A YC CEO’s open-source software factory for Claude Code

What it does

gstack is a set of 23 opinionated slash-command skills—/office-hours, /review, /qa, /ship, and others—that turn Claude Code into a virtual engineering org. Each command adopts a persona—CEO, eng manager, designer, QA lead, security officer—and runs a specific phase of a product sprint, from reframing the problem to opening a real browser for end-to-end testing. The skills chain together automatically: a design doc written by /office-hours feeds into /plan-ceo-review, whose output feeds into /plan-eng-review, and so on until /ship opens the pull request. It is, in essence, a management methodology expressed as Markdown prompts and shell glue.

The interesting bit

The project treats prompt engineering as organizational design. Tan claims his 2026 run rate is roughly 810× his 2013 pace—11,417 versus 14 logical code changes per day—measured across 40 repos, and he publishes the full methodology and caveats openly. The stack also auto-detects and installs into ten different AI agents, from OpenAI Codex to Cursor, though Claude Code is clearly the first-class citizen.

Key highlights

• 23 specialist roles mapped to slash commands (/cso for security audits, /qa for real browser testing, /retro for weekly reflection)
• Skills chain sequentially: downstream commands automatically read artifacts produced by upstream ones
• Supports ten AI coding agents via host-specific installation, though Claude Code is the first-class citizen
• Team mode silently auto-updates skills for shared repositories without vendoring files
• Includes native OpenClaw skills for conversational planning and debugging without spawning a full coding session

Caveats

• The dramatic productivity metrics are self-reported and normalized by the author; the README includes a dedicated caveat page about LOC inflation
• It is fundamentally a prompt-and-process wrapper around Claude Code; if you do not use a supported agent, there is no standalone tool
• The workflow is aggressively opinionated—it will “push back on your framing”—so it assumes you want to be challenged, not just assisted

Verdict

Try it if you are a technical founder or staff engineer who already lives in Claude Code and wants a structured, opinionated workflow to force-multiply shipping. Skip it if you are looking for a generic IDE plugin or a coordination tool for human teams.