TypeScript Guidelines

Standards and best practices for TypeScript development with modern tooling. Follow these guidelines when writing or modifying TypeScript code.

Design Principles

Apply DRY, KISS, and SOLID consistently. Prefer functional approaches where relevant; use classes for stateful behavior. Use composition over inheritance. Each module should have a single responsibility. Use dependency injection for class dependencies.

Code Style

• Naming: Descriptive yet concise names for variables, functions, and classes
• Documentation: JSDoc comments for public APIs, complex logic, and non-obvious design decisions
• Type annotations: Be explicit with typing to reduce inference time; avoid any unless necessary
• Imports: Avoid barrel exports to prevent circular dependencies; prefer direct imports

Type Safety

• Strict TypeScript: Use strict mode with proper type definitions. Use type-safe patterns like Zod schemas for validation and type-safe DOM helpers where applicable.
• Avoid any: Use unknown instead of any when the type is truly unknown. Narrow types appropriately.