Spec-Driven Development with AI: How I Built a Production Multi-Agent System Without Writing a Line…

📰 Medium · DevOps

Learn how to build a production-ready multi-agent system using spec-driven development with AI, without writing a line of code first.

advanced Published 20 Apr 2026

Action Steps

Define the system specifications using a clear and concise language
Use a tool like LangGraph to generate the system architecture
Implement the system using FastAPI and AWS
Test and validate the system against the specifications
Refine and iterate on the system based on the test results

Who Needs to Know This

Developers and DevOps teams can benefit from this approach to build complex systems efficiently, and product managers can use this to streamline the development process.

Key Insight

💡 Spec-driven development with AI can help build complex systems efficiently and accurately, without the need for manual coding.

Key Takeaways

Learn how to build a production-ready multi-agent system using spec-driven development with AI, without writing a line of code first.

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Title: Spec-Driven Development with AI: How I Built a Production Multi-Agent System Without Writing a Line…

URL Source: https://medium.com/@leecheekeong/spec-driven-development-with-ai-how-i-built-a-production-multi-agent-system-without-writing-a-line-27bfaf4cea22?source=rss------devops-5

Published Time: 2026-04-20T19:53:26Z

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# Spec-Driven Development with AI: How I Built a Production Multi-Agent System Without Writing a Line of Code First | by Lee Chee Keong | Apr, 2026 | Medium

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# Spec-Driven Development with AI: How I Built a Production Multi-Agent System Without Writing a Line of Code First

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A walkthrough of Sentinel MAS — a real LangGraph + FastAPI + AWS system built phase-by-phase using specs as the source of truth, not prompts.

**Estimated read time**: 10 min Tags: Artificial Intelligence, Software Development, AWS, Python, LLM

## The Problem With “Vibe Coding”

When you ask an AI to “build me a multi-agent system,” you get something fast. You also get something fragi

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Spec-Driven Development with AI: How I Built a Production Multi-Agent System Without Writing a Line…

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