Windows’ window usability protip

Having opened multiple windows of the same app usually gorups them together as one button on the taskbar. Clicking it opens a preview of them and you may choose what window you would like to open. But there is a better option. The alternative UX is to open the last opened window on the first … Read more

New headphones

After living years with wires I realized that I need to switch to wireless mode. Having wired headphones makes me less moving in the office – either less going to bathroom or less going for water to drink. I want to change this. Next, there are too many wires on my desk. Years ago I … Read more

Success & logic error propagation in Kotlin

In Kotlin, the expected code-flow should not use exceptions. The non-success code flow should be propagated through return type to be well-documented, strictly & statically typed. This post should be a practical guide after you have read Elizarov’s great post on Kotlin and Exceptions. Be aware that this post talks about domain errors, as described … Read more

PHP wish-list

Random list of missing language features in PHP. I do mostly Kotlin nowadays, so this is quite inspired by that language. I think these features could be (somehow) “easily” added into PHP. No new keyword It removes unnecessary keyword, allows to easily chain method call. This cool feature also allows a nice trick – using … Read more

Variance Elsewhere

The last post was mainly about the variance explanation and it was using Kotlin. But what about other languages? Let’s explore together. TL;DR Language Generics dec. out dec. in use out use in type erasure break out rules Variance available on Kotlin ✔️ ✔️ ✔️ ✔️ ✔️ ✔️ ✔️ classes, interfaces Java ✔️ ❌ ❌ … Read more


A lot was written about variance and its application in generics. This is another trial to explain variance and its practical usage. Let’s explore this using Kotlin. This article expects basic knowledge about generics. Variance is a powerful way to allow your code to do more. It is most obvious when you consider generics with … Read more