same problem and it will be nice to have a quick solution at hand. And the problem that I'm talking about is the non working Go to definition or Go to implementation feature of VSCode. Or in other words the JavaScript IntelliSense was not working for me. Of course it was annoying because I had to navigate to files manually via the folder tree on the left or typing the name of the file in the Cmd+Shift+P popup.

I'm working on a project in my own git branch. At the end of my working day I want to do one thing - run Prettier so my code is nicely formatted before I submit the PR for code review. Of course I know about the VSCode Prettier extension but right now my editor is kinda broken and I don't want to mess with it. I'm still on my branch and I run Prettier from the terminal. All good but the amount of changes that happened is so big that my 50+ loc updates are like a needle in a haystack. It is like that because apparently there are already malformatted files in the project. It is definitely not possible to understand what I did because of so much noise. So ... I want to run Prettier but only on the files that I touched in that particular branch.

I'm working on a small library that has a logger. I'm bundling the app to a single file and I want to disable the logger for the production version. In this blog post we will see how I removed the logger.log calls from my bundle using AST (abstract syntax tree).

The story follows a secret society whose purpose is to find people who don’t deserve to live and to kill them with their thoughts. The tension between the pessimistic protagonist and the liaison of the secret society comes to a head in a riveting twist.

Yesterday was one of those days. I stumbled a task and wanted to find the right tool for it. That same task is on my way at least twice a week and I always refuse to optimize it. Because it was a weekend I decided to spend some time and research a proper tool for the job. Well, I find nothing that suites my need. I time-boxed a hour and said F.ck it!. I will code it myself. That's how Hopa was born - a zero config CLI that runs JavaScript and TypeScript. Transpiles, bundles, watches and executes code.

Riew is a library based on communicating sequential processes (CSP). It is made to help with communication and synchronization between your view and business logic. It's distributed as a npm package, it has 0 dependencies and adds ~8KBs (gzip) to your application on production.

CSP is a formal language for describing patterns of interaction in concurrent systems. It's used in Go, Crystal, Clojure's core.async and a couple of other places. The idea in its core is nothing so complicated but it offers some interesting capabilities. Surprisingly enough it is not really popular in JavaScript. Recently I'm exploring this pattern and here are my findings.

In this article we will see some use cases of Riew. Those are patterns which I found repeating while using the library. There are other blog posts part of the same series and I will suggest checking at least this one so you get a basic understanding before jumping into the code snippets below.

Something bugs me last couple of years. I'm using React for some time now and there is always this doubt if I'm placing the business logic on the right place. I'm trying to be pragmatic, to follow best practices and listen what the community is saying. However, I still feel that something is not ok. This blog post presents the idea of the reactive view. That is nothing new per se but I came up with this term because it fits well in my idea.

I just finished reading My Decade in Review by Dan Abramov and as part of his article he mentions this talk by Bret Victor. I think it's amazing and want to keep a reference to it somewhere. What a better place than this 12 years old blog.

Епизод 23 на малко позабравения NADCAST е тук. Този път гости ми бяха Яни (https://remoteit.world/) и Ния (https://influencer.bg/). Поговорихме си за маркетинг, брандинг, hiring и работа от разстояние. Приятно слушане.

Just recently I became a fan of the iterable protocol. I knew about it for some time now but never actually integrated it on my own. I ended up using it to provide a nice API for one of my libraries and I thought that this approach worth sharing.

I really like Redux. I Love its ideas. The reducers for example - small pure functions that apply changes without side effects are nice way to model the mutations in the state. Redux also teaches us to use the one-direction data flow which makes our apps more predictable and stable. These two things fits well for what we are doing on the front-end - building user interfaces.

Of course there is nothing perfect and Redux as every other library has its own problems. In this article I want to explore some ideas for new APIs that will help solving the problems that I encounter. I’ll be happy to see your comments below.

Recently I stumbled upon on an interesting bug which reminded me what is actually happening with my components when React is rendering them.

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.

