CodeteCON #KRK4 took place on 11 October 2018 in Krakow! Let’s move on to the autumn afternoon with technology on a large scale. Time for a conference report.

Even more technology fans and developers at CodeteCON #KRK4

We met with almost 300 developers and enthusiasts of modern technologies in Best Western Hotel Premier at Opolska 14a Street in Krakow. The edition put emphasis on topics related to Data Science, Backend and Frontend. We also had an open scene of lightning talks. The goal of the conference was to jointly explore the secrets of programming. We had over 20 lectures including discussions and networking. The 4th edition was different and more international than previous ones.

CodeteCON is remembered by many people as a conference that offers not only lectures but also workshops. This time we had the opportunity to co-organize workshops with Developer Circles from FacebookThe basics of distributed systems – build your own incident handling system! – That was the issue that participants moved and discussed.

The training was very unique because it was conducted by our special Keynote Speaker – Marek Denis who works as Production Engineer in Facebook.

The fact that the conference took place the same day as the Poland – Portugal match did not bother us at all. We took care of everything and prepared a specially designated football fan zone.

codetecon technology conference krakow


What were the tech talks about?

Now we can be proud that the level of each presentation was very high. It was confirmed by your grades and completed questionnaires, and by your comments and smiles after each talk.

We collected for you the best speakers not only from Poland. This time, we focused on foreign companies and their representatives. Interested who was speaking and which topic we discussed? Take a deep breath and read more below.

codetecon technology conference krakow

Focus on the Data Science

Well, no one is surprised by the fact that a lot is happening around Data Science in programming. That’s why the Main stage at CodeteCON #KRK4 was Data Science.

To warm up the Data Science Track the first speaker on the stage was Artur Suchwałko, Data Scientist & Owner at QuantUp with lecture What is important in real Data Science projects?

Artur talked about few Data Science projects and about their results, methods and conclusions: – detection of insurance compensation (Machine Learning) – prediction of customer leaving (Machine Learning) – predicting the registration of pre-paid customers in telecoms (with Deep Learning) – settlements with transport companies (classic and simple statistics). To sum up Artur structured all these with additional information to help do the Data Science projects better.

Christo Zonnev, VP Data Science & AI at Capgemini Invent was the 2nd speaker performing a lecture: Graph Technology – Why You Should Care And How To Apply It. As Christo said:

Graphs are all around us. Not just social networks heavily rely on graph theory and graph-related technology. Verticals like logistics, healthcare, human resources, finance, telecom, and hardware manufacturing among others combine data science algorithms and graph technologies for advanced analytics and decision solutions.

A presentation was an onsite-demo with bringing the graph concept to life and developing a recommender engine. Seemed like the topic was very interesting for the participants, because after the presentation many questions arose and Christo gave us a good overview of graph theory and the powerful concept behind it.

Next Data Science Speaker was Wassim El Hariri working as a International Project Manager at InSystems Automation GmbH. Wassim explored the issue: Production of the future. Autonomous intralogistics. Wassim invented SASHA robot “Smart Autonomous System for Hospital Assistance”. Starting from proANT platform, it is a fully autonomous mobile robot that automate food distribution in hospitals giving each patient the correct meal on time automatically. Recently InSystems Automation also launched the industrial version of market-ready SASHA. And this was the topic of Wassim presentation. The company does research on methods and basics for collaborating, learning and connected robot systems that can be implemented even in challenging dynamic-unsecure contexts. It was a pity that Wassim couldn’t take a robot with him! But who knows, maybe next time?

Beyond Web Interfaces was the next presentation performed by Fabrizio Ciacchi, Team Lead at Spryker Systems GmbH. Fabrizio told us a lot about bots and chatbots. His talk illustrated how to start building your own chatbot for Facebook or Alexa and by doing so, how we would have to structure our project, design our application and build a set of API. It was a very inspiring lecture, Fabrizio made a special video with his presentation, so if you’re interested you can watch it here.

Time for our Keynote Speaker! One before last on the scene was our special guest, Marek Denis, working as a Production Engineer in Facebook. His presentation Measure your systems to understand them attracted a big publicity and fame!

Software running in production environment is often like a black box for us. Yet, all systems need a way to be understood, fixed and improved.

In his talk Marek shared with us good practices and his philosophy on monitoring at scale, setting measurable goals and avoiding the worst – users reporting you have a system outage. Many thanks to Marek for such an interesting, meritorious presentation and the performance!

Last on the Data Science stage was Amadeus Tunis, Senior Manager at Deloitte. Amadeus gave a speech about Analytics & Cloud Platforms – industry use cases, trends & best practices. He precisely presented to us an industry-specific use cases for Analytics and Big Data in the cloud, discussed lessons learned and gave us an outlook on what lies ahead, for clients aiming to digitize their business as well as engineers making it happen. Amadeus, thank you for this insightful and professional talk!

