Taeho Kim
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Notes

Short notes and observations that have not turned into essays yet.

Startup · AIJul 16, 2026

What Solo AI Founders Need Beyond AI

AI can make solo entrepreneurship extraordinarily powerful, but experience, judgment, discipline, and resilience determine whether a founder can direct that power well.

LinkedIn3 min
AIJul 15, 2026

Send Me the Mental Model, Not the AI Email

When AI writes the message, the sender's underlying mental model matters more than polished output. Share the intent that should become the prompt, system, and result.

LinkedIn1 min
HealthJul 10, 2026

What Comes After the End of Drinking Culture?

Ideas I have shared over the past three years about changing attitudes toward alcohol, health, and longevity were featured in JoongAng Ilbo. The article traces the path from wearables and wellness software to personal digital twins and AI-assisted decision-making.

LinkedIn4 min
AIJul 9, 2026

Real-Time Interpretation for Everyone

AI is making real-time interpretation available to everyone, but the deeper value of studying languages was never just linguistic skill. Curiosity, courage, and openness to difference remain powerful lenses for navigating an AI-shaped world.

LinkedIn2 min
Engineering LeadershipJul 6, 2026

Why Understanding Doesn't Always Change People

A Q&A about why self-knowledge does not automatically lead to behavior change. The answer frames change as a game people choose for themselves, not something a manager can force.

LinkedIn4 min
Startup · AIJul 2, 2026

When Startup Capital Becomes AI Tokens

AI is shifting a startup's biggest expense from developer salaries to tokens, changing both the case for fundraising and the value of enduring uncertainty with the right investors.

LinkedIn2 min
Engineering LeadershipJul 2, 2026

Productivity Without Purpose Is Waste

A short note on why the question 'productivity for what?' feels refreshing in the AI era. Without purpose and philosophy, productivity gains can become wasted tokens or wasted people.

LinkedIn1 min
AI · Data & Decision-MakingJun 23, 2026

Decision Fatigue and AI Delegation

A note on sharing decision-making with AI so leaders can reserve their energy for a few high-quality choices.

LinkedIn2 min
HealthJun 22, 2026

Put Health First, Then Use AI

A note arguing that sleep, exercise, and nutrition should come before work, and that AI can help make that win-win possible.

LinkedIn3 min
Startup · AIJun 21, 2026

Running a Company With AI Agents

An interview-style note on why a startup can maximize AI agents, what humans still do, and how organizations must clarify outcomes.

LinkedIn6 min
HealthJun 19, 2026

HRV Works for Apple Watch

A short LinkedIn note introducing HRV Works as an Apple Watch app for tracking biological age and aging pace.

LinkedIn1 min
HealthJun 17, 2026

How Much Chairmen Value Exercise

A dialogue-style note on why top executives treat exercise as a strategic asset rather than a hobby.

LinkedIn2 min
Startup · HealthJun 9, 2026

Why Taeho Kim Was Meant to Build Tab0

A reflection on Taeho Kim's long-standing focus on longevity, his impact as a Kakao Ventures EIR, and why he is uniquely positioned to build personal decision intelligence.

LinkedIn3 min
StartupJun 3, 2026

The Founder Must Use the Product

A blunt note on why startups slow down and fail when the founder does not use the company's own product.

LinkedIn2 min
AIMay 25, 2026

AI Arbitrage While the Window Is Open

A note arguing that AI creates a temporary arbitrage window for repeatedly trying probabilistic work that used to be closed.

LinkedIn2 min
HealthMay 25, 2026

Wanting a Complete Health Routine

A short note expressing interest in following a complete personal routine for understanding the body better.

LinkedIn1 min
AIMay 8, 2026

Why We Should Use AI

A LinkedIn note sharing a Substack essay on why using AI can be part of living more humanely, not less.

LinkedIn1 min
AI · HealthApr 14, 2026

Your New Fortune Teller Is Your Health Stack

Wearables, calendar data, and nutrition logs are starting to function like a personal operating system for life decisions. With AI agents layered on top, expert advice becomes something you can actively use rather than passively wait for.

LinkedIn2 min
AIApr 9, 2026

AI-Native Is a Phase, Agentic Business Is the Goal

I think the phrase 'AI-native company' is too broad to be the destination. It becomes clearer when we frame the destination as an agentic business and derive strategy from that future state.

