DIY dev tools: How this engineer created “Flowy” to visualize his plans and accelerate coding
CJ Hess demonstrates how to build custom AI-native developer tools that improve the workflow between engineers and AI models like Claude Code. Rather than relying on existing tools, Hess created Flowy, a visualization tool that converts JSON schemas into interactive flowcharts and UI mockups, enabling more effective planning and communication with AI coding assistants. The episode showcases a practical, modern development workflow where engineers can customize their entire AI engineering environment for individual productivity.
Key takeaways
- • Claude Code excels at intent understanding and steering compared to other models, making it ideal as the foundation for building a personalized ecosystem of developer tools.
- • Environment setup and developer configuration is an underappreciated use case where AI agents can handle tedious chores like resolving linter misalignments and installing dependencies without manual intervention.
- • Building custom dev tools with AI is now economically viable; engineers should prioritize building V1 themselves rather than purchasing expensive SaaS solutions, since the cost of generating code has become negligible.
- • Flowy solves the limitation of ASCII art diagrams by providing a JSON-based format that Claude can read and write natively, allowing visual communication between humans and AI agents through a shared code substrate.
- • Skills act as living documentation for AI agents; they should be iteratively refined based on real usage failures rather than written perfectly upfront, with examples and templates that help models understand custom tools.
- • Using Codex as a secondary reviewer to check Claude's work identifies logical errors, code smells, and architectural improvements without requiring detailed prompts, functioning like a senior engineer code review.
- • The emerging paradigm of AI-native development will likely shift from markdown-based planning to multi-modal interfaces where humans and AI can communicate visually and understand each other's intent more effectively.
Recommendations (5)
"Working with Claude is just such a delight. It just feels so steerable and I think the one thing it really has is intent understanding."
CJ Hess
"I've been on Claude Code, I don't know, maybe last May. It's really enabled me to build a little ecosystem of my own tools around it."
CJ Hess · ▶ 3:32
Mentioned (5)
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