meet.js Summit

// Katowice, Poland

Annual conference of the biggest JavaScript community in Poland. The meet.js Summit is an annual conference of the largest thriving JavaScript communities in Poland. An event that gathers over 500 web development professionals, front-end and back-end software engineers interested in modern JavaScript ecosystem and web technologies. This year we are meeting for the 7th time.


International Conference Centre in Katowice

Plac Sławika i Antalla 1, 40-163 Katowice, Poland


Friendly community


Our event unites a friendly and supportive community of web development enthusiasts.

Best location


Our venue is easy-to-reach for everyone. It is located in the city center, just a 15 minute walk from the main train station.

Tasty lunch

Lunch & Coffee

Enjoy the best coffee, snacks and delicious lunch.


Sunday, 29th September, 2019


Introduction to Next.js apps on ZEIT Now

University of Silesia, Kazimierz Lepszy Hall, 12 Bankowa Street
Workshop by ZEIT

During the workshop we will introduce the participants to Next.js by going through the steps to build a website that handles contact form submissions and sends them to you in a Slack channel. We will also explain how external services like Slack or Pusher can be leveraged using Now and Next.js, and walk you through the process to deploy these applications on the ZEIT platform Now.
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Monday, 30th September, 2019

  • Breakfast & Conference Registration

    Main hall

    We'll be set up next to the entrance so that you can check-in for the conference. Have your ticket ready and follow our staff instructions, so everything goes smoothly. After you pick your badge, enjoy some fine refreshments and appetizers. Meet old friends, make new friends, visit our sponsor booths or make yourself familiar with the venue.

    Remember to use the entrance to the International Congress Centre from Sławik and Antall Square, next to the Spodek Arena.

  • Event opening


    Kick off the conference with us as we go over the conference schedule, our Code of Conduct, formally introduce our staff, and our MCs!

  • Session I


  • The journey of converting ZEIT's blog from MDX to a Notion backed blog

    JJ Kasper

    At ZEIT we started our blog with a markdown approach which then evolved to MDX. While this approach has many benefits we noticed some drawbacks and set out to solve this by creating a Notion backed blog without losing the flexibility MDX gave us.

  • Modern Monorepo with Lerna

    Michał Jach

    Have you ever struggled with maintaining multiple, dependant repositories? Are you tired of npm linking nad building dependencies all over again? Organize your codebase with monorepo approach and never struggle again! With Lerna you can save tremendous amount of time and nerves. HMR works! Make your codebase way easier to maintain and speed your development process using Monorepo approach just like Facebook, Twitter or Google.

  • A Day in the Life of a Remote Developer

    Patryk Pawłowski

    Work from exotic beach, sipping Margaritas all day long, surrounded by like-minded digital nomads… Isn't it idyllic? It indeed is. Life of a remote developer is far away from the picture painted by media. Let me share with you my experiences & lessons learned during 6 years of working remotely. Why myths are just myths and don’t work in real life? How to stay productive when working remotely? How to manage expectations, loneliness and stress when no colleagues are around?

  • Coffee break

    Main hall

    Meet old friends, make new friends, visit sponsor booths, enjoy some fine refreshments and snacks, or rest a bit in our chillout zone!

  • Session II


  • Beyond ES6 - new possibilities of JS and how to use them

    Sylwia Laskowska

    The ES6 standard is already widely used. However, the pace of JavaScript development does not slow down! I will present the most interesting elements of newer EcmaScript standards. Which can help us in our daily work? How to use them?

  • How a test runner works?

    Michał Pierzchała

    We're using test runners like Jest daily (or I do hope so!). They boost our confidence by running JS efficiently in various environments. But what's going on under the hood? How do they make it fast? How can they run only what's relevant to your changes? We'll explore the design behind Jest and how its flexibility allows running e.g. Python alongside TypeScript is a single run. Prepare for a deep dive into what makes for a high performance, well designed test runner based on Jest, which I have a few years of experience with.

  • Real User Measurements revisited

    Rafał Rumanek

    How far can we go without knowing how our web apps *exactly* perform? In frontend development we tend not to worry about measuring performance and postpone fixing issues - and it's perfectly fine as there are so many other areas you might rather want invest your budget into. Nonetheless, once your project becomes bigger and you face complaining clients, performance problems can no longer be neglected. With the help of Real User Measurments you can not only learn what your real users experience but also understand how that happens. In this walk we will dive into the world of poor performing apps we create, discover some most useful APIs that allow you to analyze it on a client's end, and question how to tackle the problem of measuring the right things from a practical standpoint.

  • Lunch break

    Dining space (follow the signs)

  • Session III


  • Don't be afraid to fail. Be prepared for it. A brief story of a commit getting into production and back

    Bartosz Gryta

    The story about Jira’s frontend delivery process: a pull request is only the beginning. Dev-ops-ish talk from the frontend developer’s point of view about CI/CD, production incidents, hotfix processes, rollback and rollforward — things you should know before you need them.

