Hiring a Handlebar.js developer is beneficial for dynamic web application development. They can create efficient, reusable UI components, reducing development time. Handlebar.js enables developers to separate the generation of HTML from the rest of JavaScript, enhancing maintainability. It also supports precompilation, improving loading times and performance. Their knowledge can also help in managing data binding and updates, ensuring the application remains responsive and user-friendly. With a Handlebar.js developer on board, your project can achieve a streamlined, efficient, and high-performing web application.