Illustration by Paula Ciastek

In the last few years, web developers have become more aware of performance and loading issues in web applications. The complexity of web apps has increased so much, that making an application overwhelm a user’s device is pretty easy. Luckily for us, browser vendors noticed this risk, and they started to educate us about how to care more about performance and why it’s important for web users.

Getting the best performance and load times can be very challenging. …


Thanks to Tomasz Cichos

As a developer, you may know that performance is a crucial factor that decides if a user willingly uses your application. No one wants to use a sluggish app, neither you nor the user of your app.

Maybe you think that improving performance is only about compressing assets and code optimization. Well, there is a huge part of the topic of performance which is often ignored, perceived performance.

Perceived performance describes how fast your app is in the user’s opinion. In other words, performance is measured not by some objective metrics but by user’s feelings and opinion.

Luckily, there are…


Now is the best time to be a Web Developer. We have access to plenty of APIs, which helps us in building outstanding web applications. With these new technologies, we can quickly do tasks such as DOM traversing, animations or even watching for changes in the document. Lately, new useful API appeared the Intersection Observer API.

What is Intersection Observer?

Element’s presence detection has always been a difficult task to do. Mostly, you needed to read the element’s bounding rectangle every time the scroll event was called. …


One of the latest technologies that will change interactions between humans and computers is definitely Virtual Reality. It’s not a new medium, but due to rapid technology progress, VR’s popularity is thriving like never before. Alongside with Augmented Reality, VR seems to be the next computing platform. Now, thanks to browser vendors’ effort, this technology is at our fingertips.

WebVR, recently renamed to WebXR (see why here), enables building VR experiences using the browser’s environment. This allows us to make VR applications that can run on various devices. …


Illustration by Paula Jenda

Even if you now build your applications using a popular framework, like React, Angular or Vue.js, you still need to add some styles to them. Depending on the technology you use, you need to write your styles in a specific way. For example for React, due to it’s component nature, it’s better to write styles using CSS modules. If you want to use brand new CSS features, it would be wise to use CSSNext. Don’t forget about good ol’ CSS preprocessors, like Sass or LESS. You may think - so many tools, I bet writing styles is different for each…


Image by Konrad Księżopolski

It’s common that website should be accessible for mobile devices. Today we more often use our smartphones or tablets to explore Internet. Users demand from web applications to be mobile-friendly. That’s why following Responsive Web Design rules is a must if we want to encourage people to use our app.

Although RWD became a standard W3C (World Wide Web Consortium) tries to introduce new patterns or tools, which help adjust web apps for mobile devices. Google, promotes usage of modern web technologies in series of articles. Moreover, Google introduced it’s own solution to accelerate web apps for mobiles, the AMP…


In ’80s Disney published a book titled “Disney Animation — the illusion of life”, which covers 12 principles of good animation. Even though, those principles were made with cartoons in mind, they apply pretty well to Web Design & Development too. Here are 4 of them which, in my opinion, can make your web animations much more attractive.

The modal animation presented below is a standard CSS fade-in and fade-out effect. Standard is the keyword here. We’ve seen that many times and it’s fine. Nothing special. Like most animations used on websites it doesn’t have any purpose. Developers add them…

Mirosław Ciastek

Front-end Developer ♦ Passionate about performant web apps and beautiful UIs

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