  • Who needs Same-Origin Policy?

    Kacper Pietrzak

    The World Wide Web exists now for 30 years. The Web is designed to be backwards compatible, and is now capable of things that people didn't even dream of in 1989. That leaves us with a huge amount of rules that are not clear to someone who didn't have a chance to understand how Web changed over the years. One such rule or set of rules is Same-Origin Policy. This policy significantly impacts everyday work of Web developers but unfortunately is often misunderstood. It is even more important in the context of popular attacks such as CSRF. In my talk I'll explain some intricacies of Same-Origin Policy, show some live attacks and will teach you how to mitigate them.

  • A developer's take on security

    Zbyszek Tenerowicz

    Discover tools and practices that give you most security benefits for the least time and effort investment. Secure your node.js app, prevent XSS attacks, build the tools and culture of taking care of your dependencies' security. It features the solution to running npm audit as part of CI process and not regretting it. Yarn support too!

  • Coffee break

    Main hall

    Meet old friends, make new friends, visit sponsor booths, enjoy some fine refreshments and snacks, or rest a bit in our chillout zone!

  • Session IV


  • Hype Driven Development sucks

    Jacek Tomaszewski

    2012: Let's do everything in Angular!
    2017: Let's rewrite all APIs to GraphQL!
    2018: Let's store everything in React Contexts!
    2019: React hooks everything!
    2019.5: Svelte!

    ... and whenever I want to stand up and just mention "Uhm, no. Not everywhere.", people are looking at me like I was the dumbest person in the room.

    By this talk, I want to:
    - mention a few hypes in front-end that we had in the recent years,
    - observe that in other programming languages people don't change their frameworks with every year,
    - note that you should always be able to say WHY "X everywhere!" is the way to go,
    - mention a few real examples from my past, when product owner or other developers wanted to push for a solution without thinking about the problems of the code or product first,
    - conclude that we should always be mature while making decisions. Always think about the problem first, and only then about the solution. Never do the other way around.

  • Native, hybrid, PWA? 🤷‍How to deal with it?

    Marta Wiśniewska

    Today the web is powerful. If you are a web developer, you have a power... to create wonderful things. In this talk, I will present how to use it to create an amazing native experience. In times where a lack of technologies is not a problem but the selection process it is, I will compare different technologies on mobile (native, hybrid, PWA) and will give you a cheat sheet how to find a perfect solution for your app and its requirements. We will focus on UX (User Experience) as well as on DX (Developer Experience). In this talk, I will present fundamentals about different technology solutions on mobile. I want to convince the audience that they don't need superpower (and skills to develop native apps) to create an amazing native experience. I will show a primary aspect you should focus on before choosing technology stack for your product.

  • Progressive Web Apps in Practice

    Łukasz Romanowicz

    I will cover most of the features available for PWA developers today along with common use cases and patterns. It’s a kind of is a deep introduction to PWA combined with lessons learned from using it for a different business requirements and goals.

  • Event closing


    Don't run off yet! Together with our sponsors, we will announce winners of all these great competitions that you participated during the breaks. There'll be also a chance to win a ticket for WE-CAN'T-DISCLOSE-A-NAME-BUT-ITS-A-BIG-EVENT conference that takes place in October!


  • Photo of speaker: Marta Wiśniewska

    Marta Wiśniewska


    Marta is a Frontend Developer, co-creator of PWA Fire, enthusiast of Angular, PWA, hybrid apps who loves exploring new web features and following hottest trends in tech. Sport and coffee - things she can't live without and the reasons why she approaches all experiences with excitement and energy.

  • Photo of speaker: Michał Pierzchała

    Michał Pierzchała


    UI engineer at Callstack. Passionate about building mobile and web experiences, high quality JS tooling and Open Source. Core Jest & React Native Community contributor. Space exploration enthusiast.

  • Photo of speaker: Bartosz Gryta

    Bartosz Gryta


    Software developer experienced in creating and maintaining a world-class product used by millions of customers everyday. Specialised in web development and front-end technologies like React, Redux and flow-type. A product-oriented team-player who walks in other developers’ shoes and wears a customer’s hat.

  • Photo of speaker: Michał Jach

    Michał Jach


    Senior Frontend Developer at IG

  • Photo of speaker: JJ Kasper

    JJ Kasper


    Software Engineer at ZEIT on Next.js core team. He's passionate about building great development and user experiences by leveraging open-source technology. He enjoy getting to learn about the latest developments in tech and finding ways to apply these developments throughout my work.

  • Photo of speaker: Sarup Banskota

    Sarup Banskota


    ZEIT team. Obsessed about developer experience and open source tech.

  • Photo of speaker: Sylwia Laskowska

    Sylwia Laskowska

    In my work I mainly deal with front-end technologies. I love JavaScript for its dynamic development and the almost unlimited possibilities it gives us. I am willing to use technological novelties at work if they are fit for it.