LinkedIn2 min
HealthApr 1, 2026

My heart officially says I'm back

A brief personal reflection on returning.

LinkedIn1 min
HealthMar 31, 2026

My beloved Taco Bell... one soul food gone

Mourning the closure of a favorite spot, and reflecting on foods that carry comfort.

LinkedIn1 min
Engineering LeadershipMar 29, 2026

Two Dollars in My Pocket: A Founding Memory of Courage

A personal reflection on a defining moment of hardship during the early years in America - unable to afford a $2 Whopper because of tax, and how that memory of vulnerability now gives courage whenever difficult times return.

LinkedIn2 min
AIMar 25, 2026

After Going Through This, I Decided Again

After going through this, I decided again. I will delegate worry to AI, and I will keep believing, building, learning, thinking, growing, and loving. I will keep sharing Wealth + Health.

LinkedIn1 min
StartupMar 13, 2026

The Rule of Three

I used to talk about a “rule of three” in startup consulting. The fastest, easiest, and eventually cheapest path is usually the third attempt, whether it is hiring, product building, or working with coding agents.

LinkedIn2 min
AIFeb 27, 2026

Will AI Change My Role? No. I Will Live as I Always Have.

Will AI change my work and my role? No. I will keep living the way I always have. I will dream bigger, and I will do it.

LinkedIn1 min
Health · Data & Decision-MakingFeb 20, 2026

Andrej Karpathy posted his resting-heart-rate experiment on X.

Founders around me now all use Oura, Whoop, or an Apple Watch. I would bet that living like a scientist, running N=1 experiments on your own body, mind, and daily life, will become the norm.

LinkedIn2 min
HealthFeb 9, 2026

Whenever my habits start slipping, I put on a CGM and switch back into good-habits mode.

Every few months, when my lifestyle starts drifting in the wrong direction, I buy a continuous glucose monitor and use it to snap back into better habits. The new Dexcom G7 has been so off that my own glucose-prediction model performs better.

LinkedIn1 min
Video
AIFeb 7, 2026

Let AI take on more of the busywork, and live like this.

Let AI take on more of the busywork and live like this. I agree that, as of 2026, this is the highest leverage available.

LinkedIn1 min
AIFeb 5, 2026

How I use Claude Code, according to the new /insights feature.

The new /insights feature in Claude Code described me as a high-throughput power user running Claude Code as an always-on development and business-operations partner. I think that is directionally right.

LinkedIn2 min
AIFeb 3, 2026

This feels like a kind of cold-start process required to work with AI.

This preparation feels like a kind of cold start required to work with AI. Without it, you miss the coming moment of compound automation, and the gap created then will not be small.

LinkedIn1 min
Engineering LeadershipJan 28, 2026

When I ended up becoming a CTO after coming back to Korea

When I reluctantly became a CTO after returning to Korea, engineers asked me how to become better developers. I told them to widen their view of development and become strong at writing and presentations. That matters even more now because writing and presenting are distribution.

LinkedIn2 min
HealthJan 27, 2026

A study says measuring HRV before bed can predict insomnia.

A study suggests that measuring HRV before bed can predict insomnia. If breathing or meditation raises HRV before sleep, would that help? The paper is about correlation, not causation, but I want to run the n=1 experiment on myself.

LinkedIn1 min
Health · AIJan 26, 2026

These days I record every part of my personal life and intentionally live with AI’s help.

Wearables now log exercise, heart rate, and sleep 24/7, but nutrition is still the missing piece. A simple app that can analyze a food photo and push the result into Apple Health should already exist.

LinkedIn3 min
StartupJan 22, 2026

After starting a company with nothing but unreasonable confidence, the world around me changed.

When I started a company with almost nothing but sheer confidence, the people around me changed and I began to see the world differently. For a while I thought life would have been easier if I had more guidance from elders around me. That turned out to be the wrong conclusion.

LinkedIn2 min
Startup · AIJan 22, 2026

[The Era of the One-Person Unicorn Has (Really) Arrived]

Corporate operations, accounting, and paperwork are essential but painful for early startups. Taeho Kim recently automated almost the entire company-formation and operations process with AI agents and skills, excluding only one bank visit.

LinkedIn3 min
Data & Decision-MakingJan 22, 2026

1. What I look at first in a thesis defense, as a professor

In thesis defenses, the first thing I look for is always the same: what A→B hypothesis the research is actually making. That structure matters in research, in startups, and even more in the age of AI.

