Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Have you ever wondered what happens with the variables you define in your Golang (Go) programs? Do they exist forever, or are they recycled at some point? Where do they live in memory and how are they managed?| blog.allegro.tech
We often hear about the importance of exchanging knowledge and practices between different teams. However, less often do we hear concrete suggestions for how to do it. In this article, we discuss one of our practices to address the problem.| blog.allegro.tech
Microservices are now the mainstream approach for scalable systems architecture. There is little controversy when we are talking about designing backend services. Well-behaved backend microservice should cover one BoundedContext and communicate over the REST API. Things get complicated when we need to use microservices as building blocks for a frontend solution. How to build a consistent website or a mobile app using tens or sometimes hundreds of microservices?| blog.allegro.tech
Some books on IT topics become outdated right after they are published while others stand the test of time. One of the latter is The Pragmatic Programmer. From Journeyman to Master by Andrew Hunt and David Thomas.| blog.allegro.tech
In the previous post - part 2, we covered more common Gradle mistakes and how to fix them. In the last part of this triplet, we will share our favorite Gradle plugins that can help you avoid some of the mistakes we discussed in the previous posts!| blog.allegro.tech
Have you ever struggled to identify which REST API is being tested in your integration tests? In this article, you’ll learn a clean and readable way to call REST APIs within your integration tests. The goal is to make the WHEN section of the test clearly show which API is called and in what context, while hiding all technical details.| blog.allegro.tech
Training Machine Learning models on big data isn’t just about fitting the model itself — it’s about efficiency at every stage of the process. While much attention is given to optimizing model training itself, the earlier phases can be just as, if not more, critical to the overall performance. In this article, we take a deep dive into what happens before we actually invoke model.fit(), focusing on the data pivoting stage. We are taking you on a journey through various pivoting solutions,...| blog.allegro.tech
In the previous post - part 1, we covered common Gradle mistakes and how to fix them. After a review and feedback from the community, we decided to extend the list with more tips and best practices.| blog.allegro.tech
In this blogpost we want to introduce the topic of using a Large Language Model (LLM) as an evaluator — a novel approach to tackling the complexities of evaluating advanced machine learning systems, particularly in tasks like Automatic Summarization, Text Generation, and Machine Translation, where traditional metrics struggle to capture nuances like cross-lingual accuracy and bias detection.| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
This article discusses the dual-use dilemma of AI, focusing on China’s approach and the challenges of balancing innovation with security risks, particularly the blurred lines between civilian and military applications.| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
In this article, we want to share our journey of searching for optimizations in one of Allegro’s main microservices: opbox-web. You’ll read about the issues we had to deal with and how we managed to overcome them — together with a few surprises along the way and even one golden rule broken.| blog.allegro.tech
Many companies face the challenge of efficiently processing large datasets for analytics. Using an operational database for such purposes can lead to performance issues or, in extreme cases, system failures. This highlights the need to transfer data from operational databases to data warehouses. This approach allows heavy analytical queries without overburdening transactional systems and supports shorter retention periods in production databases.| blog.allegro.tech
When we think about the Circuit Breaker pattern, we instantly associate it with the HTTP client. Just make some annotation or wrapper and proceed with coding. In this article, I will encourage you to use this pattern to resolve business problems. Based on a live example from Allegro I will show you how to use the implementation of CircuitBreaker from Resilience4j library for cases other than HTTP calls.| blog.allegro.tech
As part of Allegro Hacktoberfest celebrations, Andamio Task Force (the team responsible for Andamio, a set of common libraries used by most JVM projects at Allegro) posted the following message on our social platform…| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Did you know that in October this year, DRY principle will celebrate its 25th anniversary? It was proposed by Andrew Hunt and David Thomas in The Pragmatic Programmer book in 1999. 25th birthday is quite a good reason to celebrate, isn’t it? At least, it’s a good opportunity to bring this principle back into the spotlight and to discuss how to use it properly.| blog.allegro.tech
At Allegro, we continuously improve our development processes to maintain high code quality and efficiency standards. One of the significant challenges we encounter is managing code migrations at scale, especially with breaking changes in our internal libraries or workflows. Manual code migration is a severe burden, with over 2000 services (and their repositories). We need to introduce some kind of code migration management.| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
