YC President Garry Tan’s Open-Source Project Gains Traction
Recently, the open-source project “gstack,” created by Y Combinator President and renowned Silicon Valley investor Garry Tan, has garnered significant attention within the developer community. Launched in March 2024, the project amassed over 20,000 stars on GitHub in just six days. gstack is an AI programming workflow specifically designed for the large language model Claude Code, aiming to enhance the professionalism and efficiency of AI-assisted software development.
Core Concept: From a Single AI to a Specialized Agent Team
Traditionally, developers issue commands directly to an AI model, which then completes all tasks—from product planning to code implementation—in a generalist fashion. The results are often functional but lack depth and specialization. The core idea behind gstack is to break away from this “one-size-fits-all” model and instead adopt a multi-agent collaborative approach.
The workflow’s philosophy is to break down the software development process, assigning an AI agent with a specific “persona” and professional skills to each stage. Garry Tan believes that different tasks, such as product planning, code review, and engineering rigor, require distinct mindsets, and handling them all together leads to mediocre results. By setting clear role divisions for the AI, gstack simulates a professional software development team where tasks are clearly defined and each member has specific responsibilities.
Structural Design: 12 “Skills” Covering the Full Lifecycle

gstack comes with 12 core “Skills,” each corresponding to a key role in a software development team, for example:
- CEO: Responsible for strategic review and stress-testing the product direction.
- Tech Lead: Reviews and finalizes the technical implementation plan.
- Senior Designer: Evaluates and guides the product’s visual design and user experience.
- Staff Engineer: Conducts code quality reviews with extremely rigorous standards.
- Release Engineer: Manages automated deployment and release processes.
Together, these roles cover the entire software development lifecycle, from initial requirement ideation, product planning, and technology selection to coding, review, testing, deployment, and even post-project retrospectives. Users can invoke the corresponding AI role at different stages of development with simple commands, ensuring that each step is handled professionally.
Technical Implementation: Optimizing Token Efficiency via CLI
gstack’s technical implementation demonstrates a deep consideration for AI interaction efficiency. Take its /design-review skill, for example, which requires the AI to analyze the visual experience of a specified website. Traditional browser automation often uses methods like the Multi-Component Protocol (MCP), where each interaction requires transmitting a protocol frame containing the full JSON Schema. This leads to massive token consumption, especially in multi-step operations, where the protocol overhead far exceeds the useful information.
To solve this problem, gstack compiles the browser automation logic into a standalone Command-Line Interface (CLI) binary. The AI (like Claude Code) can then interact with this binary by executing simple command-line instructions through its native Bash tool, with inputs as arguments and outputs as plain text. This approach drastically reduces the token overhead during interaction, making the execution of complex tasks more cost-effective and feasible.
Application Workflow and Future Potential
gstack’s application model is a clear pipeline. A developer first describes the requirements, then sequentially calls /plan-ceo-review and /plan-eng-review for planning, followed by the coding phase. Upon completion, /review can be used for code review, /qa for testing, and finally, /ship to complete the deployment. After the project cycle, /retro can be used for a retrospective summary.
This workflow not only provides a fixed toolset but is also designed to be continuously optimized through ongoing use. By breaking down the complex software engineering process into a series of specialized, collaborative AI tasks, gstack offers an effective way for individual developers and small teams to simulate the working model of a large, mature development team.