  • Photo of speaker: Patryk Pawłowski

    Patryk Pawłowski

    I am a seasoned full-stack developer who specializes in modern JavaScript - from architecting back-end and APIs to building pixel-perfect web and mobile apps. Thanks to experience running my own company and having background in design, I am a great facilitator between business and product teams. When I am away from keyboard, you can find me backpacking, ski-touring or kitesurfing. I also enjoy speaking at conferences.

  • Photo of speaker: Kacper Pietrzak

    Kacper Pietrzak


    Fullstack JavaScript and Blockchain Developer, Cofounder of Nebula Network. Passionate about Web Security and developing solutions for a better world. Likes to express his creativeness on a variety of game jams. Interested in Eastern Philosophy, non-conformist and free-minded approach to life.

  • Photo of speaker: Łukasz Romanowicz

    Łukasz Romanowicz


    Full-Stack Developer working in IT for over 8 years. Open-Source contributor. Big enthusiast of Unit Tests, Automation, IoT, and U.S. Motorcraft. Every day explores vast expanses of libraries, frameworks and programming languages in pursuit of higher quality code and architecture. Currently working as Vue Storefront Core Developer & Team Leader at Divante.

  • Photo of speaker: Jacek Tomaszewski

    Jacek Tomaszewski


    Web Developer since being a 10-year old kid. Freelanced for about eight years and worked in software companies for another two. Constantly learning new stuff on back-end and front-end. (Haven't picked his side yet.) Currently big fan of typed languages (like TypeScript), functional programming and well structured code. Prefers calling coding work as "engineering", rather than "art". Occasionally writes blog articles.

  • Photo of speaker: Zbyszek Tenerowicz

    Zbyszek Tenerowicz


    Full-stack developer and technology researcher. Running over 30 Node.js powered applications in production at Egnyte Inc. Open-source enthusiast. Teaches advanced JS for front-end and back-end. One of the oldest members of Meet.js Poland community - both as a speaker and organizer. Most recently, a father.

  • Photo of speaker: Rafał Rumanek

    Rafał Rumanek


    Business-driven engineer with deep passion for frontend development, especially topics related to web performance and AdTech industry working at Codewise, Krakow. Event organizer & host of Angular Dragons meetups. Impatient user of the web. Golden retrievers lover.

  • Photo of Master of ceremonies: Bartłomiej Michalski

    Master of ceremonies

    Bartłomiej Michalski

    Speaker, mentor, event organizer and podcaster. Focused on sharing knowledge, teaching good practices and creating value. Co-creator of and DostarczajWartość.pl. Co-organizer of WUD Silesia and Gliwice Software BarCamp.


All conference tickets are now sold out.


The primary goal of meet.js Summit 2019 is to be inclusive to the largest number of contributors, with the most varied and diverse backgrounds possible. As such, we are committed to providing a friendly, safe and welcoming environment for all, regardless of gender, sexual orientation, ability, ethnicity, socioeconomic status and religion (or lack thereof).

We invite all those who participate in our events to help us create safe and positive experiences for everyone.

Unacceptable Behavior

Unacceptable behaviors include: intimidating, harassing, abusive, discriminatory, derogatory or demeaning speech or actions, harmful or prejudicial verbal or written comments related to gender, sexual orientation, race, religion, disability; inappropriate use of nudity and/or sexual images (including presentation slides); inappropriate depictions of violence (including presentation slides); deliberate intimidation, stalking or following; harassing photography or recording; sustained disruption of talks or other events; inappropriate physical contact, and unwelcome sexual attention.

Consequences of Unacceptable Behavior

Unacceptable behavior from any community member, including sponsors and those with decision-making authority, will not be tolerated. Anyone asked to stop unacceptable behavior is expected to comply immediately.

If a community member engages in unacceptable behavior, the community organizers may take any action they deem appropriate, up to and including a temporary ban or permanent expulsion from the community without warning (and without refund).

If You Witness or Are Subject to Unacceptable Behavior

If you are subject to or witness unacceptable behavior, or have any other concerns, please notify an organizer as soon as possible. Organizers are wearing meet.js Summit 2019 t-shirt. You can also contact the organizers via Twitter @meetjs or email

Organizers are available to help community members engage with local law enforcement or to otherwise help those experiencing unacceptable behavior feel safe. Organizers will also provide escorts as desired by the person experiencing distress.

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meet.js is a series of events, meetups, and workshops regularly organized in more than eleven cities in Poland. meet.js is one of the largest thriving JavaScript communities in the country, it has gathered over 30000 professionals combined.

The culmination of these events is a yearly conference called meet.js Summit. This year it will happen on the 30th of September in the International Congress Centre in Katowice. The conference is filled with an array of web development professionals and it is a great opportunity to share experience with one another, network and keep up to date with the newest trends in web development.

Have any questions? You can contact us at