typescript-service-patterns

What problem does it solve?

Solve the problem of writing robust, testable business logic in TypeScript by replacing exceptions with explicit Result types.

Core Features & Use Cases

• Result type pattern for explicit success/failure without throwing exceptions across service boundaries.
• Typed error definitions (unions and structured errors) to improve compile-time safety and runtime clarity.
• Layered service architecture with a pure service layer, repository pattern, and DI-friendly design, enabling framework-agnostic usage in Next.js, Node.js, or any TS project.
• Repository pattern examples including Firestore-like implementations and mock repos for deterministic unit tests.

Quick Start

Create a small TypeScript service using Result types and a repository, and write a test that asserts correct error handling.