Authors

  • Adam Dubiel

    Adam is the library guy, who loves designing reusable software components with minimal dependencies, maximal usefulness and user friendly API. At Allegro he leads team responsible for creating internal services-for-services and tools that make development of microservices easier, the most significant one being Hermes.


  • Adam Dudczak

    Team manager in allegro.pl, on a daily basis I work on improving search experience in the biggest ecommerce site in Poland. I am professionally involved with Java and related technologies since 2004, currently focused on search and information retrieval. Organizer of GeeCON conference and former leader of Poznan Java User Group.


  • Adam Medziński

    Gopher working at Allegro for over 5 years, interested in container orchestration tools. Open source fan and occasional contributor.


  • Adrian Rydzyński

    Front-end Software Engineer who is interested in the JavaScript technologies - frontend, backend and mobile. Big fan of Angular, TypeScript and RxJS.


  • Aleksandr Serbin

    Software engineer at Developer Experience Team. Allegro-rewrite founder.


  • Aleksandra Kulesz

    New to the IT world and fascinated by the possibilities offered by the power of coding! She works as a Junior Software Test Engineer and is eager to expand her knowledge in the field of testing and QA. Practice makes perfect, so in her free time she tests Lego blocks with her family.


  • Aleksandra Osowska-Kurczab

    Senior Research Engineer in the Machine Learning Research team, working on large-scale recommendation systems. She’s pursuing her PhD in Computer Science at Warsaw University of Technology on deep learning in medical image analysis. AI enthusiast and geek.


  • Aleksandra Wasielewska

    Product Manager who is passionate about technology and people. At Allegro she takes care of checkout and payments areas where she addresses the needs of several million Allegro users. Agile enthusiast in every way, she enjoys spending time traveling around the world, reflecting cultural contrasts in the day-by-day life, as well as in the products.


  • Alicja Antkowiak

    Alicja is UX researcher in Allegro Group with cognitive science background. She is a big fan of data-driven decision-making and common sense.


  • Alicja Halamska

    Software engineer and an enthusiast of intricate problems whose solving gives her the greatest satisfaction. She enjoys learning new technologies and analyzing their differences and similarities. She laughs a lot and loves hiking in the mountains in her private time.


  • Alicja Rączkowska

    Senior Research Engineer in the Machine Learning Research team at Allegro, where she works on applying and advancing NLP methods in the e-commerce domain. Obtained her PhD from the University of Warsaw, where she focused on machine learning methods for histopathology.


  • Andrzej Winnicki

    In Allegro Group since 2013. Software Engineer with 7 years’ experience building code, architecture and technical solutions. Big fan of Agile movement, Scrum framework, Lean Startup and customer-oriented development. Focused on improving processes, interactions inside teams and applications’ user experience.


  • Andrzej Wisłowski

    Andrzej works as a software engineer. He is interested in developing and designing search engines and NoSql solutions. At Allegro, he works in the team that delivers the search engine.


  • Anna Stanisławska

    Junior Product Manager in Transaction area, taking care of purchase and post-purchase processes. Product design and technology enthusiast focused on buyers’ needs.


  • Anna Wróblewska

    Ania achieved her PhD in computer science in 2008 at Warsaw University of Technology. Her interests concentrates around information retrieval, semantic understanding of image and text. At Allegro she works as an expert in machine learning algorithms, she designs specialised methods and makes a lot of analytical tasks. She tries to bridge the gap between business, the world of programmers and her scientific passion. Privately she is a happy wife and a mother of great children from adolescence to a kindergarten guy.


  • Artur Stępniewski

    Artur is an Android developer working at Allegro Group. Seeks ways of increasing code quality and helping developers avoid repetitive tasks. He’s passionate about motorsports and snooker.


  • Barbara Szott

    Senior Front-End Software Engineer. At Allegro she takes care of Metrum Design System and UI React components library based on Metrum. Huge fan of nature, yoga, meditation and western riding 🐴


  • Bartłomiej Bęczkowski

    Bartek is a software engineer who works on the Allegro experimentation platform. He is allergic to the status quo.


  • Bartłomiej Ignasiak

    At Allegro Group since 2009. At work he is interested in highly scalable architectures, microservices, Cassandra database, all technologies around JVM and all aspects of software creation. After hours he writes games and AI systems. At Allegro, he is a Solutions Architect for the users domain.


  • Bartłomiej Mazur

    Backend developer and wannabe gamedev, also loves to break the JVM and find every hidden detail in it. In free time, he loves solving issues that no one should have with unsafe, reflections and agents on stackoverflow.


  • Bartosz Balukiewicz

    Bartek is a Software Engineer focused on backend technologies, but also interested in dealing with big data. Likes to observe how teams work. At Allegro, he works on Allegro Smart! and Delivery Experience.


  • Bartosz Gałek

    Editor

    Software Developer at Allegro, engineer with devops flavor. Believes that there is always a place for improvement; likes to try new technologies and languages. Open source fan and occasional contributor.


  • Bartosz Walacik

    Former editor in chief

    Software engineer with 15+ years of professional experience. He focuses on lightweight and modern technologies around JVM. At Allegro, he works as a development team leader. JaVers project lead. Spock advocate.


