An API Portal Developer designs, builds, and maintains API portals, which are interfaces for interacting with APIs. They handle the development of user interfaces, ensuring that they are user-friendly and efficient. They also manage API documentation, creating clear guides and references for users. Additionally, they work on API testing, debugging, and problem-solving to ensure optimal performance. They may also design and implement API security measures. Their work involves collaboration with other software developers, UI/UX designers, and possibly clients, to deliver a functional, efficient, and secure platform for API interaction.