How to Make Claude Code Your AI Engineering Team

GStack is an open-source toolkit built by YC President & CEO Garry Tan that turns Claude Code into an AI engineering team — with skills for office hours, design, code review, QA, and browser testing. Use it with Claude Code or Codex or Cursor. It's free and open source: https://github.com/garrytan/gstack In this video, Garry walks through how GStack works, starting with Office Hours, a skill modeled after real YC partner sessions that pressure-tests your idea before you write a line of code. He demos it live, going from idea through adversarial review, design mockups, and automated QA in a single session. 00:00 – AI Just Changed Coding Forever 00:09 – From YC to Building With AI 01:07 – Why AI Coding Feels So Different 02:45 – Turning AI Into a Real Team (GStack) 03:45 – Let’s Build an App Live 05:23 – The Question That Kills Most Ideas 07:13 – This Idea Just Got Way Bigger 08:38 – The “Feels Illegal” AI Hack 10:50 – Upgrading the Idea in Real Time 12:44 – Breaking + Fixing the Plan 14:25 – AI Designs the App 16:59 – The Full System Explained 18:00 – Running Multiple AI Engineers 20:00 – Shipping 10x Faster 21:20 – The Only Thing That Matters Now Apply to Y Combinator: https://www.ycombinator.com/apply Work at a startup: https://www.ycombinator.com/jobs https://www.conductor.build/

Garry Tanhost

Apr 23, 202621mWatch on YouTube ↗

EPISODE INFO

Released: April 23, 2026
Duration: 21m
Channel: Y Combinator
Watch on YouTube: ▶ Open ↗

EPISODE DESCRIPTION

GStack is an open-source toolkit built by YC President & CEO Garry Tan that turns Claude Code into an AI engineering team — with skills for office hours, design, code review, QA, and browser testing. Use it with Claude Code or Codex or Cursor. It's free and open source: https://github.com/garrytan/gstack In this video, Garry walks through how GStack works, starting with Office Hours, a skill modeled after real YC partner sessions that pressure-tests your idea before you write a line of code. He demos it live, going from idea through adversarial review, design mockups, and automated QA in a single session. 00:00 – AI Just Changed Coding Forever 00:09 – From YC to Building With AI 01:07 – Why AI Coding Feels So Different 02:45 – Turning AI Into a Real Team (GStack) 03:45 – Let’s Build an App Live 05:23 – The Question That Kills Most Ideas 07:13 – This Idea Just Got Way Bigger 08:38 – The “Feels Illegal” AI Hack 10:50 – Upgrading the Idea in Real Time 12:44 – Breaking + Fixing the Plan 14:25 – AI Designs the App 16:59 – The Full System Explained 18:00 – Running Multiple AI Engineers 20:00 – Shipping 10x Faster 21:20 – The Only Thing That Matters Now Apply to Y Combinator: https://www.ycombinator.com/apply Work at a startup: https://www.ycombinator.com/jobs https://www.conductor.build/

SPEAKERS

Garry Tan
host
President and CEO of Y Combinator, former early Palantir employee and co-founder of Posterous.

EPISODE SUMMARY

In this episode of Y Combinator, featuring Garry Tan, How to Make Claude Code Your AI Engineering Team explores garry Tan shows GStack turning Claude Code into engineering teams GStack is presented as a “thin harness, fat skills” framework that adds process, roles, and reviews so coding agents stop wandering and producing plausibly wrong code.

RELATED EPISODES