I originally tended to leave event reviews briefly and dryly in passing, but recently many people who have become Twitter friends, as well as others who participated in PyCon JP, have been writing posts. I wanted to leave a trace of a Korean attendee's experience and create an archive that might be useful to someone as a reference.

Deciding to Attend

I've been participating in PyCon KR since around 2016, making this my 10th year, so I've developed quite an attachment to the Korean Python community. I've participated as an individual sponsor and operated booths as a community sponsor (vim.kr, fedidev.kr, etc.). Despite my attachment to the Python community in various capacities, I had never participated in a foreign conference. Having earned my living with Ruby for more than half of my career, I did attend RubyKaigi 2023 around 2023.

Anyway, although I had been thinking about consistently participating in overseas conferences, particularly in Japan, I kept postponing it due to personal matters. Recently, after quitting my job and becoming free, I happened to be able to attend PyCon JP and took the plunge. In terms of Japanese language proficiency, I had cleared all stages in Duolingo, but that's quite different from being able to converse freely. Still... I focused on the significance of participating. (In truth, the temptation from Twitter acquaintances, including Kwonhan, who suggested going to PyCon JP together was too strong)

So, on August 18th, I boldly purchased a PyCon JP ticket along with a flight ticket to Japan.

Before the Event (09/24) ~ PyCon JP Day 0 (09/25)

09/24 3 PM, arrived in Hiroshima with Kwonhan Bae (darjeelingt) from Cheongju Airport. 09/24 6 PM, ate okonomiyaki at a place called Kanransha near our accommodation. 09/25 1 PM, spent time with people from Korea including Doyun Kim, Youngeun Lee, and Namsu Hong, eating conger eel rice bowl and visiting the Hiroshima Atomic Bomb Dome.

Then, 09/25 6:30 PM. I participated in the DrinkUp party hosted by Findy. Since I wasn't fluent enough in Japanese for free conversation, I awkwardly communicated in English. The person right in front of me was a data engineer working at Findy. I had written "Vim" in my introduction, so we shared an inner connection that transcended language.

"Oh, Do you use Neovim?" / "YEAH!!!" / "You also use Wezterm?" / "YEAH!!!" - Findy data engineer's PyCon JP review

tiangolo, the developer of FastAPI, was also there, and we took a photo together.

For the second after-party, I went to the Drink Up party hosted by the Python Asia Organization. I happened to see tiangolo again and remember talking a lot about Korea.

I also went to a third after-party. I think I was quite drunk by then, but my clearest memory is feeling threatened because the person right next to me was an Emacs user. I recall that Takanori, who bought me beer at that time, was also an Emacs user.

PyCon JP Day 1 (09/26)

It was the first day of PyCon JP. Perhaps due to drinking too much the night before, I woke up late and rushed to the venue, determined not to miss the first session.

"Dress Code: How Python Writes the Future of Fashion": This was the first session of the event day. I didn't know what it would be about and just attended with the mindset of "let's listen to any session in English." For such a random choice, the content was quite satisfying. It introduced how Python can be usefully applied in the fashion industry. The presentation covered how to create products using noise generation functions based on sin functions, generative AI, embroidery pattern generation DSL, and more.

"マイエディタのすすめ" (Recommending My Editor): As a Neovim enthusiast, I was drawn to the keyword "エディタ" (editor) and went to listen. The presenter had developed "an editor that works cross-runtime and outputs markdown format writing as docx files." "Editor development itself" was already an interesting topic, but what made it more fascinating was that the presenter wasn't a professional developer but a lawyer working in Hiroshima. He shared anecdotes about creating his own tools while working as a lawyer. I missed some parts but enjoyed the presentation. (Editor introduction page)

After this, there didn't seem to be any more sessions I wanted to attend, so I mostly wandered around the sponsor booths, but my battery died so I don't have any photos. Unfortunate.

The event concluded with a keynote session by tiangolo, the creator of FastAPI. I gained insight into tiangolo's development philosophy, which had many aspects worth emulating. A memorable quote was, "Innovation is a side effect of solving problems."

I also found it unique that the keynote session was placed at the end of the event. (Note: At PyCon KR, keynote sessions are at the beginning of the event, so you have to wake up early and rush to attend them.)

In the evening, I attended the Official Party, and since I hadn't eaten much at the DrinkUp party the night before, I focused intensely on the buffet food. As for networking... I didn't have much energy that day, so I mostly just listened.

PyCon JP Day 2 (09/27)

It was the second day of PyCon JP. Although I hadn't drunk excessively, I still had a hangover. I ended up being late.

"How I Built a CPU for Fun (and Didn't Learn Verilog)": This session presented the experience of developing a CPU using a Python-based DSL library (Amaranth) instead of HDLs like Verilog. During my undergraduate studies, I only learned the theory in logic circuit/computer architecture classes and didn't get to practice with HDLs like Verilog as friends at other universities did. Perhaps because of this, the session felt like a completely different world and was fascinating to me.

"Webアプリケーションにおけるパスルーティングアルゴリズムの解剖" (Web Application Path Routing Algorithm Anatomy): I attended this because I enjoy sessions that examine the internal implementation principles of libraries/frameworks. The session explained how routing algorithms work when processing the path field in request headers to provide responses, and the pros and cons of VM-based and Trie-based approaches. Since it was in Japanese, I couldn't understand everything completely, but I attended to get ideas on how to approach and prepare for presentations. I'll probably watch it again when it's available on YouTube.