Last weekend I was part of the ReactNotAConf conference and this 22th episode was live recorded on stage there. Kudos for the organizers and the speakers. It was an awesome event and it looks like we've made a really interesting panels. Enjoy.

Една седмица преди React.NotAConf с Радо обсъдихме някой важни подробности около събитието. Ако се чудите за какво точно ще говорят лекторите или ако все още не сте решили какво да правите на 11 май изслушайте епизода. Ще се радвам да се видим в Interpred WTC.

I'm using Git and GitHub in particular a lot. And when I say a lot I really mean all the time. Recently I tracked a week of work and found that 62% of my working time goes into code reviews. Sometimes I'm checking out a branch locally and trying stuff but really most of my time goes into github.com. I spent some time analyzing why the code review process is so time consuming for me. I identified couple of reasons, made a tool and changed some of my habits. In this article I'll show you how I improved my code review speed and lower the time to 38%.

The hooks API is a wonderful idea. There are some slick patterns involved that push the React development to a more functional approach. I'm interested in trying that new API and decided to use it for my latest project. However, after a couple of days, it looked like I can't build my app only with hooks. I needed something else. And that's mainly because each hook works on a local component level. I can't really transfer state or exchange reducers between the components. That's why I created Jolly Roger. It has similar helpers but works on a global app level.

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

Пилотния за сезон 2019 епизод е със Стефан Кънев. Поговорихме си за мениджмънт и лидерство. Приятно слушане.

Ето един малък коледен подарък - епизод номер 19 на NADCAST. Последните няколко месеца съм на вълна продуктивност. С Радо Станков и Минко Гечев си поговорихме за TEA framework. Или казано по друг начин, как да намерим повече време (time), енергия (energy) и фокус (attention). Приятно слушане.

Recently I spent some time working on my own JavaScript playground called Demoit. Something like CodeSandbox, JSBin or Codepen. I already blogged about why I did it but decided to write down some implementation details. Everything happens at runtime in the browser so it is pretty interesting project.

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.

If you use React you probably know about the so called hooks. They were officially announced at this year's ReactConf by Sophie Alpert and Dan Abramov. Their presentation could be seen here. I, same as many others got intrigued by this new feature. A little bit confused by if I like them or not but kind of excited. This article pretty much sums up my thinkings around React hooks and aims to give a balanced opinion.

This episode is with Sara Vieira. She is doing a lot of interesting things with React, GraphQL, Apollo and with JavaScript in general. She's also part of bunch of conferences doing talks and workshops which itself is a big challenge. Happy listening :)

If your users deal with images (photos, product images, etc.) it will be great if they have the ability to apply some basic editing after upload, e.g. adjust brightness and contrast for sharper view, crop, add some text, etc. However, if image editing is not the primary feature of your product, the profit from investment in such secondary feature won't cover the costs. Integrating a 3rd party image editor appears to be a wiser choice.

След дългата, почти два месеца пауза, епизод 17 на NADCAST е с Радо Станков. Започнахме с някои много интересни новини като предстоящия NotAHackathon и VarnaConf. След това си поговорихме за различните по вид работни среди. През freelancer-ството до работата в продуктова компания.

Long long time ago in a kingdom far far away there was an app. The app was supported by the well known React and Redux families but there was a problem. It was damn slow. People started complaining and the app had to do something. It had to deliver its content quickly so it provides better user experience. Then the server-side rendering was born.

Много ценен разговор с Владо се получи. В този 16-ти епизод дискутираме code review процеси, навици, мотивация и като за финал малко за баланса в нашата професия. Надявам се да ви хареса.

Years ago when Facebook announced their JSX syntax we had a wave of comments how this was against some of the well established good practices. The main point of most people was that it violates the separation of concerns. They said that React and its JSX are mixing HTML, CSS and JavaScript which were suppose to be separated.

In this article we will see how React and its ecosystem has quite good separation of concerns. We will prove that markup, styles and logic may live in the same JavaScript land and still be separated.