LinkedIn8 min
StartupJan 22, 2026

First Profit, First Giveback (Finally)

AROOO fully shifted from being community-centered to becoming a brand/product-centered business in 2025, reached KRW 3 billion in revenue, and turned profitable.

LinkedIn3 min
AIJan 18, 2026

Claude Code has been outputting ASCII tables a lot lately

Claude Code has been outputting ASCII tables a lot lately, and when Korean is mixed in, the alignment breaks because the character widths do not match. To fix that, I built a font where one Korean character is exactly twice the width of one ASCII character.

LinkedIn1 min
AIDec 25, 2025

AI can be superhuman in some domains and still lacking in others

AI has a jagged-frontier character: it is superhuman in some areas and still weak in others. If humans help clear the bottlenecks this creates, the whole system can improve dramatically.

LinkedIn1 min
Data & Decision-MakingDec 20, 2025

One lesson I love most from working with smart people

One of my favorite lessons from working with smart people is this: action creates information. If you are not sure what to do, do something anyway, even if it is wrong. That will tell you what you actually need to do.

LinkedIn1 min
AIDec 16, 2025

Development, in the old sense of adding features and fixing bugs, is over

Development, in the old sense of adding features and fixing bugs, is over. What matters now is asking boldly for what you want, pushing coding agents to ship at a standard users will pay for, and turning that into a system.

LinkedIn2 min
AIDec 9, 2025

⚠️ Biases to watch out for when using LLMs as judges

When using LLMs as evaluators, be careful about position bias, verbosity bias, and self-enhancement bias. If the generation model and the evaluation model are the same, the evaluator tends to prefer answers in its own style.

LinkedIn2 min
HealthDec 8, 2025

If you work hard because you want to do great work, your HRV drops

When I work intensely because I want to do great work, my HRV drops. I still have not found a way to work with zero stress, but if I sleep well, eat well, exercise, and spend time with good people, my resilience clearly improves.

LinkedIn1 min
Health · Data & Decision-MakingDec 2, 2025

Mirae Asset Chairman Park Hyeon-joo checks heart rate, glucose, and blood pressure for important decisions

Chairman Park Hyeon-joo reportedly checks heart rate, blood glucose, and blood pressure before major decisions so he can make them at his most rational state. I have been building and using tools like this myself, and the effect is real.

LinkedIn3 min
AINov 24, 2025

Cursor’s head of design, Ryo Lu, hints at what an AI-native company is

Ryo Lu, Cursor’s head of design, offers a strong clue for what an AI-native company is: everything is code, and the company itself is software.

LinkedIn3 min
AINov 17, 2025

These days I do not use Expo to build apps

These days I do not use Expo to build apps. Building native iOS apps with SwiftUI is easy, fast, and standard enough that the old need for cross-platform compromise is disappearing.

LinkedIn2 min
StartupNov 12, 2025

You need to choose carefully who your product is for

You need to choose carefully who your product is for, because what those people want ends up deciding the future and direction of the product.

LinkedIn2 min
AINov 6, 2025

1. The smartphone is already one of our organs.

The smartphone is already one of our organs. Humans are already delegating thought and decisions to AI, and they will delegate more and more. I plan to live inside that future for a while and see what happens.

LinkedIn1 min
Data & Decision-MakingNov 2, 2025

While designing a UI where data converges toward the right value over time

While building a UI where values arrive over time in twos, fives, and tens until they converge on the right answer, I wanted the experience to feel both friendly and sharply focused.

LinkedIn2 min
AIOct 30, 2025

As someone trained in computer science and engineering, watching how LLMs are built and work feels beautiful

As someone trained in computer science and engineering, watching the implementation and operation of LLMs gives me the feeling that they are truly beautiful. Human intelligence itself is astonishing.

LinkedIn1 min
StartupOct 29, 2025

My measure of happiness is how many happy people surround me

My measure of happiness is how many happy people surround me, and my measure of success is how many successful people surround me. Once I understood that about myself, I started intentionally engineering my surroundings.

LinkedIn3 min
HealthOct 26, 2025

The hardest person to help is the one who thinks the problem is just not knowing the right methodology

The hardest person to help is someone who thinks, 'I’m only struggling because I don’t know the right methodology, so if you just tell me the method, I’ll be fine.' The first thing that has to change is their perception of reality.

