Posts:

Hexagonal Architecture by example - a hands-on introduction

When you go through articles related to Hexagonal Architecture (HA) you usually search for practical examples. HA isn’t simple, that’s why most trivial examples make readers even more confused, though it is not as complex as many theoretical elucidations present it. In most posts you have to scroll through exact citations or rephrased definitions of concepts such as Ports and Adapters or their conceptual diagrams. They have already been well defined and described by popular authors i.e. Alistair Cockburn or Martin Fowler. I assume you already have a general understanding of Domain Driven Design and that you understand terms such as Ports and Adapters. I’m not a HA expert, yet I use it everyday and I find it useful. The only reason I write this post is to show you that Hexagonal Architecture makes sense, at least if your service is a little more than a JsonToDatabaseMapper.

Migrating to Service Mesh

This year Allegro.pl turns 21. The company, while serving millions of Poles in their online shopping, has taken part in many technological advances. Breaking the monolith, utilising public cloud offerings, machine learning, you name it. Even though many technologies we use might seem as just following the hype, their adoption is backed by solid reasoning. Let me tell you the story of a project I’ve had the privilege of working on.

The problem of immutability in Java

As a developer interested in both web technologies and game development I always found myself disagreeing with a large part of articles about using a particular technology to solve some problems. While such articles are often true, they often skip some important details that make given solution unacceptable in some other cases. And in this article I will try to look at immutability in a negative way from game development perspective and how it can affect web services too. It is always more fun to look in a negative way at something everyone loves ;)

Understanding accessibility

The group that you could help is huge. The Polish Association of the Blind reports that there are more than 3 million people in Poland with visual impairment and 42 thousand with complete blindness (based on official, national statistical data of 2016 - not so fresh; still, it is not better in 2020, so…). These numbers do not include people with other problems, for example, those resulting from severe sickness, with movement disabilities, or with learning problems, older or just foreigners, who are not fluent with the language. All of them, and many more, are not able to use digital products the way people without disabilities do.

Using dotnet new templates to streamline microservices development

You may not know this, but there is a part of Allegro codebase which we started developing in C# due to some special requirements. This implies new programming opportunities and challenges — one of these is creating a completely new .NET Core starter project. Let’s explore one potential solution: dotnet new templates.

allegro.tech

At Allegro, we build and maintain some of the most distributed and scalable applications in Central Europe. This poses many challenges, starting with architecture and design, through the choice of technologies, code quality and performance tuning, and ending with deployment and devops. In this blog, our engineers share their experiences and write about some of the interesting things taking place at the company.