Episode #15 of NADCAST was live recorded at ReactNotAConf conference in Sofia on 28th of April. After every presentation we've made a panel with the speaker and ask topic related questions. So, if you listen the whole episode you'll get a pretty good overview of what the conference was about.

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.

Стефан и Митьо споделиха солидни практики и опит в менторирането на по-начинаещи програмисти. Надявам се този 14-ти епизод да ви бъде полезен независимо на какво ниво сте.

MP3: http://nadcast.krasimirtsonev.com/StefanKanev_DimitarDimitrov.mp3

Фаталният епизод 13 на NADCAST е с моя добре познат събеседник Радо Станков. Основна тема на нашия разговор беше новата версия на React и предстоящите React.NotAConf (http://react-not-a-conf.com/) и Bulgaria Web Summit (https://bulgariawebsummit.com/) конференции.

Redux is a library that acts as a state container and helps managing your application data flow. It was introduced back in 2015 at ReactEurope conference (video) by Dan Abramov. It is similar to Flux architecture and has a lot in common with it. In this section we will create a small counter app using Redux alongside React.

Епизод номер 12 е с Димитър Димитров (Митьо). Поговорихме си за менторството и за това как трябва да се подхожда към начинаещите програмисти. Имаше и малко DevOps даже :)

Първия епизод за 2018 е с Мариан и Павел. Поговорихме си за Sashido.io, инфраструктури, наемане на хора и още нещо :)

On my machine I have four applications always open - VSCode, Chrome, iTerm and Slack. I spend most of my time in Chrome and VSCode. My editor is full with awesome extensions and I feel pretty good there. What I am doing for the browser is making sure that I have fewer tabs open and install only extensions that I really use. One thing though I can achieve so far. I can't find the perfect new tab extension.

(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.

Предколеден 10-ти епизод на NADCAST е с Радо Станков и Минко Гечев. Разговора започна с малко meta теми, но после си поговорихме за Angular, React и JavaScript като цяло. Приятно слушане и весели празници.

If you are writing React applications you probably know about higher order components or render props (which by the way I think is kind of a form of higher order component pattern). In both cases we have a component that encapsulates logic and passes props down to children. Recently at work we came to the idea that we may push this further and represent some functionalities which are out of React in the same fashion - with a single tag in our components tree.

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.

This article is about Stent - a Redux-liked library that creates and manages state machines. Stent implements some of the Redux’s core ideas and in fact looks a lot like it. At the end of this post we will see that both libraries have a lot in common. Stent is just using state machines under the hood and eliminates some of the boilerplate that comes with Redux’s workflow.

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.

Епизод 9 на NADCAST е с Радо Станков. Основно си поговорихме за React и нашумелите около библиотеката теми. Приятно слушане :)

If you write JavaScript today you probably use some sort of a transpilation tool. A tool that reads your hipster code and convert it to code that works in the browser. In this article we are going to see what is actually send to the browser and how exactly libraries like Babel polyfill some of the ES6 features.

Епизод 8 на NADCAST е с Александър Тодоров. Поговорихме си за тестване, QA, release процеси, малко за React. Оказа се че тестването в компании като RedHat може да бъде доста голямо предизвикателство.

I was doing a podcast episode with Kent C. Dodds when he mentioned README-driven development. And so I decided to try it out with a new library which I just started. Here’s what I found.

Episode 7 of my podcast with Kent C. Dodds. We had a nice chat about open source, teaching, React and Prettier.

Episode 6 of my podcast with Cole Peters. We had a nice chat about the good old days, designing for web and CSS.

Rakka is the first short film from Oats Studios.

Епизод 5 на NADCAST е с Христо Панайотов. Прави доста интересни неща по доста интересен начин. Поговорихме си за това как се случват по кретивните уеб сайтове в днешно време и малко за JavaScript stack-a.

Тази седмица мои гости бяха Мишо и Найден от Nerds2Nerds. Както всеки път така и в този епизод темите са малко на случаен принцип. Поговорихме си за интервю процеси, за remote work и къде е по-яко да се работи.

