gstack — Garry Tan's Open-Source Software Factory for Claude Code
The exact Claude Code setup YC President Garry Tan uses daily, at 122k stars: 23 specialist roles plus 8 power tools that turn AI into a full engineering team — a CEO who rethinks the product, an eng manager who locks architecture, a designer who catches AI slop, a QA lead driving a real browser, a security officer running OWASP audits, and a release engineer who ships the PR. Free, MIT.
gstack is the complete Claude Code workflow open-sourced by Garry Tan (President & CEO of Y Combinator, early Palantir engineer, Posterous co-founder). The README's own numbers: 3 production services and 40+ features shipped part-time in 60 days, and a self-measured ~810× productivity multiple over the 2013 baseline by logical code change — with a full methodology doc inviting scrutiny.
The core isn't a pile of tools but a process: Think → Plan → Build → Review → Test → Ship → Reflect. Twenty-three specialist skills chain in sprint order — /office-hours reframes your product with six forcing questions and writes a design doc, /plan-ceo-review challenges scope, /plan-eng-review locks architecture and a test matrix, /review catches production bugs, /qa drives a real browser through your flows, /ship runs tests and opens the PR. Each step's output feeds the next.
Coverage is unusually broad: beyond Claude Code it adapts to 10 AI coding agents (Codex, Cursor, OpenCode and more) plus OpenClaw orchestration. Everything is Markdown skills and slash commands — 30-second install, free, MIT.
For technical founders who still ship, Claude Code newcomers who want structured roles instead of a blank prompt, and tech leads who want rigorous review/QA/release on every PR.
FAQ
What is gstack?
An open-source Claude Code workflow by YC President Garry Tan: 23 specialist skills plus 8 power tools covering the full sprint — product definition, architecture review, code review, real-browser QA, and shipping the PR. All Markdown skills and slash commands.
Is gstack free? What license?
Completely free — MIT-licensed open source. Fork it, modify it, use it commercially.
How do I install gstack?
About 30 seconds: git clone into ~/.claude/skills/gstack and run ./setup. Requires Claude Code, Git, and Bun 1.0+. Team mode is one command and gives every collaborator gstack automatically.
Does it only work with Claude Code?
No. Beyond Claude Code it adapts to 10 AI coding agents — Codex CLI, OpenCode, Cursor, Factory and more (via ./setup --host) — plus OpenClaw orchestration.
Which command should I start with?
The official path: start with /office-hours to describe what you are building, then /plan-ceo-review on a feature idea, /review on a branch, and /qa on your staging URL — one loop tells you if it fits.