Once we get tarry a bit, now let’s move on to the next, equally interesting part, especially for Frontend Developers.

codetecon tech conference fabrizio ciacchi spryker systems

Frontend on the viewfinder

First on the stage was Paweł Konior, a Trainer at Sages and also a Senior Frontend Developer at HSBC. Paweł made a live presentation and gave the answer to a question: How does modern Javascript work? As Paweł said:

Javascript engine, scopes functionality, runtime compilation, call stack, event loop, callback queue, job queue, RHS, LHS, host functionality, huh, a lot. So out of the box, Javascript gives you numerous functionalities. If you have the right way, your code will be better, it can show intention in a good way and your teammates will love you. Closures, promises, generators and many more will be easier for you after this presentation!

We were really happy to have this live presentation with real use-cases.

Second on the stage was Miłosz Piechocki, experienced Senior Frontend Developer, working at Sumo Logic. Miłosz introduced us to functional programming with his lecture: Learn functional programming in JavaScript and become a better developer! Let’s find out more from his abstract:

Functional programming conquers the world of JavaScript! Modern frameworks, such as React or Angular, draw their full attention from this fascinating programming paradigm. What’s more, more and more people treat some functional code-writing techniques as good practices.(…)

Thanks to this lecture we gained a deeper understanding of functional programming, which definitely became easier for us to navigate through JavaScript libraries and frameworks. If you want to become a better developer and create a readable and easy to maintain, free of bugs code you should definitely watch this presentation! Practical aspects of functional programming with the examples inspired by real situations – a pill of knowledge and practice, thank you Miłosz for this talk!

Now it’s time for a representative of Codete. Ladies and gentlemen, here’s a lecture performed by our Javascript Developer, Jakub Pietras. As Jakub said, on the market of modern web applications, achieving success requires creating an application with character – infatuation of the client and creating a unique climate. In his presentation Kuba told us how to use a common and at the same time an understated tool like SVG to create unusual and interesting visual elements. Participants learned some ways to draw complicated shapes and animations, not tearing out hair while supporting IE. It was really a great presentation with lots of positive reviews! We are happy that our talented Developer received such high marks in the survey.

Mateusz Konieczny, OpenStreetMap Contributor was the next Frontend speaker. A presentation was on why non-existent railway tracks and unpaved roads are a challenge for a style of map used around the world. Mateusz presented examples of problems and possibilities to solve them. Most of the materials were based on experience related to working on the style of the map, which is a default style at and is widely used by many who use OpenStreetMap data. Mateusz presented this talk in an interesting way, after the presentation we had a hot networking, and at the end….

Occured on the stage Vladimir Dejanovic, Leader & Founder of AmsterdamJUG, IT Manager at ING with the presentation: What Users Want, A/B testing explained. Here are a few words about Vladimirs presentation:

We all would like to know what users want, right? Then we could build it and get a lot of money for it. But how to find out without being psychic, can we ask them? The worst thing you can do is build the wrong thing. But how to know what is right and what is wrong? We don’t have a crystal ball. Is our gut feeling the best we can do?

Vladimir took us to the trip behind the scene of some of the most successful websites in the world and shared their secret with us: how they made it happen, how they decide what to build, when to build and how to make sure that it is what the users want. And of course how they made their fortune in the process of doing so. Vladimir was the last one who performed on the Frontend scene. Thanks a lot for this deep lecture!

Precious Backend Track

We cannot forget about the precious one, with tons of knowledge and real use-cases, Backend Track.

The Slower the Stronger: A story of Password Hash Migration was the first presentation performed by Tomasz Borowiec, a Senior Software Engineer at Ocado Technology. This talk was a case study of a successful migration of customer password hashes. Tomasz showed us what was problematic, what went wrong and how they dealt with it. Tomek also discussed the topic about slow hashing algorithms – such as Argon2, PBKDF2, BCrypt or SCrypt – and compared them to other popular hashing algorithms – like MD5 or SHA1. He told us a story of hashes which took about 80 ms to compute – not slow enough, fairly easy to crack. Thanks Tom for such an advanced level and very insightful lecture!

Next on the stage was Maciej Rybaniec with his speech about Real Time GraphQL. Maciej works as a Principal Software Developer at Grand Parade Poland. In the presentation Maciek showed us GraphQL’s capabilities in the context of push-based communication using the tools provided by Apollo organizations. During this engaging lecture we had an opportunity to see how to create easily a GraphQL server that allows subscriptions for events and use it in a simple client application.

Next representative of our company has appeared on the Backend track. Talented Mateusz Bryła works at Codete as a Senior Software Engineer. You could read the development and continuation of his presentation in the previous post. Mateusz gave a talk titled: Uncommon but handy: mutation testing / contract testing.

