tl-backend-style-guide

Apply backend TypeScript conventions when generating, editing, or reviewing server-side code. Use when writing services, repositories, route handlers, domain models, error classes, or any non-React TypeScript. Covers module structure, class patterns, file naming, error handling, data access, and code style. This is a foundational skill - use it alongside more specific skills (e.g. database, Fastify) when those apply.