  • Daniel Dopierała

    Editor

    A Software Engineer who just likes to do his job well. Specializes in backend technologies on JVM, but does not shy away from frontend and big data.


  • Daniel Faderski

    Software engineer interested in distributed systems. Java & Python lover.


  • Dariusz Jędrzejczyk

    Likes to think of himself as a Platform Engineer. Leads the team responsible for Service Mesh, Service Discovery and libraries that boost developers’ productivity on the JVM.


  • Dariusz Wójtowicz

    JavaScript developer with several years of experience. Enthusiast of JS frameworks and modern web solutions.


  • Dariusz Zbyrad

    Senior Software Engineer in the Allegro Finance team. A programmer by profession, an electronics enthusiast by passion, with a knack for low-level programming.


  • Dawid Kubicki

    Software engineer and problem solver. I’m an ambitious dreamer and I smile a lot.


  • Dominika Pleśniak

    Robotic Process Automation Engineer at Allegro, responsible for developing and maintaining software robots. Enthusiast of learning new technologies. During winter season ski touring fan, during summer sailing addict.


  • Dorian Sarnowski

    Passionate software engineer with 7+ years of professional experience, specialized in creating scalable and high traffic web applications using new technologies. Enthusiast of clean code, automated testing and agile methodology. Personally passionate of rock’n’roll history, lyricist and bass player.


  • Edyta Kopczyńska

    Edyta is the Product Owner for Allegro search engine. She has been in product development for 10 years. She enjoys using agile methods, UX design and metrics to create products that customers love.


  • Eryk Napierała

    Guardian of web performance at Allegro. Front-end developer who is not afraid of data analysis. Meet.js Poznań co-organizer.


  • Ewa Bugajska

    Ewa is a software engineer with 6+ years of professional experience in Java technologies. She is a big fan of clean code. Believes that programming should be more promoted and we should encourage children to learn it, as it develops logical thinking. At Allegro, she works in a team which develops solutions for the financial department.


  • Ewelina Bednarz

    Ewelina is a data science intern at Allegro with a degree in mathematics and neuroinformatics. She is also passionate about quantum computing and biological signal processing.


  • Filip Błaszczyk

    Software engineer with functional programming inclinations. JVM enthusiast with special place in heart for Scala. After hours - wannabe devops and beatmaker.


  • Filip Marszelewski

    Software engineer and team leader at the team responsible for Allegro listing. Especially interested in chaos engineering and building resilient systems in microservices architecture using reactive and asynchronous patterns.


  • Grzegorz Dziadosz

    A software engineer interested in building resilient and scalable distributed systems. At Allegro, he works in a team which develops a Pay-per-Click (PPC) advertising system.


  • Grzegorz Kaczmarczyk

    Software developer and leader. In recent years working mostly on BigData projects. Fan of simplicity both in life and in software.


  • Grzegorz Witkowski

    Grzegorz is a software engineer with 5+ years of professional experience. He is interested in modern web frameworks and creating high quality code in Java using non-obtrusive design patterns. At Allegro, he works in a team which delivers solutions for the financial department.


  • Hubert Gęzikiewicz

    Software engineer who works mainly on backend services of various shapes and sizes. Likes to understand the bigger picture of how systems work and integrate.


  • Ireneusz Gawlik

    Fascinated with Machine Learning and applying it to create products at scale. When he wanted to develop and learn while working in the best commercial ML research group in the country, he created one. In his spare time he plays the drums, traveling with bandmates to unusual places.


  • Jacek Szczerbiński

    Jacek Szczerbiński obtained his PhD in Chemistry from ETH Zurich. He then fell in love with ML and became a Research Engineer at Allegro. Currently he is studying robustness of text classifiers against mislabeled training data. His superpower is explaining ML to non-technical people.


  • Jacek Żoch

    Jacek is a Solutions Architect and software engineer with almost 15 years of experience in Java-related technologies and more than 8 years experience in designing Web applications.


  • Jakub Demianowski

    Kuba works at Allegro crafting recommendation systems, leveraging microservices, big data, and MLOps. Outside of his technical explorations, he is an avid wall climbing enthusiast.


  • Jakub Dropia

    A software architecture enthusiast and problem solver in the .NET and distributed systems world with more than a decade experience. For over 3 years has been building the Allegro Pay Internal Developer Platform as Engineering Manager leading the team and providing technical vision.


  • Jakub Jedlikowski

    Front-end Software Engineer at Allegro


  • Jarosław Glegoła

    Front-end software person. Loves TypeScript so much that he uses it in real life.


  • Jarosław Grabowski

    Jarek works at Allegro Group building big data collecting and processing system. For over three years his daily job has been to implement and troubleshoot Pig, Hive and Cascading jobs run on one of the biggest Hadoop clusters in Poland.


  • Jerzy Jelinek

    Webperf Team member. Performance enthusiast. Short sentences lover.


  • Joanna Antkowiak

    At Allegro, Joanna works as an Event Specialist in PromoIT team.