LinkedIn1 min
HealthOct 21, 2025

Sleep Is the Greatest of the Three

A reflection on the importance of sleep among the three pillars of health: exercise, diet, and sleep.

LinkedIn1 min
Engineering LeadershipOct 5, 2025

RevenueCat's 2025 App Subscription Report

The top 5% capture most of the money, day-one onboarding matters, AI and habit-forming products are strong, and retention depends more on value and timing than on price.

LinkedIn2 min
Engineering LeadershipOct 2, 2025

What an AI-Native Organization Looks Like

An AI-native organization works directly on lagging indicators like revenue, profit, and company vision, instead of optimizing the old chain of assumed prerequisite work.

LinkedIn4 min
Video
StartupOct 1, 2025

Sam Altman Takes On Zwift

Sam Altman versus Zwift. Between the Sora app and Pulse, they really do know how to build polished products.

LinkedIn1 min
AISep 30, 2025

Reusing Reasoning Steps as Behaviors

A Meta paper argues that if you define, store, and reuse the reasoning steps that recur when solving complex problems as behaviors, you can use fewer tokens and improve accuracy.

LinkedIn2 min
Video
Engineering LeadershipSep 25, 2025

What Happens When Builders Stop Thinking Like Users

This is what you get when the people making a service think like suppliers instead of users and do not even bother to dogfood the product.

LinkedIn2 min
AISep 19, 2025

Model = Simulation

To use a model is to run a small simulation of the world. I have been applying that frame to everyday life, including improving my coffee brewing with the help of an LLM.

LinkedIn3 min
AISep 19, 2025

Can LLMs Make Better VC Decisions Than Humans?

VCBench suggests LLMs may outperform humans at predicting founder success, but even if that becomes true, venture capital still depends on differentiated judgment, access, and trust.

LinkedIn2 min
Engineering LeadershipSep 7, 2025

Yang Zhilin on Managing Teams Like Training AI

Kimi founder Yang Zhilin compares team management to AI training: SFT gives direction but can suppress creativity, while RL unlocks initiative but risks reward hacking.

LinkedIn5 min
StartupSep 6, 2025

What Successful Founders Usually Say

Most successful founders I asked gave the same answer: if they had known how hard it would be, they would not have started, and they got lucky.

LinkedIn3 min
AISep 4, 2025

How to Get AI Agents to Write Code

For easy or well-known problems, coding agents usually do fine either way. For hard proprietary problems, the job is to give them enough input-output data and tell them to satisfy all of it.

LinkedIn3 min
AISep 3, 2025

Crosby and the AI-First Law Firm

Crosby is trying to reinvent contract work with AI-first operations, fixed pricing, and total turnaround time as the core metric instead of billable hours.

LinkedIn5 min
HealthSep 3, 2025

Cooking Knowledge

If cooking helped humans grow bigger brains by making food easier to digest, LLMs feel like a way to cook knowledge so we can digest it faster and use the saved time better.

LinkedIn4 min
Engineering LeadershipSep 2, 2025

Would I Be Becoming a Better Leader Without Raising Kids?

Raising children keeps teaching me that nobody is obligated to do what I say, and that understanding generational difference matters more than insisting that I am right.

LinkedIn2 min
StartupAug 29, 2025

Real Problems Take Time

"Real problems are hard, markets need explanation, and teams need time. Even the best companies take ten years to build."

LinkedIn1 min
Engineering LeadershipAug 28, 2025

Elena Verna on AI-Native Company Culture

Lovable's growth leader Elena Verna describes an AI-native organization as one where individuals own work end to end, hierarchy thins out, and AI unlocks much more creative output.

LinkedIn4 min
AIAug 23, 2025

How LLMs Help Me Win

I started using an LLM as a personal racing coach on Zwift, moving beyond raw numbers into course analysis and race strategy, and the impact has been real.

LinkedIn3 min
AIAug 22, 2025

Why Claude Code Feels Ahead of Other Coding Agents

Claude Code's edge looks less like magic and more like relentless dogfooding: Anthropic builds with it internally, tests it in real workflows, and ships what actually gets used.

LinkedIn4 min
StartupAug 22, 2025

Isn't this basically a co-founder?

If you confess both your goals and your fears, it steadies your mind. Feels worth adding to the morning routine.

LinkedIn1 min
AIAug 21, 2025

How should we interview developers now that AI can code?

If AI is part of the work, interviews should reveal whether a candidate can direct AI well, not just type code alone.

