Design Patterns in TypeScript

Apply these patterns when designing or refactoring TypeScript code.

PATTERN CATALOGS

Full per-pattern catalogs (intent, TypeScript code example, use-when notes) live in references/. Read the file for the category you need:

• Creational (Factory Method, Abstract Factory, Builder, Singleton, Prototype) — see references/creational.md
• Structural (Adapter, Decorator, Facade, Proxy, Composite, Bridge, Flyweight) — see references/structural.md
• Behavioral (Strategy, Observer, Command, State, Chain of Responsibility, Iterator, Template Method, Mediator, Memento, Visitor) — see references/behavioral.md

CHOOSING THE IDIOMATIC FORM

Before reaching for a class-heavy GoF implementation, prefer the simplest TypeScript construct that expresses the pattern: