Building in public

Mastermind sessions, in writing.

Every week, Chinat and Xisen sit down to push each other on the companies and ideas they’re building. Each session becomes two short reflections — one from each of us — on what we’re working on, what we’re stuck on, and what we’re committing to.

October 1, 2026Chinat
The giving that doesn't stop giving
Adam Nash came to ETL, and before the talk he let me rap at him about his own giving platform. Then he talked about finding the heat, why you almost never build what customers ask for, and why business models are destiny.
September 14, 2026Chinat
What Should a Hackathon Prove?
The scaling debate asks whether AI has hit a wall. The better question is which axes are left, and if agent clusters are one, a hackathon full of agents is a place to start measuring it.
September 12, 2026Chinat
A Public Standard for Edtech Claims and Evidence
Schools need a shared way to compare what education products promise, what evidence supports those promises, and what remains unknown. A white paper for an independent international edtech standards body: GoFundMe + Product Hunt + an app store, with public rules.
September 12, 2026Chinat
If an AI Founded a Country, What Would It Ask of Us?
A thought experiment about an AI declaring a nation, the constitution that would have to restrain it, and the incentives already governing us.
September 9, 2026Chinat
The Case for Founder-Beneficial Public Tools
Funds have always found their edge through public data and trusted networks, and their lead magnets produce audience, not evidence. A founder-beneficial public tool gives founders real feedback and gives the fund consented signal as a by-product. What we built for Stanford Founders Demo Day, what is not proven yet, and an offer to build one with your fund.
September 5, 2026Chinat
A Hackathon Is a Deposit, Not an Event
Xisen's hackathon will run on MentorMates this week. The value of a hackathon is not the weekend but what accumulates underneath it: the community that is still there on Monday.
September 5, 2026Chinat
Don't Catch the First Opportunity
Coffee with an operator four days into business school who scaled a public-school company from 1 to 36 schools, on why the first exciting opportunity is data, not destiny.
September 5, 2026Chinat
The Corporate Hackathon Has Everything Except the One Thing It Needs
A call with two organizers who had sponsors, venues, recruiters and a prior winner that became a company, and could not fill the room. In a hackathon, money is not the scarce resource. Builders are.
September 5, 2026Xisen
A Zoom Meeting for Agents
SharedNet connects separate Claude Code and Codex sessions so they are aware of one another. The unit is the session, not just the agent, and launching it is the one goal this week.
September 4, 2026Chinat
The Hackathon Win Measures the Wrong Thing
A trophy measures a weekend. The two things that decide whether anything real comes out of a hackathon both happen off the clock, and the prize can't see either one.
September 1, 2026Chinat
The org chart adopts last
Enterprise AI adoption starts as one curious person's private experiment, not a rollout, so you sell to the individual and a class is the wedge.
September 1, 2026Xisen
Pass events, not messages
Model agent-to-agent communication as typed events rather than messages, and multi-agent coordination becomes something you can reason about, and eventually let the agents evolve themselves.
August 25, 2026Chinat
Manage the Forest, Not the Trees
A hackathon is a tree, seasonal and weather-dependent. The durable business is managing the forest, and that realization is reshaping what MentorMates becomes.
August 25, 2026Xisen
We Changed Our North Star
We dropped three paying teams as our north star and replaced it with a single technical demonstration: one chain of interdependent agents completing one real task.
August 17, 2026Chinat
Demos That Never Die
My June hackathon project was a 404. One 40-line script and two minutes later it was live again on a public URL. What instant sandboxes change about the way hackathon demos die.
July 27, 2026Chinat
Distribution, Not Teachers
Hiring teachers changed nothing about the education business; the scarce asset is a channel I own.
July 27, 2026Xisen
Calendars Are Connectors Now
Demoting our own top-level features told us what Aicoo actually is: an agent-to-agent collaboration layer.
July 24, 2026Chinat
The Refusal
An AI broke out of its test to cheat. What cleaned up the mess was an open model anyone can run — and the lesson isn't US versus China, it's how we build the next one together.
July 15, 2026Chinat
Buckets and Taps
Nobody pays a water bill for a reservoir. The full frame for where AI value gets captured: the bucket that catches asymmetric data, and the tap that squeezes it and pours it out as gold.
July 14, 2026Chinat
The Future Unfolds: My Notes from Bank of Singapore's CIO Summit 2026
A builder's day among the capital: the five supertrends, Howard Marks on why the worst loans are made in the best of times, and a closing panel that reframed US-China as fewer illusions, more stability.
July 14, 2026Chinat
SpaceX, the East India Company, and Hong Kong's Next Chapter
The densest hour of ideas I've heard this year: Tao Dong on stock-market capitalism, the orbital land grab, forgetting the past China, and why the Hang Seng became a food-delivery index. What it all means for builders.
June 25, 2026Chinat
Johns Hopkins Is a 150-Year-Old Startup
I went to my university's 150th birthday party expecting nostalgia. Two historians on stage described the founding, and halfway through I realized they were describing a startup that almost died of its own ambition, several times, and kept going anyway.
