Building Your Founding Team — Lesson 8: Two Weeks Before the Handshake

This is The Build Log, the weekly startup-fundamentals series from The AI-Native Founder. New here? Start with Lesson 1.

It is Tuesday night and you have had your third good call with someone you met through a co-founder matching site. They are sharp, they like the problem, and on the last call they asked how you think about equity. You liked them more after every call. You also realise you have never seen them work: not one deadline, not one disagreement, not one week where something had to be cut.

This lesson is about getting that evidence before the handshake. You leave with trial.md, a two-week trial brief built from the handover.md you wrote last week, and a review prompt that reads the trial’s own record and tells you what the two of you actually did when you disagreed.