Configuration properties is a great feature in Spring Boot. In a monolithic long-time running application, we often want to change the application settings. Those changes must be persisted to survive the application restart. We can use environment post-processing for that. This post describes how. Let’s start slowly; consider a simple…

Serialization is a great thing and a revolutionary feature of Java from the early days, but it does have some flaws. Among others, there are serious security issues I want to address in this post. The problem A typical example of a security issue is a communication via network using serialized Java…

Frameworks are good stuff, at least for middle to big enterprise applications. One doesn’t want to reinvent the wheel. Aspects like security, caching, monitoring are hard and it’s easy to get them wrong if implemented from scratch. On the other hand, there are valid use cases where you probably don’t…

Why is object-oriented programming still the best we have and how can it help us build well-designed microservices? — It is 2022, IT has already eaten almost the whole world and we have developed tools that make paradigms from the 60s such as OOP seriously outdated, right? Well, not really. At least in the mainstream, object-oriented design offers the most beneficial approach for software development from code to system…

Useless and impractical, yet beautiful, esoteric programming languages. — Esoteric programming languages, esolangs for short, are computer programming languages created mostly just for fun. They are usually very impractical, hard to write or even read, but always funny, lovely, weird, or in some other way interesting. Some esolangs are meant as an exploration of alternative ways to design programming…

Getting started with WebAssembly. — This is the first part of a series about programming in WebAssembly (Wasm) for beginners. The goal is to give you the first impression of what Wasm is and how it can be beneficial for your own projects. The further the series goes the deeper we will delve into the…

A series of learning texts covering the first steps with WebAssembly for complete beginners. Some time ago I started learning WebAssembly as an absolute beginner. It has been an exciting but not so simple journey. I decided to publish my continuous and probably neverending notices to make your learning path…

>> Originally published on my blog. << As I was finishing my blog post about defining service boundaries, I had a very strong feeling that there must be some abstract concept of what I was trying to explain using actual examples… Of course, there is! It is the concept of…

The Interface Segregation Principle (ISP) is the “I” in the SOLID acronym and states that clients should not be forced to depend on methods they don’t use. It attempts to decouple clients from unnecessary details. The Problem Consider a typical violation of the ISP (in Java): class UserService { User…