You first
Hands up: who already knows who they're building with?
▸ click to reveal after they answer
Some of you are about to find out that's not the right person. That's completely fine. The next 75 minutes exist to fix exactly that, on purpose, before it costs you anything.
Not luck, mechanics
Nobody plans to fight. Undefined teams do it for them.
No one decided who makes the final call. No one agreed what happens when you disagree. No one planned for the day someone stops replying. Add a real deadline and two people who never wrote any of that down, and conflict isn't bad luck. It's the default setting. You're about to write it down on purpose, before reality does it for you.
You first
Should you just team up with your best friend?
▸ click to reveal after they answer
Only if your best friend sharpens your thinking. You are choosing a co-founder, not a seatmate. Watch who makes your idea better, not who makes you laugh hardest.
The friends-only trap
Your group chat is not your company
In forty minutes there are three rules that make this easy, so you don't have to trust your gut alone.
The group chat
same jokes, same opinions, nobody wants to be the one who says "actually I think this is a bad idea." project quietly dies by day 3.
The company
different instincts, someone always finds the hole in the plan, disagreement is normal, and the idea survives contact with reality.
So what do you look for instead?
Complementary means different, not identical.
You are not hunting for a clone of yourself. You are hunting for the person who is strong exactly where you are weak.
YOU FIRST · I'm calling on someone
Match the duo
One soldered a computer in a garage. The other convinced the world it mattered.
▸ reveal
Steve Jobs and Steve Wozniak, Apple.
They flipped a coin for whose name went first.
▸ reveal
Bill Hewlett and Dave Packard, HP. Remember this one, it comes back when we talk about whose name goes first.
Childhood friends. It worked because one owned the ice cream and one owned the business.
▸ reveal
Ben Cohen and Jerry Greenfield, Ben and Jerry's. Friends can work, when the roles are real.
They argued constantly, and said the arguing was the point.
▸ reveal
Larry Page and Sergey Brin, Google.
You already named this one
The garage was real. Here is what each of them actually did in it.
Wozniak designed and hand-built the circuit board himself, nights after his day job at HP. Jobs had never written a line of code. He talked a local store into ordering fifty of them before there was a company to deliver them. Neither move works without the other. The pattern you are choosing this afternoon is the same one.
Hands up
In your future team, are you the Wozniak or the Jobs?
Wozniak builds it. Jobs sells it. No wrong answer, just remember which hand you raised. The skill cards are next.
Roles
Three roles, one shape
Builder
Owns the tool, the code, the deploy
Designer
Owns how it looks and feels
Storyteller
Owns words, users, the pitch
Every team needs all three
Which one are you
You already know. You've just never named it.
Builder
You'd rather build the wrong thing than talk about the right thing. You've taken something apart just to see what's inside.
Designer
You notice bad spacing before you notice what the text says. You've rebuilt the same slide three times, just because.
Storyteller
You're the one who explains the group project to the teacher. You can make a boring topic sound like it matters.
You first
Should your co-founder work exactly like you?
▸ click to reveal after they answer
No. You want someone who covers your blind spot: planners with improvisers, morning people with deadline crammers, quiet processors with loud thinkers.
Work style, not skill
Nobody's wrong here, just different
Planner ↔ Improviser
Maps every step first vs. starts typing and figures it out along the way
Morning ↔ Deadline
Sharpest at 8am vs. sharpest at 11:58pm the night before
Quiet ↔ Loud
Needs silence to think vs. thinks out loud, mid-sentence, at volume
YOU FIRST · I'm calling on someone
Your teammate says "the plan just died." What does a resourceful co-founder say next?
▸ click to reveal after they answer
Not "guess we're done." Something like "who else could we ask" or "fine, we build it without that piece." Paul Graham, Y Combinator: relentlessly resourceful is the single trait YC actually selects founders for. A co-founder who finds a way beats one who finds a reason, every time.
The upgrade
A team of two identical people is one person with a louder voice.
Pick friction on purpose, now. It is much cheaper today than it is in week 3 of building.
Exercise 1 · do it now
OFFLINE · screens closedFounder card
5:00 on the clock
1Your name.
2The thing you're proudest of making or doing. Anything counts: a video, a team, a grade comeback, a game mod.
3Your hobbies and obsessions, one line.
4The thing you're weirdly good at.
5Your role instinct: builder / designer / storyteller. Post the card on the role board.
5:00
Then: THE WALL, sorted by role
Look at the wall
If it's mostly one column, know that now.
A room with 8 builders and 1 storyteller has a math problem. Better to see it before the draft than during it.
Same 4 minutes, two outcomes
What good sounds like
Just nice
"oh that's such a good idea, I'd totally use that!"
Actually sharpens
"would people actually pay for that, or just say they would? how would you tell the difference?"
Exercise 2 · do it now
OFFLINE · screens closedFounder speed-dating, round timer
4:00 per round · run ×6
1~30 seconds: trade founder cards. Proudest thing, plus one hobby. You're choosing a person, not just an idea.