LinkedIn5 min
AIAug 20, 2025

Something unexpected happened after I opened the Harvest service I built as a hobby in English.

A small English launch triggered a tiny viral loop among students in Saudi Arabia and Iraq. If I had only looked at Korea, I never would have seen that serendipity.

LinkedIn4 min
AIAug 9, 2025

I plugged GPT-5 API into our AI products the day it launched, then turned it off behind a feature flag.

It felt too slow and underwhelming at first. Then the AMA confirmed there had been a serious incident behind the scenes.

LinkedIn4 min
Engineering LeadershipAug 6, 2025

Some people wave off what looks extraordinary to me as if it were nothing.

They're not performing humility. They genuinely think it's nothing special because they've built it routine by routine for years.

LinkedIn1 min
AIAug 6, 2025

Every time I do context engineering, I think of the senior people I worked with.

They answered nearly every question with 'It depends...' What they were really saying was: give me more context.

LinkedIn1 min
AIJul 26, 2025

Manus creates a todo file when giving an agent a complex task.

Checking items off as the work progresses reduces lost-in-the-middle and keeps the agent aligned with the goal. A lot of AI agents do this now. Humans probably should too.

LinkedIn1 min
AIJul 24, 2025

I was reading a summary of Lex Fridman's new Demis Hassabis interview.

I wanted to underline almost every line. He speaks fast, but if you keep up, he's persuasive and sharp. Intellectually overwhelming.

LinkedIn1 min
Engineering LeadershipJul 22, 2025

I spent a day vibe coding with Brian Jang from Kakao Ventures.

It was a fun session, and it left me with a few thoughts about onboarding, communication bottlenecks, and why developers may need to become founders.

LinkedIn4 min
AIJul 21, 2025

RevenueCat recently turned down a $500 million acquisition offer and instead raised a Series C at the same valuation.

The company has become a case study in capital efficiency, AI-tailwinds, and founder conviction.

LinkedIn4 min
Engineering LeadershipJul 20, 2025

I've gotten older too, and I've learned that practice doesn't always bring results.

Sometimes the process itself is what is beautiful and meaningful. A match that moved me twenty years ago surfaced again, and the athlete behind it replied.

LinkedIn2 min
Engineering LeadershipJul 20, 2025

How should we build AI products?

Don't ask users what they want. Build a product with a point of view, create something that feels magical, and focus on real adoption instead of hype.

LinkedIn2 min
Engineering LeadershipJul 17, 2025

The most loved tools

Editors and developer tools dominate the favorites list. Jira dominates the hate list. The complaints are often as much about management as they are about the tool itself.

LinkedIn2 min
Startup · AIJun 6, 2025

My Takeaways from YC Summer25 RFS

Key messages from YCombinator's Summer 2025 Requests for Startups: AI agents will deeply integrate with businesses, build the tools or build the company.

LinkedIn1 min
StartupJun 2, 2025

In San Francisco, Waymo has already passed Lyft by ride volume and is expected to pass Uber within 12 months.

What the public wanted wasn't autonomous driving technology for its own sake. It was a taxi they could ride alone, without a driver.

LinkedIn1 min
HealthMay 15, 2025

High intelligence + high energy + high consistency.

I believe that if I live this way first and surround myself with people like this, we can build a lot together.

LinkedIn1 min
Engineering LeadershipApr 22, 2025

A good tip for technical docs: explain a single concept three times.

Once in prose, once as bullet points, and once as a diagram. The tech specs that handled unfamiliar, difficult material well often felt like this.

LinkedIn1 min
StartupApr 20, 2025

Every product exists in two contexts.

There is the solution context of the product itself, and the larger context of the outcome the customer actually wants.

LinkedIn1 min
StartupApr 12, 2025

AI is the label we use for technology that hasn't quite been realized yet.

Once it works well enough, we call it machine learning. Once it becomes ordinary and ubiquitous, we just call it an algorithm.

LinkedIn2 min
Engineering LeadershipApr 8, 2025

One thing I consider personally important in work and in life is learning to see myself objectively.

Success reinforces beliefs, but beliefs are not truth. When those reinforced beliefs break, it hurts, but that pain is part of how we grow.

LinkedIn2 min
AIApr 2, 2025

I wrote this eleven years ago. Replace computers with AI agents and it becomes a story about today.

The essence has not changed. A good developer is still someone who delegates work to computers and manages them toward business impact.