In one of our core services, the execution of a single unit test took approximately 30 seconds, while a single integration test ranged between 65 and 70 seconds. Running the entire test suite took circa 6 minutes.| blog.allegro.tech
Hi, I am Magda and I will tell you a story about coming back to work after a break of 21 months and 2 days. Everything here will be a subjective perspective about my experience.| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
Are you, as a test automation engineer, tired of Selenium’s flakiness? Are you seeking a better tool to automate your end-to-end tests? Have you heard of Playwright? Perhaps you’ve encountered opinions that it is only worth using within a Node.js environment. I have. And as a tester, I decided to verify if this is true. If you’re interested in the results, I encourage you to read the following article.| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
This article is a case study of how we improved stability in our critical application. It’s mostly a technical analysis of what happens in fresh Java based instance, how JIT Compiler toyed with us at application start and how we learned to control it.| blog.allegro.tech
Welcome to our technology blog. We use Open Source solutions on a daily basis here at Allegro. Why not work on our karma and give something in return?| blog.allegro.tech
If you have experience with Event Storming and have ever found yourself wishing there was a way to document the insights gathered during a session, or wanting to communicate the process to other team members, then I have a solution for you. This idea can be expressed in a famous saying: One picture is worth more than a thousand words.| blog.allegro.tech
Site performance is very important, first of all, from the perspective of users, who expect a good experience when visiting the site. The user should not wait too long for the page to load. We all know how annoying it can be when we want to press an element and it jumps to another place on the page or when we click on a button and then nothing happens for a very long time. The state of a site’s performance in these aspects is measured by Web Vitals performance metrics and most importantly b...| blog.allegro.tech
In this article we’ll present methods for efficiently optimizing physical resources and fine-tuning the configuration of a Google Cloud Platform (GCP) Dataflow pipeline in order to achieve cost reductions. Optimization will be presented as a real-life scenario, which will be performed in stages.| blog.allegro.tech
One tech blog/newsletter gained traction and popularity for a couple of years now: Pragmatic Engineer.| blog.allegro.tech
The purpose of this article is to present how to design, test, and monitor a REST service client. The article includes a repository with clients written in Kotlin using various technologies such as WebClient, RestClient, Ktor Client, Retrofit. It demonstrates how to send and retrieve data from an external service, add a cache layer, and parse the received response into domain objects.| blog.allegro.tech
This story shows our journey in addressing a platform stability issue related to autoscaling, which, paradoxically, added some additional overhead instead of reducing the load. A pivotal part of this narrative is how we used Couchbase — a distributed NoSQL database. If you find yourself intrigued by another enigmatic story involving Couchbase, don’t miss my blog post on tuning expired doc settings.| blog.allegro.tech
At Allegro, we use Kafka as a backbone for asynchronous communication between microservices. With up to 300k messages published and 1M messages consumed every second, it is a key part of our infrastructure. A few months ago, in our main Kafka cluster, we noticed the following discrepancy: while median response times for produce requests were in single-digit milliseconds, the tail latency was much worse. Namely, the p99 latency was up to 1 second, and the p999 latency was up to 3 seconds. This...| blog.allegro.tech
Have you ever thought about ways of reducing repetitive, monotonous tasks? Maybe you would like to try to automate your own tasks? I will show you what technology we use at Allegro, what processes we have automated, and how to do it on your own.| blog.allegro.tech
This story shows how we strive to fix issues reported by our customers regarding inconsistent listing views on our e-commerce platform. We will use a top-down manner to guide you through our story. At the beginning, we highlight the challenges faced by our customers, followed by presenting basic information on how views are personalized on our web application. We then delve deeper into our internal architecture, aiming to clarify how it supports High Availability (HA) by using two data center...| blog.allegro.tech
Ready to turn web accessibility from a headache into a breeze? Join us as we demystify WCAG, explore its latest 2.2 version, and gaze into the future of digital inclusivity. Get ready for a journey that’s as enlightening as it is entertaining!| blog.allegro.tech
Icons are an integral part of most modern UIs. What is the best way to embed icons nowadays?| blog.allegro.tech
The idea for this article arose during a meeting where we learned that our supervisor would be leaving the company to pursue new opportunities. In response, a colleague lamented that what we would miss most is the knowledge departing with the leader. Unfortunately, that’s how it goes. Not only do we lose a colleague, but we also lose valuable knowledge and experience. However, this isn’t a story about my supervisor; it’s a story about all those individuals who are experts in their field...| blog.allegro.tech