2~75 seconds: pitch your thesis. ~75 seconds: hear theirs.
3~60 seconds: score them, they score you, on the one question.
4Bell rings? Rotate immediately, no lingering, no finishing the sentence. Reuse this timer 6 times.
4:00
Bell · rotate, repeat
Look at your notes
2 or 3 names keep coming up. That's not luck.
That's signal. Those are the people who argued with you, made you defend it, and made it sharper, six rounds out of six.
Exercise 3 · do it now
OFFLINE · screens closedThe draft
10:00 on the clock
1
Walk to the wall, sign under your problem
Pen, public. Sign under the surviving problem on the wall you believe in most.
2
Look at who signed with you
Check the two rules: at least two different role cards, and at least one person you met for the first time today.
3
If a rule fails, fix it now
Someone trades to their second-choice problem. No debate, just a trade.
4
Ties and rule-breaks: Phillip decides, with your scorecards
The person who sharpened your thesis most in speed-dating is the teammate you want. The scores are the tiebreaker, not friendship.
10:00
Teams stand together
If you're standing together
That's your team. One thesis, roles claimed.
You'll spend four more days with these exact people. Next: make sure it actually works on day 3, not just today.
Titles, not just roles
From this moment, you're not "the builder." You're the CTO.
Builder
CTO
Designer
CPO
Storyteller
CEO
Team of two? One of you holds two titles, write both down. Introduce yourself this way at standup starting now. It goes on the contract, and on Sunday the judges hear it.
The team contract, one slide
Five lines that save your week
Roles + titles
One name owns each area, with a title: CTO, CPO, CEO. Anyone can help anywhere.
Decision rule
Can't agree in 10 minutes? The owner decides. Written down.
When stuck
Stuck 20+ minutes? Say so out loud. Nobody suffers silently.
Our hours
Check in 9am and 4pm. Offline 2+ hours? Say why, in advance.
What DONE means
Live at a real URL. A stranger can use it without us explaining.
John Lennon and Paul McCartney wrote better songs arguing than either wrote alone. That's why your contract has a disagreement rule.
Line worth slowing down for
Roles + titles
Too vague
"we're all just kind of doing everything together!"
Actually usable
Mei, CTO: owns build. Priya, CPO: owns design. Zhou, CEO: owns story. Anyone can help anywhere, but one name owns each area.
And the one that decides ship day
What DONE means
Too vague
"it's basically done, just needs a few small tweaks"
Actually usable
Done means live at a real URL, and a stranger can use it without us standing there explaining.
Exercise 4 · the contract forge
FOLLOW ALONG · laptops openThe contract forge
15:00 on the clock
Win condition: it does not go on the wall until every hole Claude finds is patched. All three, not just the easy one.
1
Write the 5 lines
Line 1 pairs each name with a title, e.g. "Jean Chen, CTO: owns the build." Then decision rule, disagreement rule, hours, definition of done. One sentence each. Minimum: all 5 filled by minute 5.
2
Stress-test it in Claude
Paste your contract and this prompt. Minimum: all three scenarios run by minute 10.
Here is our 5-line team contract. Play out three brutal scenarios: a scope fight at 4pm, one member checked out for the day, and deadline panic the night before we ship. Show exactly where our contract breaks in each one. One concrete fix per hole, nothing vague.
3
Patch every hole, then sign and post
One added sentence per hole, right on the sheet. Every person signs. Post only once all three are patched.
15:00
Then: THE WALL, holes patched
Debrief, once
Say your sharpest patch out loud.
Whichever scenario broke your contract hardest is the line you needed most. That's the exercise working, not a failure. Now it goes on the wall.
You first
Whose name goes first?
▸ click to reveal after they answer
Nobody's, by default, until you're standing in front of people and someone has to open their mouth first. Decide now: who presents, whose name leads, how credit splits when only one of you gets asked about it afterward. Not because it's fair this second. Because arguing about it under pressure is worse.
Go deeper · optional
This exists for grown-up founders too
YC's actual co-founder matching site
2 min browse
Real adult founders use this exact platform to find a co-founder online. You just did the in-person version, for free, in 75 minutes.
ycombinator.com/cofounder-matching
How to find a co-founder, from YC itself
~30 min
What actually predicts a good co-founder match. Same idea as today's speed-dating rounds. Tonight's watch, not a class video, it runs about 30 minutes.
youtube.com/watch?v=Fk9BCr5pLTU
For the ambitious: the deeper dive
~40 min
A longer YC partner talk on choosing a co-founder, for anyone who wants the full version after this week. About 40 minutes, save it for home.
youtube.com/watch?v=prKi3-rUPHc
All three are on the portal too.
Last thing · two minutes FOLLOW ALONG · laptops open
Every company needs a battle cry.
Paste your team name and contract into Claude: “give us five team mottos, funny allowed.” Pick one. Write it on the contract, under the signatures. This is now legally binding team spirit.