A Application Development developer specializes in designing, building, and maintaining enterprise-level applications using Java Platform, Enterprise Edition (). This involves creating scalable, large-scale systems and ensuring their stability, reliability, and performance. They design and implement application components and interfaces, code in Java, and use frameworks like Spring and Hibernate. They collaborate with other teams to integrate applications and troubleshoot any issues. They also refine and optimize application performance, and ensure data security and integrity. They may be involved in all stages of the development lifecycle, from initial concept and design to testing and deployment.