A customer interface developer designs and implements the part of software that users directly interact with. They focus on creating user-friendly, intuitive, and engaging interfaces that enhance user experience. They understand customer needs, translate them into technical requirements, and use programming languages like HTML, CSS, JavaScript for web development. They also test interfaces, troubleshoot issues, and optimize performance. Furthermore, they often collaborate with UX/UI designers and back-end developers to ensure seamless functionality and aesthetic appeal. Their ultimate goal is to create interfaces that facilitate easy and effective interaction between the user and the software.