• Latest post Psychological needs at work

    This is a post for those seeking to accomplish business goals and ensure stability of the solutions developed while maintaining focus on people. The model of three basic psychological needs that I’m presenting here may be useful for leaders, agile coaches, and scrum masters. I also encourage developers to do some self-reflection. This is the knowledge I’ve gained at the World Conference of Transactional Analysis in Berlin. Transactional Analysis (TA) is a theory of interpersonal relationships developed by Eric Berne which has a practical application in various fields, including organizations.

  • How to approach testing in development process?

    Application release process, or in fact software development process, as a release is the final stage of application development, is not an easy thing. Books and IT websites discuss many approaches and each has its supporters and opponents. On the one hand, you have product owners, project managers and customers who want a ready-to-use application as soon as possible. On the other hand, we developers and testers, would like to release an application of the highest quality, which may affect the delivery time. Balancing these needs is a hard nut to crack. Usually, both sides need to make some compromises to establish a common way of working. For developers and testers, it involves answering several questions concerning software development methods, skills, use of manual or automated testing, and storage of test cases and test logs. In this article I describe best practices and tips for starting a new project. I think that by following them, you will make the software development process as effective as possible and adjusted to conditions of your project.

  • Mesos Executor

    Apache Mesos is an open-source project to manage computer clusters. In this article we present one of its components called Executor and more specifically the Custom Executor. We also tell you why you should consider writing your own executor by giving examples of features that you can benefit from by taking more control over how tasks are executed. Our executor implementation is available at github.com/allegro/mesos-executor

  • This Fall digest

    Some of our engineers run their own tech blogs. We encourage them to move here, but for various reasons, they prefer to publish on private blogs. We respect their decisions. What we can do is to gather all the blog posts published by allegro.tech engineers around the web in the one place.

  • Golang slices gotcha

    In this post I present a story of a bug that hit us recently. Everything was caused by unexpected (although documented) behavior of Go built-in function append. This bug has lived silently for nearly a year in allegro/marathon-consul. Ensure you run the latest version.

  • Presto - a small step for DevOps engineer but a big step for BigData analyst

    I bet you have found this article after googling some of the issues you encounter when working with a Hadoop cluster. You probably deal with Hive queries used for exploratory data analysis that are processed way too long. Moreover, you cannot adapt Spark in your organization for every use case because of the fact that writing jobs requires quite strong programming skills. Clogged Yarn queues might be your nightmare and waiting for the launch of the container when you run even a small query drives you mad. Before we deployed Presto — a Fast SQL engine provided by Facebook — our analysts struggled with these problems on a regular basis. Introduction

  • The Agile Testing Days Conference - Potsdam 2016

    Last year Agile Testing Days Conference was held between 6th and 8th December in Potsdam, Germany. According to statistics provided by organizers there were around 600 attendants and about 30 speakers in keynotes / workshops. During the whole event around 22 different workshops took place, 9 keynotes and around 30 other speeches / presentations divided into 7 parallel tracks. I had the opportunity to attend the first two days of the conference and in this article I’d like to share with you a short review of the most interesting sessions and my impressions about the event.


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.