TypeScript Best Practices for 2023

TypeScript has become the de facto standard for large-scale JavaScript applications. Here are some best practices to follow in 2023.

Strict Mode

Always enable strict mode in your tsconfig.json:

{
  "compilerOptions": {
    "strict": true
  }
}

This enables:

• Strict type checking
• No implicit any
• Strict null checks

Type Inference

Let TypeScript infer types whenever possible:

// Bad
const count: number = 0;

// Good
const count = 0;

Interfaces vs Types

Prefer interfaces for object shapes:

interface User {
  name: string;
  age: number;
}

Use types for unions, tuples, or complex types:

type Status = 'active' | 'inactive' | 'pending';

Utility Types

Leverage built-in utility types:

// Make all properties optional
Partial<User>

// Make all properties readonly
Readonly<User>

// Pick specific properties
Pick<User, 'name'>

Error Handling

Use custom error types for better debugging:

class ApiError extends Error {
  constructor(public status: number, message: string) {
    super(message);
  }
}

Adopting these practices will make your TypeScript code more maintainable and less prone to errors.