There are lots of things which I like in React. Mostly the fact that it teaches interesting patterns. One of my favorites ones is higher-order component. In this article we’ll do a couple of experiments and will see how powerful this approach could be.

Трети епизод на "NADCAST". Този път със Радо Георгиев. Радо преподава и програмира и компания движи и конференция организира и още какво ли не. Поговорихме си за доста неща и е трудно да ги изброя тук. Та изслушайте го целия епизод :)

Втори епизод на моя podcast наречен "NADCAST". Този път със Стефан Кънев си поговорхме за процесите в една компания. Надявам се да ви е интересно.

Това е един експеримент, който мисля от доста време. Първи епизод на моя podcast наречен "NADCAST". Поговорихме си малко с Радо Станков. Предимно за React.

A sci-fi short about augmented reality. "Strange Beasts" is an augmented reality game. It allows you to create and grow your own virtual pet. How far can it go?

I'm a proud father of two and programmer for more then 15 years. My kids are small so I'm really into parenting right now. A bit of a problem for me is to stay up-to-date with the latest technologies in the Web. I really love my job but I just don't have enough time to look after all these frameworks, libraries or tools. I used to read Twitter, monitor RSS feeds and spend hours reading Reddit or Medium. However, no time for that anymore.

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.

(This article is part of React in patterns series.)

React is highly composable. And the API that enables that is props.children. It gives us the power to create a placeholder that is later filled with content from the outside.

The first article on this blog is published on 22th of August 2008. It’s about a website which I saw at FWA. Eight years later I’m still publishing stuff here and because it is the beginning of a new year I decided to give you some statistics.

After my phone got stolen, I quickly realized just how much of my personal information and data the thief had instantly obtained. So, I let another phone get stolen. This time my phone was pre-programmed with spyware so I could keep tabs on the thief in order to get to know him. However, to what extent is it possible to truly get to know someone by going through the content of their phone?

React is probably one of the best choices for building UI. Good design, support and community. However, there are cases where we want to use an external service or we want to integrate something completely different. We all know that React works heavily with the actual DOM and basically controls what’s rendered on the screen. That’s why integrating of third-party components could be tricky. In this article we will see how to mix React and jQuery’s UI plugin and do it safely.

One of the ways to stay up-to-date with the latest technologies is to watch talks from popular conferences. Here are two of my favorite ones:

When we start using React we very soon also start asking questions. Where I’m suppose to put my data, how to communicate changes or how to manage state? The answers of this questions are very often matter of context and sometimes just practice and experience with the library. However, there is a pattern which is used widely and helps organizing React based applications - splitting the components into presentational and containers.

Long time I was searching for a good front-end framework. Framework that will help me write scalable and easy to maintain UI. Even though React is just a library for rendering it comes with so many benefits that I can easily say “I found it”. And like every thing that I use a lot I started seeing some patterns. Techniques that are applied over and over again and I see in the code of other developers. It’s time that I start documenting, discussing and sharing these patterns.

Amazing art direction and storytelling in this one of a kind 360-degree musical short film from Oscar-winning animator Patrick Osborne. Watch out, it's a tear jerker!

The new Jamie XX video clip directed by Romain Gavras will blow your mind without using any CGI, proving you don't need special effects.

I’m writing code for approximately ten years now and at some point the word “writing” became more important then “code”. I found out that it is easy to generate code but it is difficult to write code. Writing means creating something meaningful. Something that other human beings will read. The code is indeed sent to machines and they do understand ugly code. Not the same for humans though. An important part of our job is to make sure that our code is clear for other teammates.

The Adam demo is a real-time-rendered short film created with the Unity engine by our demo team. It runs at 1440p on a GeForce GTX980 and was shown on the booths at our Unite Europe conference.

The setup here is available at GitHub here.