  • Joanna Toboła

    Agile Coach with 3 years of professional experience, especially coaching and mentoring Mobile teams. Passionate about people’s behaviour and data visualisation. Follows the approach - you get what you focus on.


  • Jon Skeet

    Jon Skeet is a Staff Developer Relations Engineer at Google, currently working on the .NET Client Libraries for Google Cloud Platform. Jon is best known for his contributions to Stack Overflow, along with his previous Manning books including C# in Depth.


  • Julia Bluszcz

    Julia holds degrees in statistics and quantitative methods in economics from the Humboldt University in Berlin and Warsaw School of Economics. She has gathered work experience in tech start-ups Nethone and Omni:us where she worked on fraud detection in credit card transactions and organized tech-related events, e.g. Machine Intelligence Summit in Berlin. Her scientific interests include machine learning, data visualization, and econometrics. Julia works as a Senior Data Scientist at Allegro, where she specializes in forecasting and analysing consumer buying behavior.


  • Julian Szulc

    Site Reliability Engineer responsible for Allegro Platform. In Allegro Group since 2011. Software Engineer with over 10 years of experience in building and maintaining complex IT system using C++, Python, PHP and Ruby. OpenWRT and Raspberry Pi enthusiast and amateur photographer.


  • Justyna Osten-Sacken

    UX researcher part of a team taking care of end-to-end customer experience - starting from search and selection till purchase. Having her team by her side, she creates knowledge and recommendations based on customers opinions. It helps teams to introduce new products or changes to existing ones. She practices calligraphy, likes Italian small towns and micro trips around Poland. Cooking relaxes her very much. Hitchhiking enthusiast.


  • Kacper Koza

    Senior Software Engineer at Allegro.


  • Kacper Stodolak

    Front-end Software Engineer. Taking care of the Offer page at Allegro. In private sport and cooking enthusiast.


  • Kalina Kobus

    Senior Research Engineer in the Machine Learning Research team, working on NLP in the e-commerce domain. Kalina Kobus obtained her PhD in Machine Learning from Poznan University of Technology. Her research interests include large-scale text classification, deep metric learning and the robustness of classifiers against mislabeled training data.


  • Kamil Borzym

    Kamil is an iOS software developer. He is very curious of how things work internally, so he likes to decompile frameworks and apps.


  • Kamil Jędrzejuk

    I am a Software engineer and for over 8 years I have been interested in and follow topics related to Domain Driven Design, Event Storming and software design. Another area that interests me is the Java Virtual Machine and more and more often bare-metal programming.


  • Kamil Krysiak

    Front-end software engineer and enthusiast of new web technologies. So frugal that he built his own keyboard.


  • Kamil Piska

    Kamil is a software engineer with 5+ years of professional experience. He is interested in creating distributed, scalable and fault-tolerant web applications using software design patterns and clean code rules. At Allegro, he works in a team which develops solutions for the financial department.


  • Kamil Pyć

    Developing iOS apps for over a decade. At Allegro, he works in a core team which focus on making other engineers work easier.


  • Kamil Starczak

    Software engineer at Allegro Pay. .NET developer, cloud enthusiast, DevOps practitioner. Outside of work he is a cat owner and coffee lover who enjoys hiking and spending time in nature.


  • Kamila Rybkiewicz

    An enthusiast of agile teamwork and close collaboration. Her personal mission is to bridge the gap between Business and Technology in the area of Process Excellence and Process Automation.


  • Karol Grabowski

    Karol is a junior developer with less than two years of professional experience in Java technologies so far. At Allegro he works in a team responsible for migrating legacy Allegro listings to the SOA world. He belives that user is most important part of the whole service.


  • Karol Kuc

    Karol is a software craftsman and data analysis enthusiast. His main interests lie in cloud distributed systems but he also sets his first steps in frontend development and data modelling.


  • Kasia Wróbel

    UX designer who let her curiosity be the driving force of her life. Introverted, but willing to discuss dogs. A lifelong bookworm with a black sense of humour included.


  • Katarzyna Małecka

    Since 2008 I’ve worked as a project manager combining it with UX Design. I write articles for IT magazines and tales for children. Apart from that, I am an owner of a white British cat with an unbelievable level of fluffiness.


  • Katarzyna Zadurska

    Editor

    Frontend Engineer at Allegro Ads. React enthusiast with passion for good quality code and attention to detail. Genuinely excited about code review. Willing to learn and discover things, whether it is code-related or just a new spot with eclairs.


  • Kinga Krajewska

    Scrum Master with 4+ years of professional experience, passionate about Agile product development, team dynamics and its evolution and coaching. At Allegro since 2013, currently working with teams from Finance and Payment Departments.


  • Klaudia Nazarko

    Research Engineer in the Machine Learning Research team working on large-scale recommendation systems.


  • Klaudia Walewska-Łubian

    Data Scientist with 9 years of experience in applying statistical methods to socio-economic research, marketing, and e-commerce data. Worked in international policy research organizations (Coffey International, NatCen Social Research) and top FMCG companies (Procter&Gamble, Unilever). A year ago moved to Allegro to support its experimentation platform and predictive projects.


  • Konrad Kamiński

    Software developer who likes to have a broad picture of the things he’s using/working with. An old timer.


