The Age of the Dopamine Deluge - Looking Back on 2025

Introduction 🙋‍♀️

Just like last year, I attended the retrospective gathering held within Geul-tto this year as well. I took a quick look back at 2025, and I realized it was a year packed with so many events.

It’s clear that I’m even more of a dopamine-seeking person than I thought, and whenever I found a particular activity fun, it often served as a catalyst for trying something else. This tendency of mine was woven throughout my entire life this year. I tried various things at work, and in my daily life, I think I truly did my best to enjoy life to the fullest. While I considered it a happy year, it was also a year in which countless branches of thought spread out in every direction.

**A Dopamine-Driven Year—I’d like to take some time to reflect on the experiences I had and the major insights I gained over the past year.

2025 Briefing 📜

Summarizing major events by category

📌 Company

• First half of the year: Focused on adding new features to the main project and resolving technical debt
• August–October: AI agent PoC project
• September–November: Participated as a Tech for Impact mentor
• September: Operated a booth at the if Kakao demonstration
• November: End of a 5-year journey; resigned

📌 Activities

👥 Community

• January–March: Participated in the 10th cohort of Geul-tto
• April–June: Served on the Data Ya Nolja organizing committee

📖 Study Groups

• April–July: ISLP study group
• July–October: Study group to read “Practical Guide to NLP and LLM” from cover to cover
• November–December: Study group to read “AI Engineering” from cover to cover
• November–: LeetCode Algorithms Study Group

📌 Travel

• April: Group trip to the Goseong Mangrove Forest
• May: Trip to Eulwang-ri (while attending the Hans Zimmer concert)
• September: “Geul-tto” admin team retreat in Gangneung
• November: Day trip to Daejeon
• December: Solo trip to Daejeon (while attending the Tech for Impact成果発表会)
• December: Solo trip to Goseong Mangroves

📌 Conferences

• May: Attended the AWS Conference
• June: Attended Data Ya Nolja (as a member of the organizing committee)

📌 Cultural Activities

• January: Went to the Geul-tto sledding hill
• January: Went to the Geul-tto Sledding Park
• March: Watched the movie Brutalist
• April: Walked around Suwon Hwaseong Fortress
• April: Attended a Coldplay concert
• May: Attended Hans Zimmer’s concert in Korea
• June: Attended the Alex Kito & Jonathan Bertin Photography Exhibition
• July: Attended Joe Hisaishi’s concert in Korea
• July: Watched the Coupang Play vs. Newcastle soccer match
• October: Visited the Pikmin pop-up store @Yeoju Premium Outlet
• October: Participated in the Disney Run
• November: Attended a wall tattoo studio gathering
• November: Attended a Samsung Philharmonic Orchestra concert
• December: Visited an exhibition at the Lee Ungno Museum of Art
• December: Watched the movie Zootopia 2
• December: Attended Lim Dong-hyuk’s “Christmas Music Gift” (Chopin Recital) @ Namyang Shrine of Our Lady

📌 Other

• February: Tried a strengths assessment after being introduced to it (my top strength is “Action”)
• May: Reunited with my uncle and aunt from the U.S. for the first time in 20 years (I have such fond memories of them, so I was thrilled to see them)
• September–December: “100 Days to Go” Challenge (The Miracle of 100 Days!)
• December: Made a comeback with a pixie cut (I feel like I’m sick because I can’t grow my hair out)
• December: Once again… started studying English!
• So many coffee chats… both at work and through extracurricular activities… a whole lot…

2025 Event Log ✨

☑️ Geul-Tto, Geul-Tto, and More Geul-Tto

• Geul-Tto is a must in 2025 as well. Although the official activities for the 10th Geul-Tto cohort have ended, as of December 2025, we’re still quietly keeping in touch and meeting up separately.
• The biggest reason I continue participating in Geul-tto is, without a doubt, the “warmth.” There are so many people who are like the coal ash described in Ahn Do-hyun’s poem “I Ask You.”

A Few Memorable Stories from After Official Activities

For stories up through March, please see the [Geul-tto 10th Cohort Review][[[14]])!

• I received a fan letter (?)

  • Around early April, someone who wanted to get to know me wrote me a letter, and I remember being so grateful.

