functional-ts

What problem does it solve?

Domain modeling in server-side TypeScript often becomes brittle when using classes; this Skill provides a functional approach using discriminated unions, pure functions, and Result types to ensure safer, more maintainable domain logic.

Core Features & Use Cases

• Discriminated unions for state modeling with kind as discriminant.
• Pure state transitions as deterministic functions.
• Error handling with Result types and exhaustive error typing.
• Validation boundary integration and PII protection with Sensitive type.
• Use cases include modeling workflows like taxi dispatch, order processing, and API boundaries.

Quick Start

Create a simple domain with Waiting and EnRoute states and demonstrate a pure transition from Waiting to EnRoute when a driver is assigned.