TypeScript Best Practices for Production Applications

TypeScript has become the standard for serious JavaScript projects. Here are practical tips for making your TypeScript codebase robust and maintainable.

Strict Mode: Always enable "strict": true in tsconfig.json. This enables all strict type-checking options and catches more errors at compile time.

Discriminated Unions: Use discriminated unions for complex state management instead of optional properties:

type State = | { status: 'loading' } | { status: 'success'; data: Data } | { status: 'error'; error: Error };

Utility Types: Master Partial<T>, Required<T>, Pick<T>, Omit<T>, Record<K,V> to write concise, maintainable types.

Avoid any: Use unknown when you truly don’t know the type, and narrow it with type guards. any defeats the purpose of TypeScript.

Brand Types: Create branded types for primitive values that need semantic meaning:

type UserId = string & { __brand: 'UserId' };
type OrderId = string & { __brand: 'OrderId' };

These patterns have saved countless hours debugging production issues.