Mercari's First Large-Scale Global Hackathon, Mercari Euro Hack 2018 in Poland


Japanese Ver.

Hi! This is Madoka from the Onboarding Team.

On October 20-21, Mercari went to Poland to hold Mercari Euro Hack 2018: Implementing Sharing Economy Solutions, a hackathon for product managers, engineers, designers, and other IT talent from all over the world. Today I’d like to show everyone some highlights from the event!

Check out the video below for some clips!

Why hold a hackathon in Poland, where Mercari is virtually unknown?

Eastern Europe is full of technology and people talented enough to win numerous hackathons on the international level, and as a result, many global tech companies are turning their attention toward the region. As an aspiring global tech company ourselves, it’s an extremely appealing area to break into. We wanted to show the skilled engineers of Eastern Europe what kind of technology Mercari is working on, and so we decided to hold Mercari Euro Hack 2018 right in the heart of Europe—specifically, Warsaw.


But virtually no one in Poland knows about the Mercari app. On top of that, very few Japanese companies recruit in Eastern Europe, so the idea of working in Japan is rather uncommon. We held a hackathon in a country where Mercari had zero name recognition once before, but this was an even greater challenge none of us had dealt with before.

So where did we start? For this hackathon to succeed, we needed to not only make a name for Mercari, but also promote the idea of working and living in Japan, and we needed to do both of those from the very start. We held online seminars for European audiences, worked with engineering tech communities to get the word out, and did a lot of marketing. Through all of these, we encouraged those we met to join our hackathon.

And in the end...?

We had over 560 people apply to our advance screening round! We had applicants from not only Poland, Hungary, Ukraine, and other European countries, but even Egypt and Brazil.

The day we were all waiting for: Mercari Euro Hack 2018!

After the advance screening round, 91 people in 30 teams moved on to the event itself: Mercari Euro Hack 2018. Participants were given a challenge: “In the next 24 hours, plan and create a prototype of a technical solution to the issues faced by a sharing economy today.” At the end, the teams would present their prototype in front of the judges.

Participants focused on creating their prototype

To help the participants produce their best work, we provided specific times and areas where they could immerse themselves in their work. We also offered mentorship sessions with Mercari engineers to give advice and hints. Even Mok, the CTO of Mercari US and one of the judges, answered questions from the participants. On top of that, we set aside time for other Mercari members to speak about the company culture and technical challenges Mercari faces.

Mok Oh, CTO of Mercari US, giving advice

And of course, you can’t have an overnight hackathon without relaxation spots! We set up activities like foosball and darts, plus massage chairs to help participants get some rest on their breaks. It was pretty common to see participants and Mercari members eating together in the food area; the overall atmosphere of the event was very casual and fun.

Participants taking a break to relax

Finally, each team gave a presentation in front of the judges! The teams presented really cool technical solutions using technology like machine learning and AI. All of the presentations were so good that the judges had a really tough time narrowing it down to the top three... The heated discussion went on until the very last second before the announcement of the winners.

Which of the 30 teams from all over the world came out on top?

The first prize went to (drumroll please)...Giant Leap Lab, who presented their idea to use image recognition technology to improve the selling experience on C2C apps! Congratulations! The judges were particularly impressed that despite having only 24 hours, they managed to create a working prototype using extremely difficult technology.

In this hackathon, we wanted to see just how advanced the participants’ technical skills were, and so in the evaluation, the judges paid particular attention to how high-level the solutions were, rather than the originality of the idea or the presentation skills. Giant Leap Lab’s presentation was a perfect display of their high-level technical skills.


Mercari Euro Hack 2018 was born from the idea that we wanted to show the skilled engineers of Eastern Europe what kind of technology Mercari is working on. In a country where no one knows Mercari or considers working in Japan, we weren’t sure how holding an event like this would go, but we were joined by participants who were extremely skilled and passionate, and in the end it was a great success. When we asked the participants about their experiences, they had great things to say:

Yosyp, a member of the Hack team: This hackathon was organized and run really well. Mercari created an environment where we could work efficiently, so we were able to concentrate on proposing solutions and making our presentations. Through this hackathon, I realized that there are still a lot of opportunities for self-improvement and development. Also, I was really excited to meet people from all over the world. It was a very different experience than anything I’ve done before.

As I wrote in the introduction, Poland and the rest of Eastern Europe is full of high-level IT talent. Poland’s government places a strong focus on startups, and a number of the teams participating in the hackathon are actually running startups themselves. In addition to seeing firsthand how passionate these ambitious participants are about technical challenges, we were also able to feel the great potential of startups through this event.

Related job postings

mercari - Jobs