TypeScript Best Practices for 2025

TypeScript continues to evolve with new features and patterns. Here are the best practices you should follow.

Type Safety First

Always enable strict mode in your tsconfig.json:

{
  "compilerOptions": {
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true
  }
}

Use Type Inference

Let TypeScript infer types when possible:

// Good
const message = "Hello, TypeScript!";

// Avoid
const message: string = "Hello, TypeScript!";

Utility Types

Leverage built-in utility types:

type User = {
  id: string;
  name: string;
  email: string;
};

// Partial - make all properties optional
type PartialUser = Partial<User>;

// Pick - select specific properties
type UserPreview = Pick<User, 'id' | 'name'>;

// Omit - exclude properties
type UserWithoutEmail = Omit<User, 'email'>;

Discriminated Unions

Use discriminated unions for type-safe state management:

type LoadingState = 
  | { status: 'idle' }
  | { status: 'loading' }
  | { status: 'success'; data: any }
  | { status: 'error'; error: Error };

Conclusion

Following these best practices will help you write better TypeScript code that's easier to maintain and refactor.