An ACE/TAO developer works with the Adaptive Communication Environment (ACE) and The ACE ORB (TAO), which are open-source frameworks used for building high-performance networked applications. They develop, maintain, and optimize systems using these frameworks to ensure efficient communication and data exchange. Their tasks include writing code, debugging, and testing to meet specific client needs. They also work on improving system performance, scalability, and real-time communication. Additionally, these developers often collaborate with other software engineers to design robust, reliable, and flexible applications, while also troubleshooting any software issues that may arise.