  • Krystian Szczucki

    Krystian has been an Analyst in Allegro Group for over 4 years. He is a follower of user-centered design and logical reasoning.


  • Krystyna Abraham-Walasiak

    Agile coach at Allegro, psychologist and experienced social skills trainer approved by Polish Psychologists` Association. She graduated from the School of Transactional Analysis and has participated in a 4-year programme of specialized training courses in the Organisational TA. While working in IT, she likes to look inside a team and analyse relationships between group members.


  • Krzysztof Cienkosz

    Project manager with an agile attitude that has been carrying out various IT projects in an international environment for over 8 years. Passionate about agile techniques and confronting plans versus reality. Enjoys challenges and meeting interesting people. Disapproves of unpunctuality. Father of two daughters and a soul windsurfer.


  • Krzysztof Debski

    Technical enthusiast, software engineer and product owner of Service Bootstrap developed in Allegro. He is open to all new technologies and programming languages and he has no fear to work on legacy systems and rewrite it in modern way.


  • Krzysztof Kocel

    Krzysztof works at Allegro Group since 2012. He is interested in mobile security and reducing data usage.


  • Krzysztof Kwiatkowski

    A software engineer with 7+ years of professional experience. A Node.js enthusiast. At Allegro, he works as a front-end webdeveloper.


  • Krzysztof Mikuta

    Frontend software engineer who does not run away from backend. Mostly interested in software architecture and biological modeling. Always ready to learn good patterns. Tech speaker, mentor and home barista.


  • Krzysztof Muzalewski

    Front-end enthusiast, HTML5/CSS3 and JavaScript passionate. He believes that esthetics and UX are as important as coding itself. A member of several teams developing portals for Allegro Group. At the moment he’s deeply involved into website optimization for desktop and mobile.


  • Krzysztof Przychodzki

    Software engineer. At Allegro I work in a team responsible for the Allegro Smart! loyalty programme. I am interested in EventStorming and I actively promote this technique at Allegro. I have set up an EventStorming Guild where we share knowledge and support - for example as session facilitators.


  • Krzysztof Wędrowicz

    Polyglot software engineer with a passion for problem solving. Loves combining soft and hard skills to improve processes, deliver quicker and better results. At Allegro responsible for API related things: performance, security, usability, integrations.


  • Łukasz Drumiński

    Łukasz is a Tech Lead who likes to understand how things work under the hood. He is a core developer of Hermes, a message broker in which low response times and high throughput are important requirements.


  • Łukasz Kuciński

    Łukasz is an Assistant Professor at the Polish Academy of Sciences. His research focuses on machine learning and he co-leads a reinforcement learning lab. He contributes to the growth of the Polish machine learning community, hosting the reinforcement learning seminar and co-organizing a deep reinforcement learning course.


  • Łukasz Mach

    Still surprised by the fact that sequences of words in a computer can do various things.


  • Łukasz Przybyła

    Łukasz is a Java developer with 4 years of professional experience. At Allegro Group since 2013. Currently a member of the team which works on API.


  • Łukasz Rokita

    Software Engineer working on Cloud and Big Data. Always on the lookout for simplicity and patterns to translate into architecture. Dedicated reader of all things software engineering and JVM enthusiast. Avid skier and table tennis player.


  • Łukasz Solniczek

    iOS Mobile Software Engineer. Works on MBox - the Server-driven UI tool.


  • Maciej Adamczak

    He’s been Product Owner for over 2 years, at Allegro Group for 7 years. After work he likes to spend his time at the shooting range, playing board games or online matches. Fan of Terry Pratchett, Monty Python and South Park.


  • Maciej Arciuch

    Maciek works at Allegro on developing a scalable, distributed data collection and analysis system. Former Java EE developer, now a Scala, Spark and functional programming enthusiast.


  • Maciej Mościcki

    Software Engineer at core Technical Platform team. Mainly interested in distributed systems, concurrency and Information Retrieval. Likes to open black boxes.


  • Maciej Piotrowski

    Maciej is a passionate iOS developer that pays much attention to details and code quality. He likes improving things, always looking for better solutions because he’s amazed that in programming world issues can be solved in 100s of ways.


  • Maciej Suszko

    A Senior Software Engineer at Allegro working on our internal Metrum Design System. An enthusiast of automation and innovation. Fueled by a passion for 3D modeling and tinkering with game engines.


  • Magdalena Mazur

    Frontend Software Engineer, loves to resolve problems. At Allegro working on an advertising tool - Allegro Ads, and all the adverts that you can see on the platform. ;-)


  • Małgorzata Karmazyn

    Małgorzata is a software engineer focused on backend microservices and big data. Code simplicity and unit testing enthusiast.


  • Marcin Borkowski

    Marcin Borkowski is an agile coaching enthusiast who believes that questions appear only because there are answers, and Scrum Master is a catalyst in the process of finding the right answers.