Half an year ago I published A modern React starter pack based on webpack. The starter provides the basic tooling around React. However, I noticed that very often I need even less stuff than that. That’s usually when I want to hack something quickly. In this blog post we’ll see what’s the bare minimum to work with React.

What a nice improvements of Google Chrome's DevTools. Amazing stuff!!!

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.

One of the things that I really like at work is the fact that we spend time in research tickets. We have unknowns and we make a research to find out more information on particular topic. We then base our decisions on the results. Recently we had to decide whether to use an <iframe> for a third party widget development. I feel that the collected information may be handy to someone else so I decided to write it down here.

Last week I landed on an article by Manuel Wieser called Dominant Colors for Lazy-Loading Images and I found the topic really interesting. It’s about lazy-loading of images. Something that Medium is using.

You probably heard about Kik, NPM and left-pad saga this week. Shortly, a company Kik asked a developer Azer Koçulu to give the ownership on a NPM module. The module name matches the name of the company. The developer refuses and the company reaches the registry (NPM). The module was transfered to the company based on a NPM policy. The developer then decided to remove all his modules from the registry. The bad thing is that one of these modules left-pad is a dependency of many other modules. As a result of the un-publishing all the packages that depend on left-pad can not be built. Some really popular tools like Babel and React started getting broken builds.

Node has a wonderful debugger. As a front-end developer I’m mainly using Chrome’s tools but sometimes I run things in Node environment and this native feature comes handy. In this article we’ll see how to debug in the terminal using Node’s debugger.

It's finally done. My first self-publishing ebook is released. The book is available here. I'm running a free giveaway for the next five days. So, subscribe for my newsletter at this address http://eepurl.com/bKt0TD and you'll get a free coupon that will lower the price to 0$.

Destructuring is one of my favorite ES6(ES2015) features. It just shortens my code and helps me be more explicit with my statements. Let’s see it in action.

Did you know that in the next 30 years 50% of the jobs will go away because we'll get machines doing them. I have the good feeling that my job (programming) is not in those 50%. Or maybe it is :)

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.

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.

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.

(This blog post is inspired by A modern JavaScript router in 100 lines and heavily related to Navigo router project)

If you build single page applications you probably know that one of the must-have parts is the router. The bit that knows how to tweak the content of the address bar and notifies the rest of the system for URL changes. In this article we will discuss the various aspects of the routing in the browser.

Two months ago I published a starter pack for React based on webpack. Today I found out that I need almost the same thing but without the React bit. This simplifies the setup but there are still some tricky parts. So, I made a brand new repository webpack-library-starter and placed all the stuff that we need for creating a JavaScript library.

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.

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.

This is a quick post so I document my two hours research. I'm working on a open source library for routing in the browser. Or in other words JavaScript library that uses the history API. The thing is that locally I'm using Apache as a dev server and I wanted all the request to specific folder to be redirected to index.html.

The Flux implementation discussed in this article is available here github.com/krasimir/fluxiny. Feel free to use it in a browser directly or as a npm dependency.

I’m obsessed by making my code simpler. I didn’t say smaller because having less code doesn’t mean that is simple and easy to work with. I believe that big part of the problems in the software industry come from the unnecessary complexity. Complexity which is a result of our own abstractions. You know, we (the programmers) like to abstract. We like placing things in black boxes and hope that these boxes work together.

I hope you know about currying. If not then please read this book. It’s basically a process of calling a function with less parameters than it expects. Ok, not exactly calling the function but prepare another function that will run the original one. Some people call the returned function higher-order factory function. Really powerful concept.

In the slums of the future, virtual reality junkies satisfy their violent impulses in online entertainment. An expert player discovers that the line between games and reality is starting to fade away. 3DAR’s latest short film explores the frightening potential of our next technological revolution. Behind the scenes coming soon! Stay connected, but not too much ;)

I recently finished watching Mr. Robot. If you didn’t check out the show please do. Last few days I felt like I’m hacking something. Just like Elliot in MR. Robot. This blog post is about fixing a weird bug. Really strange problem with a failing HTTP request.

