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.
Kept light, but real
Researchers who study founders keep finding the same thing.
Studies that track startups for years find co-founder conflict is one of the top reasons they fail, often ahead of the product or the market. Some researchers half-jokingly compare the co-founder breakup rate to divorce. The difference: you don't even get a wedding.
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
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.
A real company, at exactly this stage
Apple was two people in a garage who sharpened each other.
Jobs could not build what Wozniak built. Wozniak would never have sold what Jobs sold. Neither one alone becomes Apple. The pattern you are choosing for this afternoon is the same one.
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
Builder
You might be this if...
▸ you'd rather build the wrong thing than talk about the right thing
▸ you've taken a broken remote apart just to see what's inside
▸ you've modded a game or broken a Roblox script on purpose, then fixed it
Designer
You might be this if...
▸ you rearrange furniture, playlists, or your phone's home screen for fun
▸ you notice when the spacing is off before you notice what the text says
▸ you've rebuilt a Notion page or a slide deck three times just because
Storyteller
You might be this if...
▸ you're the one who explains the group project to the teacher
▸ you write the caption everyone else just wants to repost
▸ you can make a genuinely 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
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 closedSkill + style card
5:00 on the clock
1Card: your name, your strongest role (builder / designer / storyteller).
2Add one line: "I work best when…" (quiet/loud, plan/improvise, morning/deadline).
3Post it 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 25 builders and 3 storytellers has a math problem. Better to see it before the draft than during it.
Now it gets real
Your thesis meets the whole room.
6 rounds, 4 minutes each. Pitching a stranger fast is a founder skill you will use for the rest of your life, not just today.
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
1~90 seconds: pitch your thesis. ~90 seconds: hear theirs.
2~60 seconds: score them, they score you, on the one question.
3Bell rings this timer again for the next partner. Reuse it 6 times.
4:00
Bell · rotate, repeat
When the bell rings
Rotate immediately. No lingering conversations.
Move clockwise to the next open partner. Your note stays with you, not with them. No overtime, even mid-sentence. All 6 rounds run back to back.
Look at your notes
2 or 3 names keep coming up. That's not luck.
That's signal. Those are the people who made your thinking better six times out of six chances.
The draft
The room chooses its strongest theses.
Not every thesis survives to become a team. That's the point. It's a filter, not a punishment.
Exercise 3 · do it now
OFFLINE · screens closedThe draft
10:00 on the clock
1Strongest theses (your top-3 names from speed-dating) stand up front.
2Form teams of 2 or 3: one thesis, complementary roles.
3No team of three builders. No team without a storyteller.
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.
The team contract, one slide
Five lines that save your week
Roles
One name owns each area. 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.
Line worth slowing down for
Roles
Too vague
"we're all just kind of doing everything together!"
Actually usable
Mei owns build. Priya owns design. Zhou 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 · do it now
OFFLINE · screens closedWrite your contract
5:00 on the clock
1Fill in your 5 lines. One sentence each, no essays.
2Every person signs it. Literally, pen on paper.
3Do not post it yet. It gets stress-tested first.
5:00
Then: stress-test it
Copy this prompt · run it now
Stress-test it
Here is our 5-line team contract. Play out three realistic conflict scenarios for a student startup team this week (disagreement on scope, one member overloaded, deadline pressure at 4pm) and show where our contract breaks. Suggest one fix per hole.
Exercise 5 · do it now
OFFLINE · screens closedRun it, patch the holes
5:00 on the clock
1Paste your contract and the prompt into Claude.
2Read the three scenarios out loud as a team. Wince where it's true.
3Patch each hole with one added sentence, right on the sheet.
5:00
Then: THE WALL
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
quick watch
Short and clear: what actually predicts a good co-founder match. Same idea as today's speed-dating rounds.
youtube.com/watch?v=Fk9BCr5pLTU
For the ambitious: the deeper dive
long watch
A longer YC partner talk on choosing a co-founder, for anyone who wants the full version after this week.
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.