kamae-ts — Functional Domain Modeling

A reading version of the principles to follow when modeling domains in server-side TypeScript. Instead of class-based OOP, we lean on the TypeScript type system and a functional approach.

This is a human-oriented reorganization of the knowledge base used by the coding-agent skills shipped in the kamae-ts plugin.

💬 Join the Discord community

A Discord server for discussion, questions, and casual chat about server-side TypeScript and functional domain modeling. You do not need to be a heavy kamae-ts user — newcomers welcome.

→ Join the Discord

See the Community page for details.

Start reading

Each chapter is reachable from the left sidebar, or from the links below.

• Type-Driven Domain Modeling
• State Transitions via Pure Functions
• Error Handling — Railway Oriented Programming
• Boundary Defense
• Declarative Style
• Test Data
• Code Review

Applying the principles

These are recommendations, not strict rules. Use judgment based on context, but when you depart from a principle, document the reason in a comment.

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Table of contents

• Installation
• Community
• Type-Driven Domain Modeling
• State Transitions via Pure Functions
• Error Handling
• Boundary Defense
• Declarative Style
• Test Data
• Code Review