"Python製RDBMSで理解する、データベースのピース 〜コードのステップ実行とヘックスビューアーで内部動作を追ってみよう〜" (Understanding Database Pieces with Python-made RDBMS - Tracing Internal Operations with Code Step Execution and Hex Viewer): This could be considered personal research. Literally, a web developer implemented a DBMS from scratch in Python as a 'side project' and explained step by step with code how it was implemented. The session introduced what components (Lexer, Parser, Planner, Buffer Manager, ...) make up a DBMS and how they were implemented. Seeing someone create something like this as a side project out of a desire to understand from the ground up made me reflect on myself. I had only been looking for good textbooks...

The Day 2 keynote speaker was Ami Otsuka, author of the book "100-Day Challenge". Overall, much of the content was familiar to me, covering the story from the book's publication to what happened afterward. (In fact, I missed many parts because I couldn't understand some of it.) What had changed was that she had started a one-person company around December last year and had been doing many interviews. As a young professional who hadn't graduated from university that long ago, her presentation really conveyed the traces of her hard work. Before the keynote, she did a "100-day challenge," released an app on the App Store, and even demonstrated it live during the keynote. I couldn't try it since I'm not an iPhone user. I had many thoughts while reading the "100-Day Challenge" book, and I definitely felt that "people who consistently take action are different somehow." For a review of the "100-Day Challenge" book, you can refer to this thread.

In the evening, I went to the DrinkUp party hosted by PKSHA Technology. I had more energy than the previous day, but my Japanese still wasn't flowing smoothly. Fortunately, there was an engineer who frequently travels to Korea, so I thought "I should at least show my status as a Seoul restaurant expert" and marked a few recommended restaurants on Google Maps for them.

As the DrinkUp party was ending, they were looking for people to join a second after-party at a karaoke place, so I experienced karaoke too. I showed them "how Koreans enjoy noraebang (karaoke)," and the response seemed positive. I played until around 1 AM before heading back.

Afterward (09/28)

The day after PyCon JP ended, a Sprint event was scheduled. Since Sprints are an essential part of PyCon, I had signed up for it. However, because I had so much fun at the Day 2 after-party, I arrived late at the Sprint venue around 11:30 AM. I didn't actively participate in the Sprint but observed how other tables were conducting their Sprints. In Korean terms, it's similar to "Mogakko" (Moyeo Gakja Koding - "gathering to code individually"), but not much different. There were tables teaching how to contribute to open source, tables handling administrative tasks related to the event, and tables where people were just doing whatever they wanted. I sat at a table where everyone was doing their own thing, observed the situation for a while, and then left with Kwonhan (darjeelingt) to tour Hiroshima.

In the evening, there was another after-party where I enjoyed some free beer. (Thank you very much, Takanori)

Overall Review

This was my first developer conference abroad since RubyKaigi 2023. While I enjoyed RubyKaigi too, this time I had a more meaningful experience by attending second and third after-parties and networking with other foreign developers.

There were several impressive points during my participation:

There was a lot of content available for foreigners. From the perspective of a foreigner who isn't very fluent in Japanese, the available option at a developer conference is to attend sessions in English. Locals can attend sessions in their native language, but foreigners often face language barriers. I knew that Japan has an excellent domestic environment where information is readily available in their native language, but PyCon JP had a significant number of sessions in English. There were even quite a few foreign speakers and organizers. In many ways, consideration for foreigners was evident throughout.

There were sessions on relatively diverse topics. Like RubyKaigi, there were sessions where contributors directly explained library/core implementations, as well as sessions by a lawyer who developed his own editor, a medical physicist who built a community of 1,000 people, and someone who implemented an RDBMS in Python. While I've enjoyed PyCon KR in its own way, there was definitely a different variety of content.

There were many networking opportunities. Excluding arrival and departure days in Hiroshima, I think I networked almost every day. On Day 0, there was the Findy DrinkUp Party, on Day 1, the Official Party, on Day 2, the PKSHA DrinkUp Party, and there was even a networking party the next day. Since I wanted to meet more people while in Japan and was considering job opportunities there, these were great opportunities. Thanks to these networking events, I was able to take a photo with tiangolo and even received a casual interview offer from a company. (Which one is a secret) + The second and third after-parties were also great.

If I participate again... (which I definitely plan to do no matter what)

• I need to bring a power bank.
• I need to bring a coin purse.
• I need to practice Japanese properly. (Duolingo had its limitations)
  • But I wonder if there's a Discord server or similar where I can casually interact with Japanese developers? It would be nice if there were more Python developers.
• I also need to practice English to the level where I can converse fluently.
• I should definitely apply as a speaker. (If I find a job using Python...)

On the other hand, I also think "It would be nice if PyCon KR had more content that foreigners could enjoy." Even if we can't prepare event content, I think it would be fun to prepare places where foreigners can mingle.

I'm open to contact.

My experience at this PyCon JP was excellent, and I want to continue participating regularly. If I participate next time, I plan to go fully prepared. This time, six of us from Korea went as a group chat, but next time, I'm thinking of gathering about 15 people to go together. And I'd like to get to know more Japanese acquaintances.

• Email: jaeyeol.lee@hey.com
• X(Twitter): @kodingwarrior
• Fediverse: @kodingwarriorJaeyeol Lee, @kodingwarriorJaeyeol Lee (a.k.a. kodingwarrior)
• Instagram: @kokoko_kojima_
• Github: malkoG

Ah, I want to go to PyCon JP again.