Dear founders,
Golden Section runs on institutional memory. We are deliberate about mistakes — we document them, we learn from them, and we go looking for the next one. That habit is the substance of our partnership with our portfolio, not a slogan about it.
The habit produces two things: a numbered list of mistakes, and the plays that prevent them. Today that is 161 mistakes and 63 plays, with 59 working templates attached. Every mistake is paired to the play that prevents it. All of it came from watching more than 400 B2B software companies over more than a decade.
We have run these plays with founders for years, and shared them widely. Sharing is not the same as handing something over. You could read what we gave you. You could not take it, fork it, correct it, or build something of your own on top of it — because we never actually gave you the right to. Today we do, and we are doing it in a way you can work on alongside us. The whole corpus is here on this site and in a public repository, under a Creative Commons license: yours to copy, adapt, and use commercially, including in ways we would not have thought of.
What changed is the pace. AI is compressing the loop between a conversation with a founder and a codified play. We expect this list to grow faster and get more granular in the next year than it has in ten years of doing it by hand. A playbook that used to change quarterly can now change weekly.
That speed is the opportunity and the risk in one sentence. Version velocity plus AI produces either collective genius or collective slop, and the whole difference is who reviews what gets merged. So there is a human gate: every change is read by a person before it lands, and every claim has to come from something that actually happened to somebody. We would rather move slower and stay true.
We want company in this. Founders, funds, and advisors willing to shepherd it — argue with an entry, add the mistake we have not made yet, fix a formula in a template, or tell us a play did not work. Especially that last one.
This is not altruism and we would rather not pretend it is. We expect to use whatever the collective produces, in our own execution, with our own companies. We can say that plainly because knowledge stopped being the differentiator a while ago. What differentiates now is relationships and execution, and both get stronger as the shared base gets better. There is no version of this where we lose by everyone knowing more.
Our commitment: we keep putting real applications and real outcomes back in, including the ones that did not work. We invite you to do the same.
Start here. Read the mistakes list, end to end. It takes twenty minutes and you will find three things happening in your company right now.