TypeScript Best Practices for Large-Scale Applications

TypeScript shines brightest in large codebases where type safety prevents entire categories of bugs. But scaling TypeScript requires intentional practices and patterns.

Strict Mode Always

Enable strict mode from day one. The additional type checking catches subtle bugs early and forces you to think carefully about your data structures.

Discriminated Unions

Use discriminated unions to model state that can take different forms. TypeScript's exhaustiveness checking ensures you handle every case.

Utility Types

Leverage TypeScript's built-in utility types like Partial, Pick, and Omit to derive new types from existing ones. This reduces duplication and keeps your type definitions DRY.

Branded Types

Use branded types to distinguish between values that share the same underlying type but represent different concepts, like UserId vs. ProductId.