TypeScript Best Practices for 2025

# TypeScript Best Practices for 2025 TypeScript has become the de facto standard for building robust JavaScript applications. In this guide, we'll explore the best practices that will help you write cleaner, more maintainable TypeScript code. ## 1. Use Strict Mode Always enable strict mode in your `tsconfig.json`: ```json { "compilerOptions": { "strict": true, "noImplicitAny": true, "strictNullChecks": true } } ``` ## 2. Leverage Type Inference TypeScript's type inference is powerful. Let it work for you: ```typescript // ❌ Redundant const name: string = "John"; // ✅ Better const name = "John"; ``` ## 3. Use Union Types Wisely Union types are one of TypeScript's most powerful features: ```typescript type Status = "pending" | "success" | "error"; function handleStatus(status: Status) { switch (status) { case "pending": return "Loading..."; case "success": return "Done!"; case "error": return "Failed!"; } } ``` ## 4. Avoid `any` Type The `any` type defeats the purpose of TypeScript. Use `unknown` instead: ```typescript // ❌ Avoid function processData(data: any) { return data.value; } // ✅ Better function processData(data: unknown) { if (typeof data === "object" && data !== null && "value" in data) { return (data as { value: string }).value; } } ``` ## 5. Use Utility Types TypeScript provides powerful utility types: ```typescript interface User { id: string; name: string; email: string; password: string; } // Pick only what you need type PublicUser = Omit ; // Make everything optional type PartialUser = Partial ; // Make everything required type RequiredUser = Required >; ``` ## Conclusion Following these TypeScript best practices will help you build more robust and maintainable applications. Remember, TypeScript is there to help you catch errors early and improve your development experience. Happy coding!