  • Marcin Konkel

    Marcin is an Agile Coach at Allegro Group, passionate about agile, coaching and travelling. He helps teams to be more agile by coaching and learning with them, removing impediments and cooperating with the organisation to foster change and improve working environment. He has experience working with mature and ‘new to agile’ teams. Formerly acting as a Project Manager and coordinating globally dispersed (USA, Europe, India, China) as well as local project teams in financial / IT environment. Personally an avid photographer travelling to distant and less distant places to capture moments that stole his attention — sharing his stories at marcinkonkel.com. Additionally, he’s writing and sharing his professional experience at medium.com/@m_konkel.


  • Marcin Kuthan

    Marcin is a Big Data engineer working at Allegro Group since 2014. He genuinely likes programming, problem solving and learning new trends in software methodologies, tools and languages.


  • Marcin Moskała

    The autor of Effective Kotlin and Android Development in Kotlin, the founder of the Kt. Academy and Learning Driven, programming trainer, speaker at international conferences, experienced developer.


  • Marcin Warczygłowa

    Marcin is a software engineer with 9+ years of professional experience mostly in PHP and technologies around JVM. He is interested in creating distributed, highly scalable and fault-tolerant web applications. He likes to try new technologies and programming languages. At Allegro, he works in a team responsible for purchasing process.


  • Marek Szkudelski

    Frontend Software Engineer in Allegro. Passionate about programming for most of his life. During breaks at work, he loves to listen to true crime podcasts and fantasy books. In spare time he spends time with his family.


  • Marek Walkowiak

    Just a simple software engineer, who values everlasting concepts over transient frameworks and technologies.


  • Mariusz Kopylec

    A Java developer passionate about source code architecture. Creator of open-source libraries and those used internally at Allegro.


  • Mariusz Strzelecki

    A software developer with 5+ years of professional experience. Now working as a Senior Data Engineer in Allegro Group, developing tools that support internal Big Data ecosystem and contributing to Open Source.


  • Mariusz Wojakowski

    Harnesser of JVM-ish languages in the service of business during the day, papers reader at night. Fan of distributed ‘everything’, FP novice.


  • Mariusz Wojtysiak

    Software developer at Allegro, currently exploring the knowledge of REST API management.


  • Martyna Niszczota

    Martyna works in Delivery Promise product. Her priorities are effective, client-oriented results; and maintaining positive relations within the developers team and promoting cooperation with other departments. Martyna has got an HR background and her view of the IT world is different from the standard one.


  • Mateusz ‘Serafin’ Gajewski

    Mateusz is a solutions architect responsible for financial and payments systems. His main areas of research interest are: scalable, distributed computing in cloud environments, reactive programming and failure resilience.


  • Mateusz Krzeszowiak

    Former editor

    Webperf Team member. Likes to constantly optimize and improve existing solutions. Finds it hard to stop talking about his work and sharing knowledge.


  • Mateusz Kuźmik

    I just like to know how things work. On a daily basis, I spend a lot of time with JVM Tech.


  • Mateusz Podlasin

    Mateusz is a frontend developer, dreaming about a career in machine learning. He used to be a humanities student, dreaming about a career in frontend development.


  • Mateusz Stolecki

    Senior Software Engineer at Allegro Pay. .NET developer, software and hardware enthusiast. Especially interested in performance optimization. Overclocker and PC builder in spare time.


  • Mateusz Sulima

    Mateusz has been working as a Scala developer at Allegro Group in a recommendation platform team for a year. Earlier he worked as Node.js, Java and Python developer. His interests focus on performance and consistency problems in distributed systems.


  • Michał Dulęba

    Michał is a software engineer with 11+ years of professional experience in testing software, working in Agile since 2014. He believes that QA role is much more than validation and bug chasing activity. At Allegro, he works in a team which develops solutions for the financial department.


  • Michał Jezierski

    Michał works as a webdeveloper since 2008. He speaks JavaScript, has strong Java background and loves new technologies around JS and HTML. In his free time he contributes to open source projects on GitHub.


  • Michał Karykowski

    A software developer with 8 years of professional experience. At Allegro Group since 2012. His family calls him a workaholic.


  • Michał Knasiecki

    Java/Kotlin/Scala software developer working at Allegro in automatic frauds prevention team.


  • Michał Kosmulski

    Editor in chief

    Michał is interested in all things high-performance, whether it be low-level stuff like analyzing how OS caches affect I/O operations or high-level like proper application design and functional programming. At Allegro, he has worked both as a software engineer and as a team leader, in finance and advertising divisions.


  • Michał Kowalcze

    Software engineer interested in products that people love. Feedback loops enthusiast. At Allegro, he works as a development team leader (Allegro Biznes).


  • Michał Kwiatek

    I’m a Junior Mobile Software Engineer at Allegro Pay who works with Android. I like creating perfect screen layouts and the best user experience. I’m a big fan of Formula 1.


  • Michał Lewandowski

    Michał is a Software Engineer passionate not only about reactive programming and failure resilience but also about how people and teams work together. Although he enjoys rewriting legacy systems to modern solutions, he loves working with fresh and well-crafted code.


  • Michal Nowostawski

    Change catalyst and agile enthusiast who takes care of development process in Allegro. As Scrum Master facilitates teams as well as collaborates with other agile coaches to make organisation better. Technical background helps him in better understanding of development mechanisms.