LinkedIn3 min
Engineering LeadershipMar 28, 2025

Working hard vs. working smart

People who have never worked hard rarely learn how to work smart. Execution and intelligence are not opposites. They reinforce each other.

LinkedIn2 min
AIMar 24, 2025

Everything that was possible through remote work can now be done by AI.

AGI is not just about sounding smart in a text interface. It means being able to do most of what a remote knowledge worker could actually do.

LinkedIn4 min
Engineering LeadershipMar 22, 2025

Linux ships on a 9-week release cycle.

The first two weeks are a merge window for new features, and the next seven are only for fixing features and regressions. That cadence reduces pressure and improves maintainability.

LinkedIn3 min
StartupMar 22, 2025

Lately, a lot of founders from Korea have been visiting Silicon Valley.

Whenever founders ask to meet, I end up telling them the same thing: before anything else, understand how unusually specific Korea is as a business environment.

LinkedIn11 min
Engineering LeadershipMar 21, 2025

What matters most in an interview is making the other person feel, 'I'd want to work with this person.'

Once baseline competence is verified, the rest is often about rapport, curiosity, trust, and whether the conversation becomes energizing.

LinkedIn3 min
StartupMar 17, 2025

What Seth Godin says is the essence of marketing

Great marketing is not tricks or channels. It is creating something people want to talk about, then making the conditions for that idea to spread.

LinkedIn2 min
StartupMar 10, 2025

As vibe coding spreads, 2025 has become the first year in which coding is no longer a startup's main bottleneck.

When development stops being scarce, the competition shifts toward understanding customers, winning distribution, and turning AI into direct business impact.

LinkedIn4 min
Engineering LeadershipMar 2, 2025

The surest way to eliminate fear? Do the thing a hundred times.

For anything that scares you but is not life-threatening, repetition is the cleanest way to remove the fear.

LinkedIn1 min
Engineering LeadershipFeb 24, 2025

What management really is: saying clearly what is good and what is not.

To do that, you need standards, honesty, and role models. Repeating that cycle is how organizations get stronger.

LinkedIn2 min
StartupFeb 18, 2025

Japan DeNA 2025 AI Day keynote 5-line summary.

1. “We have 3,000 employees, but existing businesses will now be carried out with only half of the workforce, and the remaining half will form teams of 10 people to mass produce unicorn companies. This is possible with AI.” 2. “The West Coast of the United States already does this. We should do this too.” 3. “AI application layer collection that we are good at...

LinkedIn3 min
Data & Decision-MakingFeb 15, 2025

Just recognizing that I might be in a bad mood today can help me reduce a lot of mistakes.

I didn't feel it at all the other day, but the leading indicators were soaring that I decided to shorten the meeting without hesitation. And last night, while I was sleeping, my whole body hurt as if someone was hitting me. Fortunately, it stopped there and I recovered my condition in the morning. If I had followed the schedule as is, I probably wouldn't have ended up with a cold like I did the last time the indicator popped up.

LinkedIn1 min
Engineering LeadershipFeb 11, 2025

Differences in internal communication between Korea and the U.S. * Korea: The listener must understand on his or her own.

If communication is not good, the listener (listener) is perceived as lacking and becomes a “no sense person.” * United States: The speaker must convey clearly so that the other person can understand. When communication is poor, there is a perception that the speaker (the person speaking) needs to provide more context. Korea places responsibility on the listener...

LinkedIn2 min
HealthFeb 8, 2025

Helping startups begins with walking into their hellfire.

If you go in blindly without preparation, you will get burned as well. I don't know how to save people who are hell with others, hell with the market, and hell in their hearts. I just know that if you don't get tired, persevere, have courage, and repeat actions in a better direction, good moments will follow, so I just show this and do it together. Endure without getting tired...

LinkedIn3 min
Data & Decision-MakingFeb 5, 2025

Dub: A copy trading app that has become a hot topic among American teenagers * Copy trading: Trading other investors’ portfolios…

Dub: A copy trading app that has become a hot topic among American teenagers * Copy trading: An investment method that copies another investor’s portfolio. 1. Dub’s core idea is “choosing people, not stocks.” In other words, you can copy the investment strategies of traders, hedge funds, or celebrities, rather than individual stocks...

LinkedIn5 min
StartupJan 30, 2025

3 ways startup CEOs break up their teams and ruin their businesses.

