Writing asynchronous code in Node.js is essential for building scalable and responsive applications. However, poorly structured asynchronous logic can lead to hard-to-maintain code and subtle bugs. To help you write robust and maintainable asynchronous code, keep the following best practices in mind:

• Always handle errors: never ignore errors in callbacks, Promises, or async functions. Use try/catch with async/await, .catch() with Promises, and always check the error argument in callbacks;
• Avoid deeply nested callbacks: this pattern, known as "callback hell", makes code difficult to read and debug. Use named functions, modularize logic, or refactor to Promises and async/await;
• Prefer Promises and async/await: these modern patterns are easier to read and maintain than callbacks. They make asynchronous flows look more like synchronous code, improving clarity;
• Keep async flows readable: break up complex logic into smaller functions, use descriptive names, and avoid mixing many different asynchronous styles in the same codebase.