  • Michał Tydryszewski

    Michał is a senior software engineer with four years of professional experience. He believes that being pragmatic and thinking-while-doing is the key to every success.


  • Michał Zając

    Michał is a Ph.D. student at Jagiellonian University. He is interested in Machine Learning, Reinforcement Learning and Continual Learing. He is a former Research Engineer at Allegro. Michał also interned at Google Brain and Facebook.


  • Mirosław Gołda

    Former editor

    Mirosław is a software engineer with programming experience in Java, PHP, JavaScript and Node.js who joined Allegro Group in 2011. He likes playing around with various programming languages and technologies. Recently he’s experimenting with various automated testing tools and frameworks.


  • Olga Dudzik

    Product Manager at Allegro. Doing her best to show that Product Management is fun and that effective communication can work wonders.


  • Patrycja Husarska

    Senior Test Automation Engineer in Allegro Merchant Finance team, dedicated to finding bugs and ensuring quality. Avid traveler and gardener.


  • Patryk Bernacki

    Senior Software engineer at Allegro. Interested in how technology can solve real-world problems and improve the quality of life for people.


  • Patryk Krawaczyński

    Patryk is a Data Platform Engineer with 9+ years of experience in the web hosting & big data industry. Equally comfortable with both frontend and backend technologies. He likes to focus on solving problems and performance issues. In his free time NF.sec editor. At Allegro Group since 2011.


  • Paulina Sadowska

    I’m the team leader of the team working on MBox - the server-side rendering tool that allows developing features in native Android and iOS apps on the backend side. I enjoy reading, exercising, and sharing knowledge on my blog and Youtube channel


  • Paulina Szwed

    Software engineer at Allegro. Backend dev with strong interests in software architecture. Soft skills and cognitive sciences enthusiast.


  • Paweł Byszewski

    A software engineer passionate with mobile technologies, in particular interested in security. He believes that quality is key to long term success.


  • Paweł Czubachowski

    Software developer focused on continuous integration, deployment, clean code and code quality. He has sonar in his eyes and likes to do code reviews for other teams to learn something new or teach someone something new. In private he likes hard rock music, loud choppers and sport.


  • Paweł Grzeszczak

    A software engineer who spends most of his time working with frontend technologies. The rest of his time he devotes to inspiring others.


  • Paweł Lesiecki

    Paweł is a full-stack software engineer and an enthusiast of new technologies.


  • Paweł Leszczyński

    Paweł is interested in distributed databases stuff with a special focus on making Big Data easy. He is Product Owner in a Big Data Solutions Team at the Infrastructure department. The team develops and maintains a petabyte Hadoop cluster with endpoints like Apache Kafka messaging.


  • Paweł Piecyk

    Software engineer who spends most of his time working with JVM-related technologies. Groovy & devops enthusiast.


  • Paweł Rekowski

    Programmer and language agnostic. He thinks that you always have to select a tool that suits your needs. A Coach, Public Speaker, professional Networker and an enthusiast of The Thank You Economy. He believes in people and thinks it is better to give a man a fishing rod instead of fish.


  • Paweł Ustaborowicz

    Mobile passionate with over 10 years of experience on various positions within the mobile industry.


  • Paweł Wielądek

    Paweł works in Allegro as a front-end developer. Modern JavaScript enthusiast, especially ES6 and React. He believes that usability and reliability is as important as appearance and user experience.


  • Paweł Wolak

    Front-end developer who’s responsible for notifications in Allegro (sometimes also from the back-end side). Interested in topics related to web performance, usability and accessibility. After hours he likes getting lost in the woods practicing orienteering.


  • Paweł Zawistowski

    Paweł is a data scientist working at Allegro Group since 2014 with experience in industry and academia. He enjoys working with various types of data technologies and machine learning algorithms.


  • Paweł Zwierzchowski

    Software test engineer with a relevant full stack experience from various companies, who helps achieve better quality results by testing software and sharing knowledge. Testing has been his life since 2011. A real team member, involved not only in all the testing, but also in the final delivery of the product to end users. Besides testing, he loves all kinds of cars and PC games. A big fan of donuts.


  • Piotr Betkier

    Software Engineer who loves building useful tools and resilient systems. Works in one of the technical platform teams, where he’s responsible for common libraries and service discovery (Service Mesh). Conference speaker, host of Allegro Tech Podcast.


  • Piotr Ciemielewski

    At Allegro Group since 2009. Software Engineer with 5+ years of professional experience mostly in Java and PHP. He also used to work as a Scrum Master. Now leading development team delivering product informations for Allegro.


  • Piotr Gabryś

    I’m a Senior Data Scientist with over 10 years of experience in data analysis and modeling. I worked on main products at SambaTV, Growbots, and PAYBACK Polska. At Allegro I focus on predictive projects which help stakeholders make data-driven decisions.


  • Piotr Glazar

    Piotr is a software engineer interested in both concurrent and functional programming. He is a big fan of high-quality code and clean architecure. At Allegro, he works in a team which develops solutions for the financial department.


  • Piotr Góralczyk

    Software engineer who loves building reliable, scalable and maintainable applications. Would-be surfer.