    • While there are so many people who care about me, the reason this story stood out in my memory was because they sent me a genuine “handwritten letter”… It’s been so long since I’ve received a handwritten letter

  • I was a little obsessed with my Geul-tto activities (p), and even though I was just talking about myself, hearing that it gave someone strength and courage makes me realize just how wonderful that is.

  • Not long ago, an influencer wrote a post reflecting on a large-scale event they’d hosted, mentioning that lately they’ve been thinking about “the feeling of liking and cheering on others.”

    • I think people who have “feelings of liking and cheering on others” are those who trust the person they like and have the courage to tentatively open up their hearts—which is why the courage of the person who wrote me that letter stuck with me even more.
    • When was the last time I actively offered that kind of encouragement to someone?

    

• I went to Goseong Mangrove, a famous workation spot, with like-minded people.

  • Even though things didn’t go quite as planned, it was a wonderful trip. Here’s the travel review I wrote after returning.
  • The fact that conversations with like-minded people can easily take up 30 hours during a two-day, one-night trip... I think that’s the reason why I need to surround myself with good people, and why I, too, must be a good person to them.

• I went on a team-building retreat with the Geul-Tto staff to Gangneung.

  • This was a time when my work stress was at its peak, and I even considered canceling the trip, but I just closed my eyes and went anyway.

  • Sure enough, thanks to everyone’s thoughtfulness, I came back feeling truly rejuvenated. When things get tough, take a step back and rest. I think that’s really important.

    

A lot of people joined the trip—some I see often but am still happy to see,
others I hadn’t seen in a while and was glad to catch up with,
and some I hadn’t had a chance to talk to much before, so I took this opportunity to strike up a conversation.
The more we talked, the more I realized they’re all such wonderful people.
>
No matter what situation I’m in, they see the best in me and sincerely cheer me on for my future. I’m just so grateful 🙏
> (Excerpt)
> As always, when you’re debating whether to go on a trip or not, you should just go lol. I think of it as a lovely gift for my future self 🎁
>
> - From a post by the Geul-tto admin team about their retreat

• I’m participating in “100 Days Left” with the goal of “consistency.”
  • My 100-day missions were “read the news every day,” “take a photo of the sky,” and “(starting on Day 51) arrive at work at 8 a.m. with minced garlic.”
  • Out of the 100 days, I completed all my missions on 85 days.
• I did at least one mission on 13 days, and there were 2 days when I didn’t complete any of them.
  • An 85% success rate seems like a decent effort, and I hope this consistency continues...!

☑️ Data Yanolja and ISLP Study Group

• The reason I’ve combined the Data Yanolja and ISLP study groups is that these were activities I found more challenging than expected

• I applied for 데이터야놀자 준비위원회 based on the idea of “how can I make better use of my experience as a Geul-tto staff member?”

  • However, I joined thinking it would be more like a “neighborhood meeting planning committee” rather than the “Geul-tto” crew activities
  • Once I actually joined, I found that meetings were conducted more systematically than I expected, and activities were organized by specific teams.
    • In the Content Team I joined, we handled everything from A to Z related to the presentation content
      • From selecting presenters to supporting them, filming presentations, and editing videos—I never thought I’d be editing videos again
  • Still, it was enjoyable to contribute to the conference preparations by leveraging my experience. (This is my dopamine...)

    

• ISLP 스터디 is a statistics study group, so I didn’t really have to join, but I participated because I really wanted to understand our company’s products

  • Since our company’s products are ultimately research-related, statistics play a major role, and the company’s statisticians do explain a lot of it.
    • However, since I didn’t understand the underlying mechanisms, I guess you could say I was left feeling a bit unsatisfied.
    • When I looked at the table of contents and thought, “Oh, I need to study this,” I dove right in, but each session turned out to be one challenge after another...

• There’s still so much I don’t fully understand... but I was able to grasp the context of the statistics!

• It’s become much easier for me to understand how our company’s products actually work, why those statistics are necessary, and which parameters to use.

• At the end of the study group, some members picked my presentation as the “most memorable one,” which made me think, “I guess I really did work hard after all.” (And they were even DA and DS team members—didn’t they give me some recognition? Lucky me!)

• The activities were much more in-depth than I’d expected, so while it’s true I put in a tremendous amount of personal effort, I ultimately learned a lot from the people I worked with.

