TypeScript Best Practices for Modern Web Development

TypeScript has revolutionized how we write JavaScript, providing type safety and better developer experience. Here are some essential practices I’ve learned from years of TypeScript development.

Type Definitions

Use Interface for Object Shapes

interface User {
  id: string;
  name: string;
  email: string;
  createdAt: Date;
}

Use Type for Unions and Computed Types

type Theme = 'light' | 'dark' | 'auto';
type UserWithoutId = Omit<User, 'id'>;

Utility Types

TypeScript’s built-in utility types are incredibly powerful:

• Partial<T> - Makes all properties optional
• Required<T> - Makes all properties required
• Pick<T, K> - Selects specific properties
• Omit<T, K> - Excludes specific properties

Generic Constraints

Use generic constraints to make your functions more flexible while maintaining type safety:

function getProperty<T, K extends keyof T>(obj: T, key: K): T[K] {
  return obj[key];
}

Strict Configuration

Always use strict mode in your tsconfig.json:

{
  "compilerOptions": {
    "strict": true,
    "noUncheckedIndexedAccess": true,
    "exactOptionalPropertyTypes": true
  }
}

These settings catch many common errors at compile time rather than runtime.