FAQ (1 of 2)

What is a Product Build Day? A one-day hackathon for product people who do not write code. Up to eight people build working prototypes with AI tools against one challenge, real users react the same afternoon, every team pitches, and the most senior person in the room decides before anyone leaves. One day in, one decision out.

How is it different from a design sprint? Mostly in what changed underneath both: building got cheap. The sprint gives a week and has one designer build one facade prototype. A build day gives one day and has everyone build real working prototypes, because vibe coding lets the whole room build. Both put a decider in the room and let a real user settle the call. I love the sprint. This is what I run when the question deserves a day, not a week.

Is it a hackathon? Yes, the smallest honest kind. No stage, no sponsors, no 200 people. Eight people, one room, one decision. If you are trying to run the 200-person kind, this is the wrong book.

Who should be in the room? The people who decide what gets built and the people who quietly shape those decisions: PM, designer, marketing or sales, a subject matter expert, often a developer. Leadership joins for the last hour to decide. Chapter 8 has the full table.

Do we need developers? No. The AI tools do the typing. Bring a developer anyway if you can: they often build fastest, and a developer who has watched a salesperson ship a working screen goes home with a different view of the company.

What tools do we use? Lovable, Bolt.new, or Replit, or whatever does the same trick the month you read this; v0 and Claude's artifacts also qualify. Pick one default and move on. The question is worth thirty seconds, and Chapter 12 spends exactly that on it.