Surprisingly, this is the first time we share with you a report from Allegro Tech Meeting (ATM) — even though it’s already the 12th edition of this special event.

ATM is a tech festival by IT for IT. Every year each Allegro employee looks forward to it based on the opinions of colleagues and the history of this meeting.

The very simple reason we decided to organize such an event is the fact that from a small IT team we’ve grown to nearly 800 technologists at Allegro and that’s too many to even say hi to everyone during normal work time.

ATM is the place where we can meet each other, share our experiences and just get to know — what’s up!

Join us in the fascinating journey through the inspiring, exciting and unique stories of Allegro technologists that we gathered to listen to in the first days of this fall.


The 12th ATM edition was the biggest one so far — there were over 500 technologists from all of our offices scattered around Poland.

The gloomy weather of the beginning of fall perfectly fit our decorations’ main theme — Blade Runner.

We had 2 days of presentations, including 10 big presentations, 12 lightning talks and a 7-hour party, that is 1380 minutes altogether that we spent on discussions about the future, tech news and simply drinking beer and having fun at the after-party.

Allegro Tech Heroes — special nominations

ATM is going up a level every year and there are also some changes that make this event more epic. This year there were special nominations for those of our colleagues who had significantly influenced how we work, how we change and operate better and smarter as the Technology team. People who use their knowledge and experience to change all of Allegro and whose attitudes and behaviors are worth imitating.

What makes it even more special — nominations and the final vote were in the hands of our IT employees. Congrats to all 10 Heroes who were chosen!

allegro tech heroes


Below you will find a short description of the main part of ATM, namely, presentations! It would be impossible to squeeze 2 days of presentations into one article, so we selected a few that cover various cultural aspects of our organisation.

Please note that all presentations are in Polish.

Machine learning

ML for you…

Have you ever wondered what the creation and development process based on machine learning looks like? Isn’t it just enough to use existing algorithms/libraries, put it all together and call it a day? During ATM we could listen to case studies of various projects whose goals are so complicated that you can’t achieve any meaningful results with just relatively simple statistics or rule-based systems. ‘A human option’ is not an option (sic!) because there is too much data and gluing existing machine learning blocks together is no longer enough: you need to check what the current state of the art looks like, apply it to your data, make corrections and ensure it behaves properly on production data.

But the problem complexity shouldn’t stop us from trying to solve it! I can’t imagine describing e.g. fashion clothes with attributes that will be clearly understood by both machine and people and filtering them in order to find the same shirt/dress. Taking into account the number of available offers on Allegro and UX we want to provide to our customers, the introduction of a visual search becomes a necessity!

After encountering such problems and various use cases, you can see that a research team in a technology company, which wants to set trends, is a must.

…and ML for me!

Culture at Allegro (and the vast amount of data) encourages you to experiment with machine learning by yourself. Adam Dudczak’s talk, with a clickbait title ‘The only presentation about ML you need’, was a great example of this. Adam led us through his experience gathered during bot creation for a ’Space Invaders’ clone simultaneously explaining basic concepts of machine learning, starting from data representation, model evaluation, underfitting/overfitting problem and ending with convolutional networks and deep reinforcement learning. The talk contains good practice quotes and also plot twists so if you want to feel bamboozled as well, check the video below :)

Technical — engineers by choice

The standard deviation of answers to the question ‘how did you like the presentation?’ is often very large for very specialised talks. As we know — it is hard to suit everyone’s tastes, but it is much easier to do so by talking about things used in everyday work.

Who wouldn’t want to know more about the cluster that his application is running on, a new communication layer in our microservice setup or deep JVM details? Paweł Jurczenko chose the latter subject and did a thorough overview of many topics related to threads on JVM. He talked about threading models, compared some concurrency primitives, explained challenges with non-blocking I/O and how to tune your application thread pools.

Of course we’re open to other topics — not strictly related to our day-to-day work: if you want to hear about some esoteric language or science stuff you definitely can! For example Krzysztof Szłapiński decided to tell us something about teleportation. But not like just normal teleportation: quantum teleportation. We were really interested in how it works, how we can use it and what the potential problems and limitations are. If you want to build yourself a teleporter, check Krzysiek’s presentation.


ATM stands for Allegro Tech Meeting, but man does not live by technological things alone. We want to share knowledge about non-technical topics as well.

Systems thinking — is structure the key?

Have you ever wondered how much interrelationships influence particular patterns of your behaviours? Have you experienced silent days, misunderstandings or disappointments when verifying the results of work in your teams? To find out what the real problem of those symptoms are and to support deep change in cooperation, Iza Goździeniak, Lean & Lead Agile Coach at Allegro — recommends to focus on the structure. Without the awareness that we operate in structures and systems, it is very hard to change anything. Iza talked about the systems thinking in examples and the methods to see something more than only the tip of the iceberg.

If you want to deep dive into particular cases - watch the video.

Deep working — is that a fairy tale?

Context switches are computationally intensive for computers. We can say that for humans they are even more problematic. So it’s probably best for us to minimise them, right? Darek Jędrzejczyk and Ireneusz Gawlik had a presentation about work organisation challenges, how to restore our ability of being ‘in the flow’ and whether deep working is possible at all. The talk titled ‘Let me code’ made us think if and how technology affects us in our everyday job and whether we use the available tools, like instant messaging platform in a good way. Unfortunately, we can’t share this presentation with you because it contains confidential information about our internal infrastructure. However, you can watch a cover of the song Let it go which illustrates what obstacles developers might be facing. Let us know what you think about this work style!



ATM is a kind of technology celebration at Allegro. These are 2 days filled with lectures on various technological topics. Every employee can participate or give a presentation (provided it convinces others with its abstract, of course!). At a company of this size, ATM is one of the few opportunities to meet all the people we work with (or plan to cooperate) in one place.

During a normal non-ATM day we have a lot of duties and meetings, so additional conversations with other teams are an addition rather than the main activity. However, we believe that we are able to achieve more as a whole and we try to spread the knowledge during ATM not only through speakers, but also organically — by participants. From our own experience, we can confirm that less busy engineers willingly join technical discussions (indeed, even more willingly!), which leads to cool conversations and interesting ideas!

What’s next

If you want to continue this adventure by yourself — take a look on our FB profile — where you can find all the videos from the conference.