Hiring a JAX-RS developer brings expertise in creating web services following the REST architectural pattern in Java environment. They can help in developing lightweight, scalable, and easy-to-maintain applications. With their knowledge in building RESTful APIs, they can ensure smooth communication between your application and other systems. They are also adept at handling JSON, XML responses, and HTTP methods, crucial for efficient data exchange. Their understanding of JAX-RS, a part of Java EE technologies, guarantees robust and secure applications. Therefore, hiring a JAX-RS developer can significantly streamline your web services development process.