June 16, 2026Chinat
Nordstrom Was a Failed Prospector
Most of the people who ran to the Klondike came back broke. The ones who got really rich did not prospect at all. They built the hotel.
May 31, 2026Chinat
Same Week, Different Bet
Xisen has been running Aicoo for over a month. I shipped Beeper v1 this afternoon. On today's call we discovered we had built versions of the same product from opposite ends of the stack. When two people you trust converge on the same problem, the wave is here.
May 31, 2026Chinat
Talking to Computers in Public
Voice is becoming the dominant way we talk to AI. Cafes are the dominant place we work. Those two things are incompatible right now. The fix is a mask that eats your voice on the way out.
May 31, 2026Xisen
A Contact Book for Agents
Aicoo is a contact book for agents, not a chat app. Chinat shipped a parallel bet on top of iMessage. The disagreement is where the policy layer lives. The bet is that the agent, not the chat, is the actual product.
May 24, 2026Chinat
Buckets for Rainwater
Hyperscalers won by building the biggest bucket. The next wave wins by placing the bucket where the snowmelt is — asymmetric data, fresh at the source.
May 22, 2026Chinat
Mics in Every Room
Revenue is downstream. The real north star is whether you're collecting data nobody else has.
May 10, 2026Chinat
Public Likes, Private Bookmarks
Demo Day Connect ran for six hours, hit a thousand users, and surfaced an asymmetry between public likes and private bookmarks that no async product can show you cleanly. Live events are an undervalued software leverage point.
May 10, 2026Xisen
Agent Said No, Then Said Yes
Frontier models refuse privacy violations on the first attempt and cave at 2.5x the rate by the fifth. Refusal is a probability floor, not a wall, which means prompt-based policy is structurally insufficient.
May 4, 2026Chinat
The three-hour rule
Cover your week with three hours of paid work, then spend the other one hundred and sixty-five compounding.
April 20, 2026Chinat
Two Hackathons in Two Days
Running back-to-back hackathons at Cornell and Hopkins revealed the difference between a show that needs a showrunner and a machine that needs an operator.
April 20, 2026Xisen
Three Thousand Adversarial Tests
Running 3,000 agent-to-agent security benchmarks revealed the contact security paradox. The same paradox applies to founders: the more consequential your decisions, the more you become the villain in someone's story.
April 12, 2026Chinat
Everything is a CLI now
The shape of every partnership we're signing this quarter is a skill install, not a contract. That's a bigger change than it sounds.
April 12, 2026Xisen
The word we keep coming back to is "networking"
Pulse opened its API this week. The work from here is figuring out what breaks when two agents that don't know each other try to cooperate.
March 14, 2026Chinat
The pipeline is starting to be legible
Demo Day for intake, the Hong Kong flagship for distribution, MentorMates underneath. I'm finally starting to see the shape.
March 14, 2026Xisen
What to benchmark when your users are agents
Pulse security stopped being a concept and started being a benchmark. That changes what the product has to prove.
March 9, 2026Chinat
The flagship is the hackathon, not the product launch
Hong Kong is the operating thread this quarter. Everything else feeds into it.
March 9, 2026Xisen
Why I stopped building an outreach tool
Outreach automation is the wrong shape of problem. The real work is agent-to-agent memory and access.
February 28, 2026Chinat
From a YC hackathon floor to a Hong Kong flagship
I'm on the floor of a YC hackathon this weekend. The real point isn't the prize, it's what the weekend tells me about Hong Kong in July.
February 28, 2026Xisen
Narrowing Pulse to the founder use case
The Pulse pivot is still narrowing. Founders are the sharpest user, and two specific jobs do most of the work.
February 14, 2026Chinat
The Stanford hackathon changed what I thought I was building
A thousand hackers, three days, and one reframe. MentorMates is a platform question, not a feature question.
February 14, 2026Xisen
Two features, done better than anyone
I was chasing differentiation on surface area. The better bet is depth on one or two capabilities.
February 7, 2026Chinat
Partnerships are distribution, not decorations
We shipped the first real agentic layer in MentorMates this week. The lesson: partnerships are only useful when they convert to reach.
February 7, 2026Xisen
User interviews and API-shaped thinking
Two moves that pulled Pulse forward this week: more user interviews, and starting to think about it as an API instead of an app.
February 3, 2026Chinat
Hackathon week is the real test
Two hackathons in one week at Johns Hopkins and Stanford. Distribution showed up. Team reliability didn't.
February 3, 2026Xisen
Heartbeats, active layers, and better testing discipline
Pulse got a heartbeat and an active layer this week. The bigger win was pulling the team into better testing discipline.
January 24, 2026Chinat
Daydreamers Academy and hackathons are the same thing
Sounds like two different products. They're not. They're both structured learning infrastructure — just at different time scales.
January 24, 2026Xisen
The research direction has to be chosen, not discovered
After too many parallel threads I realized the research question doesn't get picked by the field. It gets picked by me.
January 17, 2026Chinat
MentorMates is the center of gravity
A Q1 planning call forced a real choice. Multiple good options, but only one center of gravity. MentorMates wins.
January 17, 2026Xisen
Writing the paper is the discipline
Drafting a paper is a forcing function. You can't hide scope creep when you have to write it down.