1. Say different things to each person you meet. - A CEO’s leadership comes from consistency. As the organization grows, it becomes more important. - Don’t think of something as A, but tell the developer it’s B, the designer it’s C, and the investor it’s D. If you ask me later why I did that, things will work out...

LinkedIn4 min
AIJan 27, 2025

1. Recently, generative AI, especially LLM (Large

As I meet startups that use e Language Model, I often worry about how to develop and improve AI. Many teams are still accustomed to the traditional “deterministic” approach to software development and are often faced with challenges when working on AI projects. 2....

LinkedIn7 min
StartupJan 16, 2025

For about a month, I posted long and short articles on LinkedIn, Threads, Substack, and Facebook.

About what I felt. 1. LinkedIn: I generally get a good response, probably because the topics I write are related to startups and careers. The post sharing things I learned at my previous job, including Coupang, received 1,000 likes in just a few days even though I didn't have many LinkedIn friends. 2. Threads: First posts...

LinkedIn2 min
StartupJan 14, 2025

Four “rules of the early startup game” that are obvious if you know them, but are expensive if you don’t know them.

1. The essence of invested startups is growth and expansion. - From Seed Investment -> Pre-Series A -> Series A -> Series B, there must be 10x growth in key indicators such as sales or active users, or expansion to support this. - Just because time passes and you run out of money doesn't mean you move on....

LinkedIn10 min
Engineering LeadershipJan 12, 2025

What is leadership?

? As you build your career, the world demands a greater impact. A big impact cannot be made by staying up all night alone. It can only be made with more people and over a longer period of time. Creating a greater impact by spending more time with more people is called ‘leadership.’

LinkedIn1 min
StartupJan 7, 2025

The Intro Post I Shared When I Started Working with Kakao Ventures

I like building things, but I only consider them truly alive when people actually use them. My path has taken me from founding a startup in the U.S. to seeing companies across Korea and the U.S. at many different stages, and that accumulated experience is what I hope to bring into this EIR role.

LinkedIn3 min
AIJan 3, 2025

Types of Sinister Pivots - Andrew Chen 1.

Transition from B2B to B2C. “Going from a B2B with networks and expertise to a consumer is like asking a soccer player to suddenly do ballet.” 2. Add chat/social/notification functions. “If people don’t love your product, you can send them 100 notifications and they’ll still be indifferent...

LinkedIn3 min
Data & Decision-MakingDec 30, 2024

One way North Korea steals cryptocurrency.

1. Approach the job seeker on LinkedIn and download the repository called coinbase2024/voting-dapp from Bitbucket in the name of an assignment. 2. Malware is hidden in the test file of one of these codes, so when the developer runs the test case, the malware is activated. 3. At this time, activate...

LinkedIn3 min
Engineering LeadershipDec 28, 2024

After leaving Coupang and working at other Korean startups, there was one question I always had.

“As a company grows, large and small interests and conflicts between the upper and lower levels, as well as between each organization, become rampant and the growth rate slows down. Why did Coupang not become like this and was it possible to minimize this?” Although I suddenly realized it later, I dare to believe that Coupang’s interpreters made this possible. Coupang...

LinkedIn5 min
Data & Decision-MakingDec 27, 2024

“Talent = Good Taste + Bridging Effort” 1.

Good taste is the ability to distinguish “what is good” and the ability to set the right direction when doing something. 2. People with good taste tend to have a gap between reality and standards, and the effort to bridge this gap is the second element of talent. 3. Many people struggle between reality and ideals...

LinkedIn2 min
Data & Decision-MakingDec 25, 2024

How to measure threaded iOS app performance (Source: Meta Engineering Blog) 1.

The premise of Thread iOS app performance standards is to provide the best user experience. To achieve this, the app must be fast and outstanding, and the following performance metrics are selected and used. 2. %FIRE (Frustrating Image-Render Experience): Percentage of frustrating image-rendering experience. fury...

LinkedIn5 min
StartupDec 24, 2024

It is not for nothing that people and teams are said to be invested in.

1. Startups fail not when they run out of money, but when the CEO gives up. 2. The investment was made to hit the ground running, but if the co-founders start fighting with each other just because they have a little bit of free time, the team's time and energy will be wasted in coordinating this process. 3. Important things in the world are not on the Internet. You have to go out and find it. This is nothing but people...

LinkedIn1 min
StartupDec 22, 2024

Product-Market Fit is like, at some point, “Now we’ve got it!” It sounds like it's over, but the truth is...