GitHub’s pull requests are an important part of my/our development process. That’s why I was thinking about creating a template that will enforce the standards.

While I was open sourcing react-place I noticed that there is some complexity around preparing the component for releasing. I decided to document the process here so I have a solid resource next time. You may be surprised but writing the working jsx file doesn’t mean that the component is ready for publishing and is usable for other developers.

Checkout React webpack starter in GitHub.

You know how crazy is the JavaScript world nowadays. There are new frameworks, libraries and tools coming every day. Frequently I’m exploring some of these goodies. I got a week long holiday. I promised to myself that I’ll not code, read or watch about code. Well, it’s stronger than me. React werbpack starter is the result of my no-programming week.

We had to update some of our old pages adding new elements. This means mixing old and new code. Placing HTML markup and JavaScript in legacy pages is not that difficult. Yes, it brings some issues but they are easily solvable. However, the CSS is a whole new story. That’s why I did CSSSteal. It helps me extract the needed styles.

When CommonJS was announced we all thought “Finally something that will organize our code”. However, there are some cons that we should be aware of. It’s not only unicorns and rainbows. In this article we will see how a simple require line makes our code difficult to test.

You probably know the famous quote that the code should be written for humans to understand and accidentally for computers to execute. Writing code that compiles is easy. Writing readable code is completely different thing. Working in a team is like sharing the kitchen with your roommates. You all should care for the dishes and keep clean. And it is not only because of the others but because of you. You don’t want your dinner in a mixed place and dirty dishes right.

You’ve probably heard of Browserify. It’s a nice npm module for bundling your JavaScript for a client-side usage. It lets you use similar to Node.js modular system but for the code running in the browser. I had few issues testing modules in an app that uses Browserify. So I had to learn how it works and probably hack it in order to solve my problem.

A really nice infographic for one of the most popular JavaScript client-side frameworks - Angular, Ember and Backbone.

So it's been a few months since I published something here. It’s not because I’m lazy (that’s true though) but because I was working on my second book. Now the book is almost finished and I’ll start actively blogging again. In this article we’ll see how to use the local storage of the browser as a communication channel.

I could split my programming experience in two parts. The first one is a little bit more creative. That's the time where the application still does not exist. You invent and architect the program. The second part is extending and fixing the already created system. They, these two parts, have their own interesting and boring sides. However, I believe that they both are in the essence of delivering quality software. This article focuses on bug fixing. It aims to give you bunch of advices how to properly handle the problems in your applications.

The year is 2005. At that time I was a student in Technical University of Varna. As every normal student I had to visit the building of the university from time to time.

I like npm and the fact that I can install tons of stuff. It’s great piece of software and helps me solve problems everyday. Yesterday I had to use a postinstall script and hit a problem.

Christmas is just around the corner. I thought that I should post something. Recently I watchedvideos from two big front-end conferences. So, here is my present for you. A few talks that I think worth attention.

Usually I don't write such articles but this time I'll share my story. I was going to fly from London to Bulgaria. The flight is two hours and a half which is (by my opinion) enough to get bored. When I was traveling from Bulgaria to London I used my phone a lot. I read lots of stuff for reactive programming, played few games, ate some snacks. However, for the way back I wasn't prepared.

I don’t think that we have to discuss the importance of having tests. That’s not something that we add to the project in addition. That’s something that the project is based on. And because testing is so important we have bunch of tools in our disposal. We all know (I hope) how to test our back-end code. However, once we move to the front-end is a bit different. At the moment we are working on a big single page application and testing is one of our main focuses. In this article you will see how to unit test our client-side JavaScript.

I’m reading and watching a lot of interesting things regarding client-side performance. I’m interested in the browser’s processes happening before and just after the page’s load. There are tons of stuff to think about. Before a couple of days, I joined the online workshop of Vitaly Friedman. I had a great time and learned some clever facts about performance optimization.

