Product Market Fit

Product Market Fit

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The Startup Security Audit with Claude

The Hands-On Playbook to Find the Security Holes in Your Startup Before Someone Else Does

Guillermo Flor's avatar
Guillermo Flor
Sep 04, 2026
∙ Paid

BREAKING: Palo Alto’s CEO just called a trillion dollars of enterprise security infrastructure OBSOLETE

His argument is that systems deployed seven to ten years ago were built for a threat environment that no longer exists, that AI-powered attacks now run at machine speed, and that the gap is structural rather than a patching problem (👉 Full Post Here).

That is a CISO’s problem. Here is the same shift at founder scale.

The attacks that reach an eight-person company were always the cheap ones: phishing, credential stuffing, keys harvested from public repos. What changed is that running them now costs almost nothing, so they get pointed at everyone instead of at targets worth a human’s time. Verizon’s 2026 Data Breach Investigations Report counts fifteen attack techniques already boosted by generative AI, 31% of breaches starting from software vulnerabilities, and 48% involving ransomware.

You have no trillion dollars of architecture to rethink.

📚 So what follows is an audit you run yourself with Claude, where every check is a command you copy and a prompt you paste. No security background required, no tooling beyond two one-line installs, and every prompt is printed in full below, ready to paste as it is.

By the end of the weekend you will know, with evidence you can point a finger at:

  • which ex-employee still has live access, and to what

  • how many people could take over your company today

  • which tool can read every document in your Drive

  • whether a stranger can send an invoice as your domain

  • which live keys are in your history, your repo, your frontend, and your Slack

  • how to rotate them without taking production down

  • whether user A can read user B’s data by changing a number in a URL

  • which vulnerable dependencies production actually touches

  • how long a restore really takes, and how much data you lose

  • what to do in the first fifteen minutes when it happens

Each of those is a section, and every section moves through the same six steps: what Claude needs, what you run, what you paste into Claude, what Claude returns, how you fix it, and how you verify the fix held.


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Inside you will find:

  1. How to Build Claude a Model of Your Attack Surface

  2. Who Still Has Access to Everything You Own?

  3. Can Someone Send an Invoice in Your Name?

  4. Where Your API Keys Are Leaking Right Now

  5. How to Make Claude Review Every Pull Request

  6. How to Verify Your Authorization Boundaries on Staging

  7. Do Your Backups Actually Restore?

  8. The One-Page Runbook for the Day It Happens


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