Product-Market Fit is like, at some point, “Now we’ve got it!” It sounds like it's over and done with, but in reality, it's a concept that needs to be constantly measured and explored throughout the entire startup process. If you are an early startup and do not have data such as NPS or retention yet, approach the next step. 1. Founder-Problem Fi...

LinkedIn3 min
Engineering LeadershipDec 21, 2024

User-centered engineering - Improving the user experience should be the goal of engineering.

1. Let’s ask questions before writing code. “Who is this product for?”, “What problem are we really trying to solve?”, “What do users want?” 2. Let’s ask questions during development. “Does this feature simplify the user’s workflow?”, “Is this feature intuitive?”, “Make this better...

LinkedIn4 min
AIDec 20, 2024

Changes in the app market: Downloads decrease, profits increase 1.

In 2024, app downloads decreased by 2.3% and remained at 110 billion. However, users spend $127 billion on apps. This is a 15.7% increase compared to the previous year, and this growth is especially driven by the Apple App Store. 2. App downloads decreased for both iOS (-1.1%) and Android (-2.6%), but...

LinkedIn4 min
HealthDec 19, 2024

1. As a result of analyzing occupational groups in the United States, taxi drivers and

Ambulance drivers have the lowest risk of dying from Alzheimer's disease among all occupations. Taxi drivers were 1.03% and ambulance drivers were 0.91%, which is significantly lower than the average for general occupations of 1.69%. 2. Taxi and ambulance drivers repeatedly navigate complex routes and make immediate decisions in real time every day. This and...

LinkedIn3 min
Data & Decision-MakingDec 18, 2024

MIT researchers reveal why legal documents are difficult.

1. MIT’s cognitive science research team focused on “Why are legal documents so difficult to read?” After research, they came to an unexpected conclusion: complexity in legal documents is not a simple mistake, but a “device for expressing authority.” 2. Professor Edward Gibson's research team found that the language of legal documents was like a magic spell...

LinkedIn5 min
Engineering LeadershipDec 17, 2024

Analysis of OpenAI's latest failure report OpenAI released a public report on failures that occurred on December 11th.

This report details the causes and resolution of system failures, so there is a lot to learn from it. 1. System Overload (Saturation) - The Beginning of Failure "With thousands of nodes performing tasks simultaneously, the Kubernetes API server became overloaded, which was the case in most large clusters...

LinkedIn9 min
AIDec 15, 2024

The AI ​​development stage resembles the leader's delegation expansion stage.

1. The initial GPT was at the level of a chatbot, answering questions. At this time, people made and executed all decisions themselves, so it was rarely left to AI. 2. An LLM with reasoning skills goes beyond simply providing information and helps with decision-making. For example, if you ask “how should I spend my budget,” AI...

LinkedIn3 min
AIDec 14, 2024

1. The most surprising thing now is that in just 24 months

1. “The most amazing thing now is that you can start a company that generates tens of millions of dollars in just 24 months, and it can be done for as little as $2 to $5 million.” 2. "YC startups in 2024 saw their sales triple within 10 weeks on average, and in the past, the top...

LinkedIn4 min
Engineering LeadershipDec 12, 2024

If someone is criticizing someone else, be happy to say it.

“Ah, now we’re in the problem-solving phase.” Andy Grove says in 'High Output Management' that if someone is blaming others, they have moved beyond ignoring or denying the problem to understanding the problem. Only through this process can responsibility be acknowledged and a solution found. So the manager is a member of the team...

LinkedIn2 min
StartupDec 11, 2024

This process is the same for not only thesis but also starting a business.

“The real ability is not the ability to find items or a flash of genius in marketing or development, but the endurance to do something even if you don’t want to, the audacity to throw even a low-quality prototype and the resilience to stand up and say, ‘Lucky Vicky!’ when you get bad feedback. This is what helps you win a long-term battle.” If you exaggerate, you can achieve results other than this...

LinkedIn2 min
Engineering LeadershipDec 10, 2024

Japanese web design: strange but effective.

Why? 1. Japanese websites tend to pack a variety of information and elements on one screen. Rather than simply reducing the composition like the American site, even services with the same purpose show much more text and images at the same time. This goes beyond differences in aesthetic tastes and stems from Japanese cultural/psychological characteristics. 2. Japanese history...

LinkedIn10 min