  • Piotr Guzik

    Big Data engineer. My passion is all about creating useful software. In love with DDD and Druid.io


  • Piotr Kisielewicz

    Software engineer, sitting somewhere between numbers 41 and 43. I like tackling challenges at work and broadening my horizons by trying something new now and again. After work, I read books, play games (board games and tabletops too!), stream those games and bore my friends’ circle by talking about them non-stop.


  • Piotr Klimiec

    Software Engineer at Allegro.


  • Piotr Miłoś

    Piotr is a professor at the Polish Academy of Sciences and a visiting professor at the University of Oxford. He specializes in machine learning and co-leads a research group focusing on reinforcement learning. He actively works towards developing machine learning research in Poland, including hosting a reinforcement learning seminar, co-organizing a deep reinforcement learning course, and being a scientific advisor of the ML in PL association.


  • Piotr Orłowski

    Former blog founder

    Software Development Manager with over twenty years of experience in IT and e-commerce. At Allegro he manages the work of 150+ engineers taking care of their continuous substantive development, he is responsible for the technical quality, stability and efficiency of the Allegro platform. He likes simple solutions which gives more possibilities than originally planned :)


  • Piotr Płyś

    UX designer with an inclination towards simple yet lovable interfaces. Believes that a loyal user is the most cherished thing in the world to be found on the Web.


  • Piotr Prusiński

    I’m a Software engineer who likes to develop in every direction. I’m a fan of treating soft skills on par with hard skills.


  • Piotr Rżysko

    Piotr is a software engineer focused on building performant and resilient distributed systems. He works on a team delivering core parts of Allegro’s technical platform.


  • Piotr Stapp

    Doer. Microsoft MVP. Master of Science. Speaker and blogger. VP at devwarsztaty.pl. CxO of dotnetomaniak.pl. Don’t Stapp me now, please!


  • Piotr Szczepanik

    Software engineer with 15+ years experience in IT. Currently working as a Senior Software Engineer in Big Data team at Allegro. Passionate about automation and strongly typed functional languages.


  • Piotr Wikieł

    Piotr is a data platform engineer. He strongly believes in scientific attitude so he enjoys analytical part of his work the most. After hours he likes reading books with up to two characters and listening to some boring music.


  • Przemysław Dębek

    Przemek is a software engineer with ~3 years of experience in multiple technologies. He is interested in distributed, cloud-based architectures and NoSql databases. At Allegro, he works in a team which delivers solutions for the financial department.


  • Radosław Panuszewski

    Software engineer at Developer Experience Team. Gradle enthusiast and Kotlin fan who shares his knowledge internally and with the open source community.


  • Rafał Bryk

    Agile Coach with technological background. Passionate about creating good software in a proper way. Rafał works with people from Polish e-commerce and facilitates the process of making optimal decisions. Fan of modern technology, board games and cycling.


  • Rafał Głowiński

    Rafał is an experienced software developer who has spent most of his career working in Java and recently got very interested in Kotlin. His areas of interest include code quality assurance, highly scalable, cloud-oriented architectures and all aspects of system’s performance analysis.


  • Rafał Guźniczak

    A frontend developer. He deepens knowledge of web accessiblity since early 2019. At Allegro he mainly takes care of seller offer form and seller orders.


  • Rafał Mysłek

    Rafał is a software engineer with 10+ years of experience in Java/Spring technologies. He is an enthusiast of modern, lightweight (Microservices), distributed (Cloud), scalable (NoSQL) solutions. At Allegro, he leads a software development team delivering solutions for the financial department.


  • Rafal Staniszewski

    Rafal is a DBA with over 10 years of professional experience. With a team of 5 he is responsible for overall management, troubleshooting and performance tuning of Allegro’s critical 24/7 database systems. He specialises in Oracle and MongoDB databases.


  • Rafał Żukowski

    Rafał is an experienced software engineer with over 10 years in the field. In his work at Allegro he enjoys solving challenging problems, especially these related to algorithms and software design.


  • Riccardo Belluzzo

    Riccardo is a Research Engineer in the Allegro ML team and specializes in Natural Language Processing and Understanding. Riccardo is also a music freak, playing guitar in his free time and running a podcast about underground music and emerging artists.


  • Robert Mroczkowski

    Robert is a data platform engineer. He enjoys solving problems and learning new trends in Big Data. Believes in data driven products. He likes to play hockey and to roller skate.


  • Ryszard Targoński

    Ryszard is a test automation engineer with ~5 years of experience especially in WebDriver-based technologies. He is interested in test automation, performance testing and frontend technologies. At Allegro, he works since July 2014 in a team which delivers solutions for the finance sector.


  • Sławomir Bolimowski

    Sławek is a software engineer with 10 years experience. He is intrested in creating well designed and highly scalable web applications. At Allegro, he works in a team which develop solutions for the financial department.


  • Szymon Adach

    Software engineer who enjoys working with .NET and spends his free time tinkering with his hydroponic garden.


  • Szymon Jasiński

    Szymon is a clarinet player by education and a systems engineer by profession. At Allegro Group since 2013.