• When tackling activities that proved more challenging than expected,

  • I reaffirmed that it’s important to continuously observe the actions of others who are more skilled than me and keep experimenting with how to apply my own “meta” insights in those situations.
  • That’s how my meta-perspective builds up and my world expands.

☑️ Trying things I hadn’t done at work

• While it goes without saying that performing my assigned duties should be the top priority, I’ve always thought that, as a member of society, it would be good to try out many other activities as well.

  • The easiest approach was to find and do things “within the company.” Even though they’re done within the company, I tried things that felt outside the scope of my regular work.

• Experience running the “if kakao” demonstration booth

  • At this year’s if Kakao, in addition to the presentation sessions, there was a day called “Demostation” aimed at fostering technological exchange among affiliate companies.
    • I had been wondering how the company could utilize my experience as a member of the Geul-tto Meetup crew and as part of the Data Play preparation committee, and I thought this would be a good opportunity to apply that knowledge, so I applied.
    • I brainstormed ideas and developed scenarios with my team members on how to explain our AI-powered work automation to others
  • What I realized then was that explaining my knowledge to others verbally is now a little less daunting
    • Unlike during work or meetings, I was particularly afraid of giving presentations.
    • I used to have such severe presentation anxiety, but I might have overcome it a little.
    • And I’ve also noticed that the more I explain things, the better I get at it, haha.

    

- Participated in Tech for Impact’s college student mentoring program - This program, run by the Kakao Impact Foundation, involved mentoring college students on their semester-long projects. - I continuously followed up on the projects’ progress and occasionally provided guidelines for solving problems. - **It’s important to provide direction rather than just giving the right answer**. As the Talmud says, you shouldn’t give someone a fish; you should teach them how to fish. This activity served as a good reminder of that point. - And one thing was certain: when it came to the development process, there was so much more I could share with the students.

• It was interesting attending the final presentation.
• Overall, they incorporated a lot of AI, so the quality of the ideas was very high. (The future of our country is bright, so bright.)
  • Thoughts that came to mind while listening to the presentation by the team using Raspberry Pi
• Come to think of it, my journey into development began with IoT education, so I wondered if I hadn’t been focusing too much on web development for a while.
  - Looking back, when the term “Fourth Industrial Revolution” first emerged, AI was simply the first to create a boom among the technologies that garnered attention, but haven’t IoT and blockchain also been steadily advancing?

  

☑️ The End of a 5-Year Journey: Resigning

• I did my best at the company and performed well in my own way, but I’ve decided to resign.

• There isn’t just one single reason. It was a decision based on a combination of many factors.

  • The biggest reason was the realization that my current company could no longer satisfy my need for “direction in my life” or “reflection on my career.”
    • It seems difficult to align my direction in many ways
  • The reason I decided to resign rather than switch jobs is that
    • I needed to take a step back and assess my current situation.

• Just as a computer starts to lag when CPU usage is too high, I felt I was in that kind of situation.

  • It’s really hard to prepare for a new job while still working at your current one.

• Since I used the energy I would have spent preparing for a new job to focus more on my current work or engage in other activities, I just couldn’t do it…

• I really admire people who manage to do both well.

• I had a ton of coffee chats before leaving. Especially during the last two weeks or so...?

  • I had many conversations not only with developers, DEs, DSs, planners, designers, ML engineers, and researchers within my own business unit, but also with people from other business units.
  • Among the things I heard during those coffee chats, the ones that come to mind are “나가서도 뭐라도 잘할 사람이다”, “사는 게 걱정 안되는 사람이다”
    • While walking with a teammate across the “Bridge of Career Changes,” some mothers visiting Pangyo asked us to take their picture, so I channeled my inner photographer(?) and did my best to take the shot for them
      • Seeing this, a team member who was watching from the side smiled and told me, “Anyway, I’m not worried about you.”
    • I tend to have a bit of unfounded confidence myself, but I thought I could go through life with a little more well-founded confidence!

☑️ 10km Marathon at the Disney Run

• As I started running a little here and there in 2024, I decided to make 2025 “the year of running.”

  • But when the year actually rolled around, I didn’t run much until February.
  • So, my new goal was to absolutely run a 10km marathon at least once.

• I signed up for the Disney Run and, luckily, got selected.

