Hiring a Jax-RS developer ensures you have an expert in building Java-based web services according to the REST architectural pattern. They can efficiently create scalable, maintainable, and secure APIs for your applications. Their proficiency in handling HTTP methods, URI mapping, and response entities ensures effective communication between web services. They are also skilled in integrating these services with other applications. Their knowledge of Jax-RS helps in seamless data exchange in various formats, improving cross-platform compatibility. Overall, they can significantly contribute to your application's interoperability and functionality.