Most of the teams protect their products with integration tests. You also often use functional tests, manual regression, visual testing and others. But you can rarely see two concepts that are not quite so new and hip but still helpful and powerful – mutation and contract tests.

Mateusz clearly showed us how mutation and contract tests work, why and when should we use them, along with some background information and practical examples. A performance was with a lot of knowledge and full of positive energy, thank you Mateusz!

mateusz bryla codete at codetecon technology conference krakow

Adrian Stachurski, DevOps Engineer from Alten Polska, was the next speaker. Adrian’s goal of lecture Modern software developer was to draw a very interesting picture of who modern software developer is as a role.

In society but also amongst us IT professionals – there is much of cognitive bias and misunderstanding of what constitutes a successful software developer. What skills and what psychological attributes people working in software development should possess? Being able to solve logical puzzles? To design systems and interactions across business processes? Being able to test and point to security issues? If the modern software developer is to really be a “man of renaissance” – he can’t be very good at everything nor his specialization can be particularly deep in all areas at once. It’s just not possible. In medicine – we have general practitioners as well as many narrow specialties dealing with particular organs or systems.

Adrian very precisely showed us many analogies and helped to understand how we should think of role of software developer in XXI century. Many thanks to Alten Polska for supporting our conference with the special partner guest, Adrian!

The last two lectures were performed by Sebastian Schleicher and Tobias Balling from Blinkist. Blinkist was founded in 2012 and now connects 6-million readers worldwide to the biggest ideas from bestselling nonfiction via 15-minute audio and text.

Sebastian Schleicher, Director of Engineering performed a lecture about Stream-Based Mobile and Web Event Tracking backed by AWS Kinesis. This was about how Blinkist went from a very distributed, silo-like user behavior tracking to a centralized and stream-based solution that allows us to enrich and route events in real-time to any destination we want. By orchestrating several very affordable AWS services, this fully-managed solution provides a high level of availability and scales into eternity. Their Realtime-ELT pipeline framework Alchemist is published under the MIT license and can be adopted by everyone for free.

Tobias Balling, CTO of Blinkist in some way continued a speech by his own presentation Kicking off a Tech Product as the Only Tech Person. Tobias told us that building a software product and building software product are different things depending on the number of developers assigned to the project, the purpose of the project, the state of the company, market trends and the financial circumstances of the company. Within the last 6 years since Blinkist started the methodologies, the ways to write software have been reshaped dramatically several times. All phases of the company and the engineering methods have been focused on the goal to be achieved. This talk explained us the different phases of the Blinkist company, methodologies chosen, foul-ups made and lessons learned to provide young potential entrepreneurs an insight in kicking off projects as tech co-founders. This was very inspiring!

And for the end… Lightning Talks!

At CodeteCON conference we offer for the participants an open scene of lightning talks. This edition was made of 3 shorts talks and first was Kuba Birecki, Javascript Engineer, working in Automattic. Kuba talked about The art of (over)communication. As he said in his talk, working with distributed teams can be difficult and when it is, it usually boils down to communication issues. Kuba shared with us a number of basic tools and techniques that he and his coworkers use to keep the information flowing at Automattic. Thanks for tips, Kuba!

We also hosted on the stage CTO & Founder of KISS Digital, Adam Kubiczek. His lightning talks lasted 10 minutes advocating GIT, which did not necessarily make us git masters… 🙂 Adam asked:

GIT is not your primary tool? Come and see what you are missing. Do you use GIT, but would you like to learn something new? Come and you’ll probably see something you have not used before. Do you think you know everything about GIT? Maybe, but it’s worth coming and seeing it anyway.

What do you think about this talk? We think it was worth to see!

Last speaker was Andrzej Dobrucki, Founder at Timeqube. Andrzej presented us a short talk, very important for many of us who work in a bigger company: How to run productive meetings. Andrzej discussed why and whether we do need meetings, what is Timebox and how to set meeting goals. It was a very productive talk! 🙂

codetecon technology conference in krakow

Who was supporting CodeteCON?

Obviously, we cannot forget about our collaborators and friends. We would like to thank our partners with all our hearts for supporting CodeteCON conference. This edition we had a pleasure to host 11 partners: JustJoinIT, Magiczny Kraków, JustGeekIT, 4programmers, SIBB, ITKrk, Challenge Rocket, Women in Technology, WSEI Szkoła Programowania, NoFluffJobs and Alten Polska.

Special thanks to our great photographer Dawid Makowski and Piotr Wyszyński who were responsible for making a very nice recap movie that you will have the opportunity to see soon on our Facebook! Don’t forget to follow us!

We’re counting the days to the next CodeteCON!

It’s few months to the next edition in Krakow, but we’ve already miss you and we’re getting prepared for another CodeteCON in Lublin! which will be held next spring in Lublin. Stay tuned!

codete at codetecon technology conference in krakow


Marketing Manager interested in modern technologies, e-commerce and fashion. Trend Researcher.