  • From the day I found out I was selected, I went for a run around my neighborhood almost every 2–3 days.
    • In the end, if you create the right motivation, you’ll get things done. That motivation is a goal you really want to achieve!
  • And I finally finished the 10km race! I didn’t think I could do it, but I did it

• I still haven’t been able to slow my pace, but I don’t really care. I used to struggle just to run 10 meters, but now I’m running 10 km

☑️ Visiting Daejeon and Goseong: Deliberately Seeking Out Places Full of Memories

• Right after quitting my job, I visited Daejeon and Goseong. I made a point of visiting places filled with childhood memories.

• When I went to Daejeon, I visited my high school.

  • I’d also visited my middle school a few years ago, and I remember thinking a lot about “my younger self” when I went there.

  What was 14-year-old Zhengniu thinking back then?
  34-year-old Zhengniu asked.
  How much does the adult self I dreamed of back then
  resemble who I am now?

  • Thoughts I jotted down after visiting my middle school
  • I had similar feelings after visiting my high school

  • It had been far too long since I’d been back to my high school. Luckily, it was open to the public, so I explored the first floor and ran 10 laps around the track
    • As I recalled what happened on the playground and the experiences I had throughout my three years of high school, the things I loved and the things I was good at came flooding back one after another

- When I went to Goseong, I visited Sampo Beach. - Sampo Beach was a vacation spot I used to visit every year with my family when I was a kid. - Since I always went in the summer, I hadn’t realized it before, but Sampo in the winter was incredibly quiet. It wasn’t just quiet—it was eerily silent. - But it was actually kind of fun being the only person on that vast beach, haha. It was a bit of a thrilling experience. - The reason I went out of my way to visit this place from my past was that - Sometimes I want to bridge the gap between who I was as a teenager—or who I dreamed of becoming back then—and who I am now. - When I visit places like this, stories from the past suddenly come to mind. - I wonder if those might serve as hints for how I should live my life going forward? - Of course, I’ve changed a lot from who I was in my teens and twenties, but since my “true nature” doesn’t really change, I sometimes find courage by thinking about who I was back then.

Thoughts for 2025 💡

💭 To my past self who quit my job: Well done, anyway!

• Whether it was the best decision or the worst, it’s okay—I’m going to live a good life anyway!

  • I’m the type who keeps encouraging myself with a bit of self-confidence; jokingly, I tend to engage in “positive self-gaslighting” (?) haha

  • Of course, the word “anyway” is too vague. Don’t forget that it should encompass the countless actions, thoughts, and reasons that determine the direction and quality of my life

    • This is to remind myself not to fall into the arrogance of thinking things will just work out on their own as time goes by..!

  • Let’s tackle things one by one—come on!

💭 The reasons behind my “actions” seem to be stuck in the “past.”

• This year, too, I found myself wondering, “Why was I chasing dopamine so relentlessly?”

  • But it seemed a bit different from the reasons I’d had in the past

• Perhaps I spent a lot of time reflecting on the past—thinking things like “I used to think this way,” “I used to be good at this,” “I used to want this!”—and to some extent, this became a driving force behind my actions...

  • In 2024, I said “I’ve regained my lost identity,” and that sentiment seems to have carried over to the present.
  • So I think I felt a greater sense of accomplishment when I tackled, one by one, the things my past self had wanted.
  • It wasn’t like that every time, but it happened quite often.

• Reflecting on the past isn’t a bad thing in itself! However, because I was simply acting based on “what,” it felt like I wasn’t really gaining much from it.

  • So I felt I needed time to sort out thoughts like: Why did I think that way back then? What did I want to do? How is it related to my present situation? Should I continue with this in the future, or not? Why would I continue? If I do, what exactly will I do?

  • Recently, when I visited nostalgic places in Daejeon and Goseong, I decided to reflect on my childhood memories and consider whether they’ll be helpful going forward.

💭 I want to cultivate a calm inner self. I want to simplify my life.

• This is an extension of the thoughts I mentioned above.

• After going all out on dopamine-fueled activities, I realized that while it was great to have had such diverse experiences this year, I’ve now reached a point where it’s starting to feel a bit overwhelming (my introversion—which nobody knows about… I’m telling you, it’s real…;)

  • Seeing how I’d been impulsively making plans all year, I even scheduled a “no plans” day. Since the second half of the year, my commitments have naturally decreased, so I haven’t had to go that far anymore, but

• So I found myself wanting things to be calmer and simpler.
  • But then again, I feel like I’ve been thinking this way for several years now.
  • It’s more like a form of spiritual cultivation, so it’s not something that ends in just one year.
    • Come to think of it, things are actually calmer and simpler now than they used to be... haha;;

💭 I want to become a consistent person.