  • Szymon Marcinkiewicz

    Szymon is a Senior Software Engineer at Allegro working in the Technical Platform department. He is one of the team members responsible for Allegro’s messaging system and authorization server.


  • Szymon Tur

    Szymon is an iOS developer with several years of experience on this platform and web development background. Enthusiast of user friendly mobile applications and modern web solutions. At Allegro Szymon is a part of the team which is responsible for development of the iOS application for buyers.


  • Tetiana Khotiaintseva

    Software engineer in the monitoring team. Loves python, clean code, devops culture and challenging problems.


  • Tomasz Bartczak

    Tomasz is a software engineer who enjoys getting additional value from data in products he builds.


  • Tomasz Bocheński

    Tomasz is a Machine Learning Engineer focused on both research and building solutions that use state-of-the-art ML algorithms. MLOps fan interested in building scalable ML environments for fast and efficient experimentation.


  • Tomasz Fijałkowski

    Tomek graduated with a master’s degree in physics. He is a professional programmer by trade, and is a carpenter in his heart. He likes pretty girls, cold tequila and old school black metal.


  • Tomasz Gospodarczyk

    Former editor

    Frontend Engineer and team leader in the team responsible for offer page and navigation components at Allegro. Web Performance enthusiast and occasional music creator.


  • Tomasz Janiszewski

    Tomasz is a software engineer passionate about distributed systems. He believes in free and open source philosophy and occasionally contributes to projects on GitHub.


  • Tomasz Lelek

    Tomasz is a former Allegro engineer. He currently works at Datastax, building products around Cassandra, one of the world’s favourite distributed databases. Published author of “Software Mistakes and Tradeoffs: Making good programming decisions”


  • Tomasz Nurkiewicz

    Java Champion. Author, trainer, conference speaker, technical reviewer, runner. Wrote a book on RxJava for O’Reilly. Claims that code not tested automatically is not a feature but just a rumour.


  • Tomasz Richert

    Engineering Manager in Allegro Advertising division


  • Tomasz Szewczyk

    JVM software developer with interest in all kind of programming languages. Experienced in electronics, embedded C, Python, Java, Kotlin and JavaScript.


  • Tomasz Tarczyński

    Tomasz is a passionate, self-taught Software Engineer with a focus on JVM technologies, always looking to hone his engineering skills.


  • Tomasz Ziółkowski

    Engineering manager with emphasis on engineering. At Allegro I take care of a wide sort of reverse proxies that take off mundane work (like caching, or detecting malicious traffic) from our core services. I like to simplify things to such an extent that in many github projects, I am a leader when it comes to the number of deleted lines of code. Besides making source code more concise I like hunting … for performance bottlenecks.


  • Tymon Felski

    Tymon is a software developer who likes doing back-end stuff. He is highly skilled at applying screen protectors.


  • Volodymyr Khytskyi

    Senior Frontend Software Engineer with over 10 years in the field. Strives for software correctness and automation. A Rust enthusiast. At Allegro, he works in a team responsible for smooth operation of the home page, search, navigation and everything related.


  • Waldemar Panas

    Former editor

    Engineering manager with a rich background in professional software development. Since joining Allegro in 2018, Waldemar has been at the forefront of driving innovation and excellence in software engineering. His role extends beyond the confines of Allegro, actively engaging in the wider tech community as a co-organizer of the Java User Group in Poznan and GeeCON, a prominent conference focused on JVM technologies in Krakow and Prague.


  • Weronika Orczyk

    Junior software engineer and an enthusiast of new technologies who pays attention to details.


  • Wojciech Jurczyk

    Software engineer who likes breaking and fixing things. Open source contributor.


  • Wojciech Lesicki

    Team Leader in the IT Security department. Once responsible for cloud solutions (OpenStack, AWS etc.) and containerization (Mesos / Marathon). Currently, he focuses on defending the entire Allegro platform, the security of the implementation process, pentests and projects related to the security of the entire company. He works with developers and business looking for what can be done to make it more secure. He loves all possibilities of improving products / solutions / technologies. Recently, he also started promoting knowledge of IT security in native Poznań. In his free time he walks the mountains and explores the Att&ck MITER framework.


  • Wojciech Lizakowski

    QA/tester with several years of experience with various technologies (mobile, WWW, radio) and environments (Android, iOS, Windows, Symbian)


  • Wojciech Poniatowski

    Former editor

    As Product Team Manager Wojciech builds product teams and manages Product Managers within Allegro’s technology. At our Tech Blog he provides a bit of business perspective.


  • Yevgeniya Li

    Software engineer with interests in the world of Machine Learning and BigData. Full of enthusiasm and willing to help, open to new ideas and technologies.


  • Zbigniew Barczyk

    Also known as ZqBany. Code poet looking for beauty in everything he creates. Loves every problem that seems impossible to solve


  • Zbigniew Kuzera

    Backend software engineer, also recently not disgusted with frontend and mobile technologies. Enthusiast of inventing simple solutions.


  • Zbyszko Papierski

    JVM developer with 8 years of professional experience. He’s interested in topics related to search engines, cloud computing and parallel computing. At Allegro, he works as solutions architect, mostly in areas related to searching.