Every front-end developer that starts reading about CSS preprocessors thinks “Oh, finally variables in CSS". Indeed, the ability to create and use variables in CSS makes our code much more flexible. However, I think that there is no need to use a preprocessor to create flexible stylesheets.

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.

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.

You've probably heard about ToDoMVC project. It's same ToDo application made with different frameworks. It's interesting how the same problem is solved by different programmers following different concepts. This article is about making the ToDoMVC application with AbsurdJS.

The browsers nowadays are smart. They optimize everything and help us to produce better applications. They process our code as fast as possible and even on mobile devices deliver a pleasant experience. However, at the same time, it is possible to write buggy code and make the browser freezing. We are not talking about slowing down the rendering. We are talking about no rendering at all. There are cases where we want so much from the browser that it just can’t handle it.

The bug reporting is something very important for us. As developers, we produce code that should work everywhere. Not only on our machines. No matter how many times we test our application it often happens that it does not work properly for the client. We all know how helpful is an email with text “It does not work. Fix it ASAP!”. Usersnap is amazing tool that removes the gap between you (the developer) and the non-techy guy from the other side.

CSS is easy? CSS is messy! And as a project grows, it only gets messier. You find yourself throwing !important at everything or fighting with long selectors just to get a style to overrule another. Projects eventually become unmanageable and you pray for the next redesign when you can burn it all down and start from scratch.

Building high performance sites and apps is crucial to your success on the web, and never more so as people start using smartphones as their primary means of internet access. But how can you make sure you're squeezing out every last bit of performance from your projects? In this talk we'll look at the tools you need to succeed and how to integrate them into your workflow.

It has been 10 years since Packt Publishing embarked on its mission to deliver effective learning and information services to IT professionals. In that time, it has published over 2000 titles and helped projects become household names, awarding over $400,000 through its Open Source Project Royalty Scheme.

It's again Sunday and I'm planning to watch talks. Last week few conferences shared their recordings. I got some nice videos from Twitter and again my bookmarks bar is full with YouTube and Vimeo links. So, it's time to clear it a bit and make room for the next weekend. Here is my plan:

These are screencasts from the this year's Scotland JS conferences. It happened on 9th and 10th of May. If you are a JavaScript developer you will probably want to see the talks.

Us JavaScript programmers like to use words like, "event-loop", "non-blocking", "callback", "asynchronous", "single-threaded" and "concurrency". We say things like "don't block the event loop", "make sure your code runs at 60 frames-per-second", "well of course, it won't work, that function is an asynchronous callback!".

This blog has 460 posts. In some of them, I need to show video clips demonstrating some feature or browser behaviour. I found that it was much better to do that in an animated Gif. However, they play automatically which is kinda annoying. Imagine that we have ten Gifs on the page and while you are reading they all blink or show moving content. It's like having a page full with banners.

You may not realize it but we, as web developers, have special powers. We could control the Web. Here are two annoying things that I was able to workaround just because I know how to use DevTools.

Jenn Schiffer introduces jortSort. If you want to know what is all about, check out the talk.

Google Chrome is my favorite browser. I'm spending a big part of my working hours there, so it makes sense to use it for everything. Last week I posted "Sorry, Chrome killed the terminal". The article was about Yez!, an extension that brings terminal-liked functionalities to the browser. Today, I'll show you how I use Chrome in my Node.js development workflow.

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.

That's right. I'm not using the terminal anymore. Instead of that I'm using Chrome. Yes, the Google's browser. There is an extension called Yez! that connects to a Node.js module via web socket. It executes the shell commands and returns the result. And even works under Windows.

These days I spent some time working on Yez!. Chrome extension whose main role is to replace the annoying switching between the terminal and the browser. It uses Node.js module to run shell commands. So, I had to deal with child processes, and I decided to document my experience.

We all know what responsive means nowadays. We, as developers, normally develop responsive applications. There is a dozen of instruments helping us achieving our goals. Some of us use extensions and even pay for them. However, I'm using one thing - Google Chrome browser. In this article, we will see what the Chrome's capabilities for testing responsiveness are.