• I used to think of myself as someone who was comfortable with change and variety, but do I really need to go out of my way to make so many changes anymore?

  • I have (to exaggerate a bit) 100 hobbies, and I used to enjoy them by rotating through them.
  • It’s true that doing so many different activities in such a short time has become a bit overwhelming, and I definitely poured a lot of energy into it.
    • What I overlooked was that my past self and my present self are different—yet I assumed I could still do things the way I did back then. Perhaps I failed to realize that while I used to have the stamina and time to tackle new challenges almost every day, that might not be the case now. After all, I’ve changed too.

• So rather than dabbling in various things for short bursts, I’ve come to want to stick with even just one thing consistently.

• I’m a natural energy-emitter, but if I practice “convergence” as a form of self-cultivation, won’t I eventually reach a balance between emission and convergence? I feel like I’m on my way to finding that sweet spot where my mind feels at ease.

💭 What will the next chapter be?

• I’ve been thinking about this constantly since the beginning of the year, right up until I quit my job.

• Up until around February, thoughts like “I don’t know how to shape my next chapter” and “Wouldn’t it be okay to just keep living like this?” kept popping into my head.

  • It’s true that I was settling for the status quo, but in a way, wasn’t that a time when I felt emotionally stable at work?
  • I also thought staying put was the right choice because the vision for my next chapter was practically nonexistent.

• Then, as the second half of the year began, I started wondering, “Is this really how I should be living?”

  • Seeing the people I looked up to at the company gradually move on to other places served as a catalyst.
  • Another reason was realizing, through conversations with others, that this wasn’t the life I truly wanted.
  • That ignited my thoughts about the “next chapter,” and while the details weren’t clear yet, thinking about the big picture gave me the confidence to decide to quit.

• Once I left, the various elements that would shape my next chapter began to emerge little by little

  • So, first of all, I started studying English again
    • Back when I took a leave of absence from college, whenever I didn’t know what to do, I’d just study English—and it had a huge impact on my life
    • Around that time, I came to believe that learning a language expands my worldview, and studying six languages even became one of my life goals though I’m not doing it right now
    • Although, as time went on, I’d forgotten about that as I focused on my main job...! Thinking about the future, I realize that studying languages can only benefit me!
  • Ideally, it would be something related to development, but even if it’s not directly related, I’ve been telling myself lately that if it’s something with enough value to help shape my next chapter, I should give it a try.

💭 All in all, 2025 was an incredibly enjoyable year!

• Whatever the reason, I did a lot of the things I wanted to try, so honestly, it was a year without regrets.
• Since I was so active, I’m sure that opened up countless new options… Anyway, isn’t this just part of living a colorful life?
• As this year came to a close, I discovered the “version of myself I want to embrace,” but since life is a long journey, I might want to branch out again someday.
  • Well, I’ll just have to enjoy it as it comes~ I want to live life to the fullest~

💭 (Bonus) Thoughts While Reflecting on My TODO List

When I wrote my 2024 retrospective, I also made a to-do list for this year, and I wanted to check “how well I stuck to it.”
However, since that seems a bit off-topic for this post, I’ve written it up separately and concisely on a Notion page.

In Closing 🤗

At the end of 2024, I said, “I hope 2025 will be a year I can look back on with satisfaction.” It actually turned out that way, and I think I was truly happy.

It was a year where I often acted simply driven by dopamine, but looking back, not a single thing turned out to be toxic to me, so I think 2025 will be an even more memorable year. I believe that when my actions blend with the flow of time, life tends to move upward, so I think this year was a step forward than 2024.

And since I’m someone who started my career with my fair share of (?) difficulties, the decision to quit my job took quite a bit of courage—but I’ve already taken the plunge, so what can I do? I need to live with my eyes on the future! I’ve drawn a lot of inspiration from my past self, so I hope that in 2026, I’ll find my next step and that by the end of the year, I’ll be able to say, “This chapter of my life is OO.”