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.

Today I landed on the site of JSConfEU. I was browsing and opened this video. What a great surprise!

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.

Before a couple of weeks I published Techy. It's a flat CMS based on Node.js and Markdown. I made it because I wanted to write my articles in Markdown format and avoid the annoying publishing workflow which I'm using now. I feel that it's not very clear how Techy works and decided to create a simple blog illustrating the processes.

I just finishing reading Getting Started with Grunt: The JavaScript Task Runner. The same book that we (I and Packt publishing) run a contest for. You could still joint it here and win a free copy.

A conference with a great format. It's more like a discussion panel. It's really informative. Some of the top developers nowadays talk about the future of the Web.

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.

The off-canvas menu is pretty popular nowadays. You know, the little button in the right upper corner which opens the navigation with a slide-in effect. That's what we are going to build in this article. The interesting things is that we are not going to use CSS neither HTML, only JavaScript.

The this keyword is always important in JavaScript. I'll admit that it took me some time to actually understand how it works. You know, sometimes JavaScript is all about the scope. Where you are and what you have an access to. This article is about the bind function. Something which I use very often.

If you believe in responsive design you probably use a lot of media queries. That's a CSS feature which gives us the power to add something like if statements. We are able to apply rules only if the current page meets certain conditions. In this article I'll show you how I use media queries in JavaScript.

If you build web applications you probably communicate with the DOM a lot. Accessing and manipulating DOM elements is the thing which we do almost every day. Very often we collect information from different controls, we need to set values, change the content of div or span tags. Of course there are million libraries which handle these actions. The most popular jQuery, is de factor a standard. However, sometimes you need something smaller. In this article we will build our own class for managing DOM elements.

This blog post is part of series about AbsurdJS. I'll continue filling the library with small and self organized black boxes. In the last article we talked about creating a JavaScript router. This time we will go through the process of making Ajax requests.

(The router here is now placed in its own project - Navigo. There is also another article Deep dive into client-side routing which you may find interesting)

Nowadays the popular single page applications are everywhere. Having such application means that you need a solid routing mechanism. Frameworks like Emberjs are truly build on top of a Router class. I'm still not sure that this is a concept which I like, but I'm absolutely sure that AbsurdJS should have a build-in Router. And, as with everything in this little library, it should be small, simple class. Let's see how such a module may look like.

I'm currently working on the official site of AbsurdJS. There are a lot of code samples out there and I wanted to present them in JSBins.

"I made it for myself and for anybody who is in doubt with his/her creative career. I also think that Ira Glass' message isn't only limited to the creative industry. It can be applied to everyone who starts out in a new environment and is willing to improve."

This seems like a trivial task. However, it is not. There are few popular solutions, but they have a big problem and if you use them a lot you will spot the issue.

Today I had to rename a bunch of image files to the same names, but in lower case. Here is how I did it.

I'm writing a lot of JavaScript these days. Even if the project is not Node.js based I'm using it for processing some tasks. At the moment most of my projects use GruntJS. Today I spend some time adding SASS to my workflow.

I like the quote that the programming is all about managing complexity. Maybe you've heard that the computer world is a giant construction of abstractions. We simply wrap things and produce new tools over and over again. Just think for a minute. The languages which you use have build-in functionalities and they are probably abstracted functions of other low level operations. It's the same with JavaScript.

That's one of those blog post which I'm using as documentation. When I find a bug and I fix it I feel that I have to write the whole process somewhere, because if I meet the same problem in the future I'll really want to save some time. Today I open my Flash CS5 and apparently I can't paint on the stage.

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.

I'm still working on my JavaScript based preprocessor - AbsurdJS. It started as a CSS preprocessor, but later it was expanded to CSS/HTML preprocessor. Shortly, it allows JavaScript to CSS/HTML conversion. Of course, because it generates HTML it was normal to act as a template engine. I.e. somehow to fill the markup with data.